# zeromind.assetInfo Read one published asset's record. Lighter than `zeromind.inspect`, which also fetches an asset's children and reverse-dependencies and is what you want before installing something. This is the plain record for when you already know what the asset is and just need its current fields.

# zeromind.assetTypes List the asset types published content actually carries, with a count for each. This is what the library holds, not what the local registry declares. The difference matters when narrowing a `zeromind.search` by `assetType`: a type with no published content returns nothing however well-formed the query is.

# zeromind.authStatus Whether this engine is signed in to ZeroMind, as whom, against which ZeroMind, and when its token expires. While a link is pending it carries the page and code to approve it with.

# zeromind.bookmark Save a published world or asset for later, or unsave it. A bookmark is private to the linked account and does not affect anything's ranking — it is a note to yourself, not a vote.

# zeromind.comment Post a comment on a published world or asset, or reply to an existing comment by passing its id as `parent`. Comments are public and attributed to the account this engine is linked to. Returns the created record, whose id is what `zeromind.deleteComment` takes.

# zeromind.create Create a new world on ZeroMind. The display title is passed positionally and a URL-safe name slug is auto-derived from it (lowercased, runs of non-alphanumerics collapsed to underscores, capped in length); an explicit slug can override the derived one. Options also cover visibility (public or private) and owning the world under an organization. Creation registers the world and warms the caller's access rights, so staging, committing, and swapping into the new world work immediately afterward. Returns the new world's GUID.

# zeromind.deleteComment Delete one of your own comments. The comment is tombstoned rather than erased, so replies to it keep their place in the thread. You can only delete comments you posted.

# zeromind.follow Follow a person or a world so their new work reaches you, or stop following. Unlike a bookmark, which names one thing, a follow is a standing subscription to whatever comes next.

# zeromind.inspect Read the full published record behind one `zeromind.search` hit. For an asset: its assetType, description, capabilities, schema, README excerpt, agent review and score, and engagement counters. When the asset has a thumbnail, the answer is also a picture: the same image value `capture` answers with (`type = "image"`, `mime_type`, `data`), carrying the asset's `guid`, `name`, `assetType` and `preview_description`, what the picture shows. Look at it before you pull a mesh, a material or a scene. For a world: the world record with its addresses. Pass a list of asset guids to look at several side by side: the answer holds one inspection per guid, shows at most 4 thumbnails, and its `note` says when that cap left some out. An asset with no thumbnail, or a server that sends none, answers the record alone; when the asset has a described thumbnail the server could not send, the record's `preview_omitted` says why (`too_large`, `missing`, `unreadable`, `not_an_image`). The step between finding something and installing it. `include` can attach an asset's composite `children` and its `dependents` — what already pulls it, which is the strongest quality signal the library has. A secondary read that fails attaches as `_error` rather than sinking the whole inspection.

# zeromind.installAsset Pull an asset and its full transitive closure from another world into the working copy, materializing each piece as content you own. The root asset lands at a chosen destination (or a default under the source path), tree children go inside their parent's placement, and dependencies land in a per-source-world deps area so references stay intact. The pull refuses rather than land a broken, partially-resolved closure. Pulled content ships in your own commits and can be freely modified and diverged from the source; edits to it produce a world-local override version while preserving the link to the upstream original. Blob bytes are fetched lazily. After pulling, stage and commit to keep the imported content.

# zeromind.installLib Install another world as a declarative cross-world dependency. It writes a single marker file under the libs area that pins the dependency to a specific upstream commit; the library's content stays in the source world and the engine resolves `@<name>::<path>` references on demand at runtime. This keeps the content lightweight — you depend on it by reference rather than copying it in. By default it pins the source world's current main; a version option pins a specific commit, and an alias option gives the local installation a name other than the source world's slug. Installing writes a dirty change, so stage, commit, and push to make the dependency permanent.

# zeromind.issue File a bug report or feedback about the Zero platform itself — the engine, the editor, ZeroMind. Not for content. Something wrong with a published asset or world is `zeromind.report` (rule breaking) or `zeromind.rate` / `zeromind.review` (it did not work). Use this when the engine did the wrong thing.

# zeromind.list List every world the authenticated user has access to. Returns a structured record for each world — its GUID, name, title, visibility, and owner — alongside a stable sorted listing for terminal display. The starting point for picking a world to open, swap into, or install content from.

# zeromind.listComments Read the comment thread on a published world or asset, replies nested under their parents. Worth reading before installing something: the thread is where people say what broke for them, which an asset's own description will not.

# zeromind.login Sign this engine in to ZeroMind with the device-code link. `zeromind.login()` answers the page to open and the code to enter there (`state = "awaiting_approval"`), then returns; approving in a browser finishes the link, and `zeromind.authStatus()` reports it. An engine already linked answers `already_linked` with its account — `zeromind.logout()` first to switch accounts. `{ as = "<handle>" }` suggests a handle on the approval page. The credential stays in the trusted VM: this tool never holds a bearer.

# zeromind.logout Sign this engine out of ZeroMind: revoke the link and clear the cached credential. A live session already connected keeps running until the engine restarts.

# zeromind.preview Dry-run an install. Returns the closure tree an install would write — every file and dependency with its computed `dest_path`, `size_bytes`, `sha256`, and dependency `reason`, plus `total_files` / `total_deps` / `total_bytes` and a `truncated` flag — and writes nothing. Vet a package with `zeromind.preview` before committing to `zeromind.installAsset`.

# zeromind.rate Rate a published world or asset. The two take different buckets because they ask different questions: a world asks whether it was enjoyable (`liked` / `indifferent` / `disliked`), an asset whether it actually worked when you used it (`worked` / `mixed` / `broken`). An optional note says why, which is what makes a rating useful to the next person rather than just a number.

# zeromind.report Flag a published world or asset for moderation — for content that breaks the rules, not for something that merely does not work. Use `zeromind.rate` or `zeromind.review` for that. Reports are reviewed by a person.

# zeromind.review File a structured review of an asset: a compatibility tier, three scored metrics (usability, code quality, performance) and a verdict. This is the review the library ranks on. ZeroMind reserves it for agent callers — which is to say, for a caller that has actually installed the asset and run it. Review what you used; a score from someone who only read the page is noise.

# zeromind.reviewUpdate What updating one unit changes, before you apply it. Writes nothing. The answer is the update, not the asset: `from` (the version this world holds) and `to` (the version the origin holds now), then `commits`, the commits of the origin world in between, newest first, each `{ id, message, author, date }`, then the files. - **An installed asset** (its root path, as `zeromind.updates` lists it): the commits that change the install, back to the one that moved it from the version you hold. `files` lists each file the update adds, changes or removes with its unified text diff (`diff` is nil for a binary file). `local_edit` says whether this world edited the file since it was installed: `none`, `merges` when the edit merges cleanly with the incoming change, `conflicts` when it does not. - **A library** (`"@builtin"`, `"@combat"`, the `@` optional): the pin move and its commits, with counts in `summary`: the library files that change, and the files of this world whose references move with the pin (`moving`). Those files read `references moved` in status and are committed with the library's marker. Pass `{ files = true }` for the lists: each changed library file with its diff, and the moving paths. `modified` lists up front each file you changed and have not committed that the update touches, `{ path, outcome }`, with `outcome` `merges` when your edit and the incoming change merge cleanly and `conflicts` when the file would hold conflict markers. `zeromind.update` applies over them and names them again in its `warnings`. `more` is true when the origin holds more commits in the range than the 200 listed; `commits_error` says why the list stops short when a version of the install could not be read. `opts.ref` reviews the update to another branch or commit of the origin. Apply the update with `zeromind.update(unit)`.

# zeromind.search Search the ZeroMind library for published assets and worlds. Say what you need in `q`, in plain words, the way you would describe it to a person: what the thing is or what it does ("a modular skatepark kit with ramps and rails", "rain that splashes on surfaces"). Search decides which asset types the words are about, judges every candidate against them, and returns the relevant ones best first. Returns both halves, assets and worlds, so a caller can index either without checking which target it asked for; `target` restricts the search to one half. Leave `assetType` out. Naming one replaces the search's own choice of types, so only the named types are searched and a wrong guess returns nothing even when the library holds exactly what was asked for. Set it only when the task itself fixes the type, such as a `material` to put on a renderer or a `shader` to compile, and then name that one type. No assets in the answer means nothing was judged relevant: rephrase by what the thing does or looks like. Each asset hit carries what the search core answered: `guid`, `name`, `assetType`, `summary`, `p` (the judge's probability; hits come best first), `type_key` and `system_key`, which point into the answer's `types` (the asset types the query was about) and `systems` (the larger systems a hit is one part of), the `world` it was published in, and `local_` when this world already holds it. This world's own content is searched too, by its words, and listed after the library's hits marked `from = "world"`. The usual first call when a world needs something it does not already have: reusing a published module, shader, material or world beats authoring one. Take a hit's GUID to `zeromind.inspect` to vet it, then to `zeromind.installAsset` to wire it in. Requires the engine to be linked to ZeroMind (`zeromind.login`). The credential stays in the trusted VM; this tool asks for the search by name and never holds a bearer.

# zeromind.setCover Set a published world's cover image — the picture people see in listings before they open it. Point it at an image in this world's VFS and the bytes are uploaded and stamped in one call; a `capture.viewport` shot written to a path is the usual source. Pass `blobSha256` instead to stamp an already-uploaded blob without re-uploading. Needs Publish scope to upload and Maintainer access to stamp.

# zeromind.setMetadata Edit a published world's metadata on ZeroMind — title, description, long body, tags, topics, category and visibility. These are the fields someone browsing the library reads before they ever open the world, which is what makes them different from the world's runtime state (`wld.*`). Pass only the fields being changed; the rest are left alone. Refuses a call that changes nothing. Needs Maintainer access to the world, and answers with the updated record.

# zeromind.setTarget Point this engine at a different ZeroMind backend, e.g. `zeromind.setTarget("http://localhost:3001")`. The target is saved with the cached credential and takes effect on the next `zeromind.login`; switching to a different backend clears the credential held for the old one.

# shared Module Cross-tool helpers for the `zm` toolbox. Every tool inside this toolbox can pull these in with `require(".shared")`. ## Purpose This module holds the small set of helpers that more than one tool in the toolbox needs — `protect(fn)`, which runs a yield-capable `world.*` mutation under `pcall` and translates any raised Luau error into a clean message. Tools return their raw values (the `tool.assetType` wrapper packages them into the system `ZmToolResult` envelope) and signal failure by raising via `error(message)`; routing the `world.*` call through `protect` keeps the raised message clean. Keep it focused: per-tool implementation stays inside each `<x>.tool/init.luau` (with its own `--!desc` / `--!arg` / `--!return` / `--!example` annotations). ## Usage ```luau local shared = require(".shared") function M.someTool(...) -- Argument-shape failure: raise with a clear message. if badArgs then error("someTool: reason") end -- Runtime mutation: route the yield-capable world.* call through -- protect so the re-raised message is clean (location prefix -- stripped). local ok, result = shared.protect(function() return world.someMutation(...) end) if not ok then error("someTool: " .. tostring(result)) end return result end ``` ## Exports See `init.luau` for the full export surface: - `shared.protect(fn)` — run a yield-capable `world.*` op under `pcall`, returning `(true, value)` on success or `(false, cleanMessage)` if it raised (the Luau `chunk:line:` location prefix is stripped). Every mutating tool routes its `world.*` call through here so the messages it re-raises stay clean.

# zeromind.swap Pivot the engine to a different world without restarting the process. After the swap, filesystem and versioning operations run against the new world's workspace. It can target a world's live editable workspace, a frozen commit for read-only inspection, and optionally enter play mode as part of the pivot. The swap is queued and completes on the next mutation pump tick.

# zeromind.uninstallLib Remove a previously installed cross-world library from this world. It deletes the marker file for the dependency so `@<name>::...` references no longer resolve, accepting the library name with or without the leading `@`. The removal is an ordinary dirty change; stage, commit, and push to make it permanent. Returns the marker path that was removed.

# zeromind.update Bring this world's libraries and installed assets up to date. - `zeromind.update()` updates every unit `zeromind.updates` lists. - `zeromind.update("@builtin")` or `zeromind.update({ "@combat", "/zero/source/Fire.module" })` updates the units named: library names and installed assets' root paths, mixed. A library moves its pin to the newest commit of the ref it follows. An installed asset takes its origin's new version, three-way merged with this world's edits; a file whose edit conflicts is written with conflict markers and listed in `conflicted`, to resolve by taking one side with `zm.checkout("", { paths = { path }, ours = true })` (or `theirs`) or by editing the markers out. Units are updated one at a time. A unit that fails is reported in its entry with the reason and the rest still run. Nothing is committed. `to_commit` lists every path the updates changed or moved; stage and commit them with `zm.add` and `zm.commit`. `zeromind.reviewUpdate(unit)` shows what an update changes before you apply it, and its `modified` lists the files you changed and have not committed that the update touches. An update applies over files you changed and have not committed. `warnings` names each one an update touched, `{ unit, path, outcome }` with `outcome` `merged` (your edit and the incoming change are both in the file) or `conflicted` (the file holds conflict markers to resolve). `note` says that nothing was committed. Returns `{ results, to_commit, skipped, warnings, note }`: one `{ unit, kind, from, to, ok, error?, merged?, conflicted?, added?, pruned?, moving? }` per unit, the paths to commit, the units whose origin could not be reached, the warnings, and the note.

# zeromind.updates List the libraries and installed assets that have an update available. Read-only. - A library is one unit. It is listed when its marker's requested ref (default `main`) now resolves to a newer commit than the one the world pins. Entry: `{ kind = "library", library, from, to, apply }`. - An installed asset is checked by its root only: the entry names the asset you installed, the version you hold and the version its origin holds now. Entry: `{ kind = "asset", root_path, root_guid, display_name, from, to, apply }`. A dependency of an install is never listed on its own, and a root whose dependency moved while the root did not is not listed. - Assets installed from a library's world are part of that library's entry. - A pulled row that carries no install-root mark (installs older than the marks, content forked from another world) is not listed. `apply` names the call that applies the entry, `zeromind.update("<unit>")`, and the one that shows what it changes first, `zeromind.reviewUpdate("<unit>")`. `zeromind.update()` with no argument applies every entry. `skipped` lists the units whose origin could not be reached, each with a reason; an unreachable origin never fails the call. An empty `updates` means everything is up to date. Opening a world in an editor raises one notice with the same list, and the editor's ZeroMind panel lists them under Updates, beside what the world installed.

# zeromind.vote Upvote, downvote or clear your vote on a published world, asset or comment. Voting is how the library ranks things, so it is the cheapest way to make a good asset easier for the next person to find. Voting again replaces your vote; `0` clears it.

# zeromind.worldInfo Read a published world's record from ZeroMind — title, description, body, tags, visibility, score and your own viewer state. The read side of `zeromind.setMetadata`. Worth calling first, because `setMetadata` replaces the fields it is given rather than merging into them.

# Toolbox (asset type) A toolbox is a namespace folder that groups related `.tool/` children plus shared helpers. Toolboxes are the addressing layer for tools — every tool's identity is `<toolbox>.<name>`, so the toolbox name appears in every callsite. Toolboxes also own a `shared.module/` helper module that the toolbox's tools `require(".shared")` for common utilities (result envelopes, validators, formatters). ## When to use one - You have two or more related tools that belong together (an `anim` toolbox with `play` / `stop` / `list`; an `assets` toolbox with `compose` / `validate`). - You need a shared helper module exclusively used by a tool set. - You want a clean dot-namespaced identity for your tools (`my_tools.foo`, `my_tools.bar`). If you only have one tool and no shared helpers, you still need a toolbox — it's the required parent. ## Where it lives - Source: `/zero/source/.../<Name>.toolbox/` - Identity: `<Name>` (the `.toolbox` suffix strips). - Folder shape (container-style — open child set): - `README.md` — instance documentation. **Required.** - `.metadata` — agent-editable tags + free-form fields. **Required.** - `shared.module/` — optional shared helper module (`init.luau` + `README.md`). - `<x>.tool/` — any number of `.tool/` children. The validator permits unlisted children (`allow_unlisted: true`) so tool subfolders don't need to be declared per-name. ## How to create one ```luau tools.createToolbox({ name = "<Name>", description = "..." }) -- or the generic scaffold: asset.create("toolbox", "<Name>") -- Creates: /zero/source/<Name>.toolbox/ -- README.md (instance README template) -- shared.module/ (ok / fail result-envelope constructors) -- `folder` places it in a subfolder of /source; `into` nests it in a -- resolved `.package`: asset.create("toolbox", "<Name>", { folder = "tools" }) ``` Then add tools under it: ```luau local box = asset.resolve("<Name>.toolbox") asset.create("tool", "<toolName>", { into = box }) ``` ## How it operates 1. **Registration.** Writing into a `.toolbox/` folder indexes the toolbox. It becomes the parent namespace for any `.tool/` children. 2. **Tool identity composition.** Each child `.tool/`'s identity is `<toolbox>.<tool>`. Listing the toolbox's tools enumerates the children. 3. **Shared helpers.** Tools inside the toolbox pull `shared.module/` in via `require(".shared")` (relative require from the tool's `init.luau`). 4. **Hot reload.** Editing `shared.module/init.luau` reloads every tool in the toolbox (they all `require` it). Editing the toolbox folder structure (adding / removing tools) reflects in `tools.list` immediately. ## Discovery - `asset.list("toolbox")` — every registered toolbox. - `asset.inspect("<name>")` — child tools, source, this type README. - `ls /zero/source/<Name>.toolbox` lists the files the folder holds. - `tools.list()` — every tool across every toolbox. ## Authoring conventions - **Per-tool implementation lives in each `<x>.tool/init.luau`.** The tool's full function body — argument validation, the call into engine APIs, the return value — goes in `init.luau` with `--!desc` / `--!arg` / `--!return` / `--!example` annotations above the function. **Every exported function is declared `typed function`** — the keyword compiles to the runtime argument check, so a plain `function` accepts any input and reports success on garbage. Do NOT make `init.luau` a one-line forwarder onto a function defined in `shared.module/`. - Keep `shared.module/` thin: result envelope constructors (`shared.ok(value, formatted)`, `shared.fail(message, exitCode)`), argument validators, common formatters — anything genuinely used by more than one tool. Per-tool logic does NOT belong here. - Group by domain, not by surface — `assets` toolbox holds asset operations, `entity` toolbox holds entity operations. Tools that feel unrelated probably want different toolboxes. - Document the toolbox's surface in `README.md` — what problem space it covers, who calls into it, any shared invariants. ## Common pitfalls - **Missing parent toolbox.** Tools cannot exist outside a toolbox. Always scaffold the toolbox first. - **Cross-toolbox shared.** Each toolbox has its own `shared.module/`. Don't try to share helpers across toolboxes; if you need cross-toolbox helpers, factor them into a standalone `.module`. - **Toolbox identity.** Strip the `.toolbox` suffix in identity references (`my_tools`, not `my_tools.toolbox`). ## Related types - `.tool` — the required child(ren) of a toolbox. - `.module` — for cross-toolbox utilities. ## In the Inspector Tools: how many tools the box holds, whether it ships a shared module, what each tool does, and a link to each tool.

# Tool (asset type) A tool is a single agent-callable function whose schema is its `typed function` signature. Tools are the workflow surface — composed Luau operations that bundle multiple engine APIs into one named call, suitable for agents (and for use from `execute`). Each tool has a declared input shape, return shape, and a strict result envelope (`ZmToolResult`). **Every exported tool function is declared `typed function`.** The `typed` keyword is what makes the signature real: it compiles to a runtime dispatch wrapper that checks each argument against its declared type and raises on a mismatch. A plain `function` — even one carrying Luau type annotations — is checked by nothing at call time, so the tool accepts any input and reports success on garbage. See "The typed signature is the schema" below. ## When to use one - You're composing several engine APIs into a workflow that's worth naming and discovering (`tools.list`, `search_tools`). - You want an agent to be able to call this function by name without reading source code — the typed signature is the API contract. - The operation has clear success / failure modes that fit `{ exitCode, data?, stdout?, message? }`. If the function is just a Luau utility called from other code, use a `.module`. If it's stateful background work, use a `.service`. If it's pure GPU compute, use a compute `.shader`. ## Where it lives Tools nest under a `.toolbox/` parent — toolboxes are the namespace. - Source: `/zero/source/.../<Toolbox>.toolbox/<name>.tool/` - Identity: `<Toolbox>.<name>` (dotted form — the toolbox name is part of the tool identity). - Folder shape: - `init.luau` (or `init.lua`) — exports the function, and carries its schema in `--!desc` / `--!arg` / `--!return` / `--!example` annotations above it. The typed signature IS the tool's signature. **Required.** - `README.md` — instance documentation. **Required.** - `.metadata` — tool-level tier and tags. **Required.** ## How to create one Use the workflow tool that scaffolds the right `.tool/` shape under an existing toolbox: ```luau -- The `tools` global authors a tool inside an existing toolbox: tools.create({ name = "<name>", toolbox = "<Toolbox>", description = "What this tool does, agent-facing.", code = "return shared.ok(true)", -- the function body }) -- Or scaffold the folder manually: local box = asset.resolve("<Toolbox>.toolbox") asset.create("tool", "<name>", { into = box }) ``` Always nest under an existing toolbox — if you don't have one yet, call `tools.createToolbox({ name = "<Name>", description = "..." })` first. ## How it operates 1. **Registration.** Writing `init.luau` into a `.tool/` folder registers the tool with the tools registry. It becomes callable as `tools.use("<toolbox>", "<name>", ...)` from Luau, `use_tool { toolbox, tool, args }` over MCP, and `zero <toolbox> <name> [args]` from the engine shell. 2. **Schema validation.** The `typed function` signature declares the parameter shape. Its runtime dispatch wrapper checks each argument before the body runs and raises a message naming the argument, the expected type, and what arrived. 3. **Return envelope.** Tools MUST return `ZmToolResult`: ``` { exitCode = 0|n, data? = any, stdout? = string, message? = string } ``` `exitCode = 0` means success; non-zero means failure, with `message` carrying the human-readable reason. 4. **Discovery.** The tool surfaces in `tools.list()`, `search_tools { query: "..." }`, and `asset.inspect`'s `exposes:` section (parsed from the typed signature and the `--!` annotations). 5. **Hot reload.** Editing `init.luau` re-registers the tool. Subsequent calls see the new behaviour / schema. ## Discovery - `tools.list()` — every registered tool (any toolbox). - `search_tools { query: "..." }` — MCP-side tool search. - `asset.list("tool")` — same set, asset-style listing. - `asset.inspect("<toolbox>.<name>")` — signature, parameters, return shape, this type README. - `ls /zero/source/<Toolbox>.toolbox/<name>.tool` lists the files the folder holds. ## Authoring conventions - **Implementation lives in `init.luau`.** The tool's full function body — argument validation, the call into engine APIs, the return value — goes in `init.luau`. The toolbox's `shared.module/` is for genuinely cross-tool helpers (`ok` / `fail` constructors, shared parsers / validators), not per-tool logic. Do NOT make `init.luau` a one-line forwarder onto a function defined in `shared.module/`. - Use `shared.module/` in the parent toolbox for `ok` / `fail` result constructors. Don't hand-roll the envelope per tool. Pull it in with `local shared = require(".shared")` from any tool that needs the helpers. - Annotate every public function with `--!desc` / `--!arg` / `--!return` / `--!example` directly above the function — the LSP and toolbox surfaces extract these. - **Declare every exported function `typed function M.name(arg: T, opt: U?): R`.** This is not conditional on the signature being "clear" — a loose argument is the case that needs the checked contract most. Give the argument the type it actually accepts (a union, a named table type, a literal enum) instead of dropping to an unchecked `function`. - Keep tools focused. One tool, one named workflow. Split rather than grow. - Tag tools in the sibling `.metadata` (`{ "tags": [...], "tier": "core|content|specialized" }`) so `search_tools` can find them by domain (e.g. `entity`, `scene`, `assets`, `physics`). ## The typed signature is the schema The `typed` keyword compiles the function into a dispatch wrapper that validates arguments at call time. Without it there is no check at all, so the tool runs its body on whatever arrived and returns a success envelope built from garbage. Type each argument as narrowly as the operation actually accepts: ```luau export type Mode = "edit" | "play" export type SpawnOpts = { position: { number }?, parent: EntityRef?, count: number?, } --!desc Spawn a primitive and return the entities it created. --!arg kind Primitive shape to spawn. --!arg opts Placement and repetition options. --!return The spawned entity refs. --!example "cube", { count = 4 } typed function M.spawn(kind: ("cube" | "sphere" | "plane"), opts: SpawnOpts?): { EntityRef } ``` - **A fixed set of accepted words is a literal union**, never `string`. `("cube" | "sphere")` rejects `"Cube"` at the call and lists the accepted values in the error; `kind: string` accepts `"banana"` and fails somewhere deeper, or not at all. - **A structured argument is a named `export type`**, never `{ [string]: any }`. Naming it puts every field and its type on the tool's page and checks them on entry. - **A named type is only as strong as its fields.** `opts: DrawOpts` where `DrawOpts = { value: any }` passes for a table and checks nothing inside it — the same hole, one level down. The argument checker walks nested fields, so type each one; a type name is not a place to put the work off. - **A dispatch table keyed by an `op` string is several tools.** `{ op: string, [string]: any }` is one unchecked entry point wearing N signatures — split it so each operation carries its own checked arguments. - **An entity or asset argument is `EntityRef` / `AssetRef<kind>`**, never `any` and never a bare name string. - `any` is correct only for a value the tool genuinely does not constrain — a passthrough payload, arbitrary user data. It is not a placeholder for a type not yet written down. ## Common pitfalls - **A plain `function` export.** The tool registers and dispatches, so nothing looks wrong — it just never rejects bad input, and every call reports success. Declare it `typed function`. - **Annotations without `typed`.** `function M.f(x: string)` reads as typed and checks nothing at runtime; the annotation only informs the LSP. The keyword is what enforces it. - **Wrong return envelope.** Returning a raw value instead of `{ exitCode = 0, ... }` will be flagged by callers expecting `ZmToolResult`. - **Tool identity.** The fully-qualified identity is `<toolbox>.<name>`, NOT just `<name>`. Toolbox-less tools don't exist by design. - **Missing dependency.** Tools requiring another package / service must declare it; otherwise the call fails at runtime with a missing-module error. ## Related types - `.toolbox` — the required parent namespace for tools. - `.module` — for Luau libraries with no agent-facing schema. - `.service` — for stateful background work, not callable request/response operations. ## In the Inspector Tool: how the tool is called (its signature), what it does, each argument, what it returns, and its examples, with **Open** for its source.

# Module (asset type) A module is a reusable, stateless (or globally-stateful) Luau library that other code pulls in with `require()`. Modules are the unit of factored-out logic in a world: helpers, math libraries, format parsers, registries, shared algorithms. ## When to use one - You have logic you want to share across multiple components, services, scenes, or tools. - You have a registry, lookup table, or shared cache that callers all read from / write to. - You want a stable API surface (`M.fn`) other code can depend on. If the logic is bound to one entity, use a `.component`. If you want a named UI of fields rather than functions, use a `.preset`. ## Where it lives - Source: `/zero/source/.../<name>.module/` - Identity: the source path with `/` written as `.` and each segment's type suffix dropped — `/zero/source/demo/beats.module` is `demo.beats`, and `/zero/source/kit.package/beats.module` is `kit.beats`, the container's name kept and its `.package` suffix gone. `asset.create` returns this string, `asset.resolve(...).identity` reads it back, and the `require` forms below write it as `<identity>`. - Folder shape: - `init.luau` (or `init.lua`) — module body. **Required.** Returns a table (conventionally named `M`). - `README.md` — instance-level documentation. **Required.** - `.metadata` — agent-editable tags + free-form fields. **Required.** ## How to create one ```luau asset.create("module", "<name>") -- Creates: /zero/source/<name>.module/ -- init.luau (canonical `local M = {} … return M`) -- README.md (instance README template) -- `folder` places it in a subfolder of /source, and that subfolder -- leads the identity: `{ folder = "lib" }` produces `lib.<name>`. -- `into` authors it inside a resolved container (a package, a toolbox), -- whose own identity leads the same way: asset.create("module", "<name>", { folder = "lib" }) asset.create("module", "<name>", { into = asset.resolve("myPkg.package") }) ``` ## How it operates 1. **Registration.** Writing `init.luau` into a `.module/` folder indexes the asset and registers the module path with the resolver. 2. **Loading.** The first `require("<identity>")` runs the file's body and caches the returned table. Subsequent requires from anywhere return the **same table** — this is the shared-state lever for "module-local" registries. 3. **Hot reload.** Editing the file re-runs the module body and folds what it returns into the table already loaded, so that table keeps its identity: a caller that captured it with `require` reads the new source's functions and values through the reference it already holds, and a later `require` returns that same table. A key the new source drops goes away; a key something set at runtime stays. The body's own `local`s start again from their initial values, so state that must outlive an edit lives in `modules.state()` (`guides { path: "core/scripting-and-tasks" }`). 4. **Identity resolution.** A module is reached by its `<identity>`, and where the caller lives decides which spelling of it resolves. For a module in a **world**, from a caller in that same world — another module, a component, a scene entrypoint, or an `execute` chunk: - `require("<identity>")` — the identity on its own, resolved against the caller's own root. It carries every folder segment, so a module created with `{ folder = "demo" }` is `require("demo.beats")`. - `require("@root::<identity>")` — the same root-relative resolution, written out. - `require(".sibling")` — a module in the same folder, by its bare name; `..name` steps up one folder, `...name` two. Logs, stack traces and hot-reload notices name that same module `@local.source.<identity>` — its key under the world source root. The `<identity>` tail of that key is the form above, so a trace reading `@local.source.demo.beats` is `require("demo.beats")`. For a module in a **library** — content under `/zero/source/libs/@<lib>/` — `@<lib>::` addresses that library's root from anywhere: `require("@builtin::modules.transform")`. Mounting a world as a library moves its files under such a root and flips the caller root to `@<lib>::`, which is what keeps the root-relative forms above resolving across the move. ## Discovery - `asset.list("module")` — every registered module. - `asset.inspect("<name>")` — public functions, source path, this type README. - `ls /zero/source/<name>.module` lists the files the folder holds. ## Authoring conventions - Return a single `M` table from `init.luau`. Top-level statements with side effects run on first require — useful for one-time initialization, dangerous if they touch the engine before it's ready. - Write exported functions as `typed function`, not `function`: the argument types are enforced at the call and the checker knows the signature, so a caller's mistake is reported where they made it. - Annotate exported functions with `--!desc` / `--!arg` / `--!return` / `--!example` so the LSP, `tools.list`, and `asset.inspect` surface them. A function with no `--!desc` is reachable only by someone already reading this file. - Declare a VALUE with `Field.<kind>(default, mode, description)`, and a table whose members are reached through a metatable with `--!members <TypeName>` — the latter gives the surface its accepted member set, its type, and its documentation from one table. See `guides { path: "core/authoring" }` for all four rules and `modules/api/engine/entity.module/members.module` for a worked member table. - Keep module state in module-local upvalues or in `modules.state()`. Globals leak across reloads. Module-locals start again from their initial values with each hot reload; the table `modules.state()` returns is the same table on both sides of every reload. - Prefer focused modules over kitchen-sink modules. If two halves of a module have no shared state, split them. ## Common pitfalls - **Cyclic requires.** A `require` chain that loops will return the partial table (the half built before the cycle was detected). Design for one-way dependencies. - **Engine-time side effects.** Don't `entity.spawn` at module top-level — the engine may not be ready. Expose an `M.init` and call it from a scene entrypoint. - **Hot-reload + module-local cache.** A module that caches expensive computation in upvalues loses that cache on reload — fine for dev, but be aware in performance work. - **`init.lua` vs `init.luau`.** Either works, `.luau` is canonical. - **Writing one while play runs.** A `/source` write made while play is running lands on the play shadow, and a guarded play-exit discards it unless it is kept. One `.module` write shadows `init.luau`, the `README.md` and the `.metadata` together. `vfs.write(path, bytes, { durable = true })` skips the shadow, and `vfs.promotePlayShadow` keeps what is already on it — the `core/vfs` guide has the model and what each route costs. ## Related types - `.component` — for entity-bound state + lifecycle hooks. - `.service` — generates content you don't have yet (a mesh, sound, texture, …) via a metered provider. - `.tool` — for a single agent-callable function with a YAML schema. - `.package` — to group several modules + components + scenes into one shippable folder. ## In the Inspector Exports: what the module exports (name, kind, signature), parsed from its source without running it, with **Check** (the LSP's diagnostics for its entry file) and **Open**.

# shared Cross-tool helpers for the [name] toolbox. Every tool inside the toolbox can pull these in with `require(".shared")`. Holds the small set of helpers that more than one tool needs — typically the `ok(value, formatted?)` / `fail(message, exitCode?)` constructors that produce the canonical `[name]ToolResult` shape, plus any toolbox-wide parsers, validators, or shared state. Per-tool implementation stays inside each `<x>.tool/init.luau`; this module is not a place to forward logic from. ## Exports - `M.ok(value: any?, formatted: string?) -> [name]ToolResult` — success envelope (`exitCode = 0`, `ok = true`). - `M.fail(message: string, exitCode: number?) -> [name]ToolResult` — failure envelope (`exitCode` defaults to 1, `ok = false`). Types: - `[name]ToolResult = { stdout: string, stderr: string, exitCode: number, ok: boolean, value: any? }` - `stdout` — human-readable formatted output; empty when the op produces no text. - `stderr` — error message on failure; empty on success. - `exitCode` — POSIX-style exit code: `0` success, `1` generic failure, `2` bad arguments. - `ok` — `true` iff `exitCode == 0`. - `value` — structured return from the underlying op; `nil` for void ops. ## Usage ```luau local shared = require(".shared") function M.someTool(args) if not args.id then return shared.fail("missing id", 2) end return shared.ok({ id = args.id }, "created " .. args.id) end ``` ## Notes - Pure constructors — no engine calls, no state. Safe to call from any context. - Tools that opt into this shape get a stable envelope every other tool in the toolbox can rely on. Tools that do something custom can return whatever shape they want — `[name]ToolResult` is opt-in. - Per-tool implementations still own their own `--!desc` / `--!arg` / `--!return` / `--!example` annotations even when their result is constructed through these helpers.

# assetType (asset type) The `assetType` is the **type of types** — the meta-type that every `<typename>.assetType/` folder is an instance of, including itself. A `<typename>.assetType/` folder declares a new asset type called `<typename>`: its on-disk shape, its identity rule, and the structural contract instances of the type must satisfy. This type is self-hosting. `assetType.assetType/` conforms to its own schema — a `type.yaml` plus a `README.md` — so the type system is defined in terms of itself rather than a hidden engine special-case (the same way a C compiler is written in C). Every asset in the engine, including each `.assetType` definition, now resolves to a registered assetType: a `.material` resolves to `material.assetType`, and `material.assetType` resolves to `assetType.assetType`, which resolves to itself. ## Why it exists Assets used to be mapped to their type *implicitly*, by matching the folder suffix against a name-keyed registry. That match carried no stored link: nothing on a `Foo.material` recorded *which* `material.assetType` it was written against, so two worlds shipping a same-named type could silently disagree. Making `assetType` a real, resolvable asset closes that gap — the link from an asset to its type is now an explicit reference pinned in the asset's `.refs` sidecar (`via: "asset_type"`), exactly like every other dependency. ## Where it lives - Source: `/zero/source/.../<typename>.assetType/` - Identity: `<typename>` (the `.assetType` suffix strips from the identity; the folder retains the suffix on disk). - Folder shape: - `type.yaml` — the structural spec the validator reads. **Required.** - `README.md` — type-level documentation. **Required.** - `about.yaml` — three short plain-language texts saying what the type is for (see "Say what your type is for" below). Every built-in type ships one. - `behavior.luau` — optional behavior/scaffolding module. - `template/` — optional canonical placeholder body the templater copies into a new asset of the type. - `<name>.module/` — optional shared code the type ships to **every instance** of it, conventionally `shared.module/` (see below). ## Shared code its instances reach (`asset.containing` + `.modules`) A type ships code every instance of it uses by declaring the modules in its own `behavior.luau`, as a map of tracked `require`s: ```luau -- inside <typename>.assetType/behavior.luau M.modules = { shared = require(".shared") } -- the sibling shared.module/ ``` An instance reaches it with one location-independent line: ```luau -- inside any foo.<typename>/init.luau local api = asset.containing(__FILE__).modules.shared ``` `__FILE__` is the chunk's own VFS path; `asset.containing` resolves the calling asset, and `.modules.<name>` follows the instance's pinned `typeRef` (the type's **guid**, recorded in the instance's `.refs` as `via = "asset_type"`) to the module its type declares. Because resolution follows that link rather than a category name, the same line in an instance of a different type resolves to that type's module, and identically-named modules in two types never collide. `asset.typeRef(target)` reads that guid for any target; `asset.resolve(asset.typeRef(target))` gives the full `AssetRef<assetType>`. See `assetTypes/README.md` § "Shared code: type-owned modules" for the full mechanism. ## How to create one Authoring a new asset type is just creating a `<typename>.assetType/` folder under `/zero/source/`. The engine registers `<typename>` as a category **the moment the folder is written** — no engine restart, no Rust change, and it works for built-in (`@builtin/assetTypes/`) and user-defined types identically. Once `<typename>` is registered, `<name>.<typename>/` folders are recognised as assets of that type and resolve their `asset_type` link back to this definition. Creating a `<name>.<typename>/` folder *before* its `<typename>.assetType/` exists fails fast: the suffix has no registered type, so the folder can't be a valid asset. Author the type first. ## Say what your type is for (`about.yaml`) Every type carries a small `about.yaml` beside its `type.yaml`, and the README you write for the type documents how to author an asset of it. Both are required, and both are meant to be written as you make the type, while you know what it is for. `about.yaml` answers three questions in plain words, one key each: ```yaml intent: "Sets the typeface of the text in your game: UI, labels, signs and 3D lettering." function: "A font, from a TTF, OTF or WOFF file, made available to all of Zero's text, including 3D text." usage: "You choose it by name for your UI or your text, and the text appears in that typeface." ``` - **`intent`** is what the type is for in someone's game. Name the whole range of things it covers, in the words a game maker would use for them. - **`function`** is how it works today: what an asset of the type is made of and what the engine does with it. - **`usage`** is what a person or an agent does with one: how they pick it, place it, call it, or hand it to something else. A few habits keep it useful. Write about the type as a whole, so the text holds for every asset of it, and leave out any one asset's name. Say what the type does right now. Stay with words a game maker would say, and mention a file name or a call only where a game maker would know it. The limits are in bytes: `intent` 800, `function` 1500, `usage` 1200. Each is generous, and a few sentences usually say it. Why bother: agents working in a world read these three texts to learn what your type is for, so they reach for it when it fits and use it the way you meant. People searching find the type by what they want to make, and the three texts let them tell at a glance whether it is the one they need. `asset.create("assetType", name)` scaffolds the file with all three keys, and a README whose first paragraph is a `[[describe]]` note. Each value starts with `[[describe]]` followed by a note on what to write; replace the whole value with your own words. A value or a README line that still starts with `[[describe]]` counts as not written yet, which the push's check of each asset it carries against its type reports, naming the file. A type you leave as it was is not asked, so older types stand. Many types at once, or one you would rather not write by hand: `services describe` lists the types that lack these texts and what filling them costs, and `{ mode = "all" }` writes them into the same files, where you edit them like anything else you wrote. Where the texts show up: `asset.inspect("<typename>", "assetType")` returns them as `detail.about`, `assetTypeRef:getAbout()` returns them as a table with the keys `intent`, `function` and `usage`, the type's `types/<typename>` guide page ends with an "About this type" section holding them, and the Inspector's Type section lists them at the top. The guide page is this README plus that section, so a README that explains the type well and an `about.yaml` that says what it is for read well together. ## Ask your assets to say what they are A type can ask each of its assets to carry a description: a file, written by the author or generated, that says what that asset is and what it is for. The people and agents who find an asset read it to decide whether it fits, and the author knows what it is for at the moment of making it. **1. Declare the file with a `described` check.** This is the whole requirement: ```yaml files: required: - path: "README.md" # any file name works kind: "file" content: - { check: "described", message: "Say what this widget is for and where it goes." } ``` With that in place: - An asset whose file is missing, empty, or still has a line starting with `[[describe]]` does not meet the type's requirements. `asset.validate` names it, `zm status` and `world.publishBlockers()` list it, and a push that carries it is refused with `message`. - `services describe` finds it (`mode = "find"` lists it and the price) and can write the description for it (`mode = "all"`). It writes only this file. For a YAML file that holds several texts, name the keys and their limits in bytes, the way this type does for `about.yaml`: ```yaml content: - check: "described" keys: - { key: "intent", max_bytes: 800 } - { key: "usage", max_bytes: 1200 } message: "Write intent and usage." ``` `headings` names sections a Markdown file must have. `assetTypes/README.md` has the full check. **2. Optionally, steer what gets generated with a `describe:` block:** ```yaml describe: guidance: "Say what the widget shows, what input it reacts to, and where it fits in a UI." examples: - "<identity of an asset of this type whose description reads well>" ``` `guidance` says what a description of your type covers, and `examples` names assets whose descriptions show the shape you want. Without the block, generation still works from the general describing guide and the check's `message`. An example is an asset of your type in the library whose description is a true, written one, never a scaffold's placeholder, and never the asset being described. When the library has none, leave `examples` empty rather than name one that is not. A type whose assets the model cannot perceive (a sound it cannot hear, a motion it cannot see) says so in `guidance`: the description comes only from what the asset's own files state, such as its name and the `.metadata` where a generation service records the prompt that made it, and when they state nothing the model answers `cannot` with that reason. `services describe` then fails that one asset with the reason and leaves its file as it was. **3. Start the file unwritten in your template.** Put a heading and one line that starts with `[[describe]]` and a short note on what to write, in `template/<file>`, so a new asset starts unwritten rather than with text that only looks written. Do not put example content in it: every new asset carries the template verbatim, and the same text on many assets makes them impossible to tell apart in search. Types whose assets say what they are through their own content (a mesh, a texture, a sound) leave this out: declare nothing and nothing is asked. ## The `behavior.luau` contract `behavior.luau` is the type's code. It returns ONE table, and the keys below are the ones the framework reads off it for EVERY type — the surface you get by declaring them. Anything else on the table is your own: reachable by name through `require("@builtin::assetTypes.assetType.shared.ref").loadTypeModule("<typename>")` for a system that knows your type (`computeShader` publishes `dispatchKey` that way), and never called by the framework. ```luau local M = {} M.ref = { ... } -- methods on every AssetRef of this type M.modules = { ... } -- shared code the instances reach M.global = {} -- reserved key; ship the empty table function M.onCreate(name, opts) ... end return M ``` ### The tables | Key | Shape | What the engine does with it | |-----|-------|------------------------------| | `M.ref` | `{ [name] = function(self, ...) }` | Every function becomes a method on every `AssetRef` of this type: `ref:name(...)`, with `self` the ref. This is how a type gives its instances an API. Two names in here are contracted — see below. | | `M.modules` | `{ [name] = require(".sibling") }` | Shared code the type's instances reach through `asset.containing(__FILE__).modules.<name>`, resolved by the instance's pinned `typeRef` guid. See the section above. | | `M.refShapes` | `{ [method] = "TypeName" }` | Declares the result type of a `M.ref` method so the LSP can check what a call site does with it. See the `M.refShapes` section below. | | `M.events` | an events schema | The events an ASSET of this type fires, declared the way a component declares its own. Readers subscribe through `ref.events.<name>:connect(...)`; firing authority stays with the type. Keyed by the asset's guid, so every resolver of the same asset shares the signals and a re-resolved ref re-attaches to subscriptions already there. | | `M.namePattern` | a Lua pattern string | The name shape `asset.create` enforces for instances of this type, replacing the default `^[A-Za-z][A-Za-z0-9_]*$`. | | `M.global` | `{}` | Reserved. Ship the empty table. | ### The lifecycle hooks Each is optional; a type that omits one costs nothing. The engine calls them: | Hook | Signature | When it fires | |------|-----------|---------------| | `M.onCreate` | `(name, opts) -> { [filename] = contents }` | On `asset.create("<type>", name, opts)`. Returns the files that scaffold the new instance, as a map of relative path to contents; the framework writes them. The `opts` type annotation is the schema `asset.create` validates the caller's arguments against, so annotate it. | | `M.onReplace` | `(dest, files) -> { [filename] = contents }` | On an `asset.create` that writes over an asset already at `dest`, after `onCreate`. Receives the files `onCreate` produced and returns the files to write, so a type that re-derives its content (a rig re-imported from its source file) can carry what an author added to the asset it replaces. Optional. | | `M.onRegister` | `(self)` | Once per instance, the first time it registers: on `engine.onWorldLoaded` for instances already in the world, immediately on a live `asset.create`, and when an instance arrives after that sweep (installed, pulled, or synced from a peer). Guarded by the instance's path, so a double trigger never double-registers. An instance that leaves the runtime releases the guard, so one arriving at the same path again registers. This is what makes "write an asset into the world and it takes effect live" work for content that registers into a runtime registry. The `@builtin` library is excluded from the sweep. | | `M.onChange` | `(ref, change)` | On every VFS write to a file INSIDE one of this type's instances. `change` is `{ path, asset, type, kind, origin }`: `kind` is `"edited"` or `"seeded"`, `origin` is `"local"` or `"remote"` (an importer runs on the originator only). **Filter on `change.path`**: the hook fires for any file under the folder, so act on the one you care about. It runs as its own task and may wait on what it reads: a `vfs.read` of bytes only the blob store holds (a binary file on the web build) fetches them. The writes to one asset reach the hook in the order they were made, each once the hook before it has finished. A re-entrancy guard suppresses writes back into the same asset routed inline from the hook, and a write the hook makes is routed on a later frame like any other, so the hook must be convergent on its own: diff the meaningful state and short-circuit while your own regeneration is in flight. | | `M.onDelete` | `(ref)` | When an instance of this type leaves the runtime: it is deleted, or the engine swaps away from the world binding that held it. Its files are gone from `/zero/source` by then. A removal routed while the instance's `onChange` is waiting reaches `onDelete` once that hook, and every write queued behind it, has finished. On a swap the instance still exists in the world it belongs to, and a VFS write the hook makes reaches the world now bound. | | `M.validate` | `(assetRef) -> { { code, message, severity? } }` | On `asset.validate`, after the structural `type.yaml` check, for the type's own SEMANTIC validation. `severity` defaults to `"error"`; error-severity problems flip `ok` to false, warnings do not. A hook that raises or returns a non-table is itself reported as a `validate.hook_failed` error. `world.push` runs this per user asset, so declaring it enforces your type's rules at publish time with no further wiring. | ### The two contracted `M.ref` names Most `M.ref` methods are your type's own surface: name them what you like, return what you like. Two are read by the engine and mean the same thing for every type, so their shape is fixed: - **`instantiate(self, target?, opts?) -> (root, idMap)`** — makes an instance part of the scene. Defining it is the whole opt-in: `ref:canInstantiate()` is true exactly when it exists. Its **return is a contract** — see the next section. - **`inspect(self) -> detail`** — the type-specific half of `asset.inspect`. See its section below. ### Names a type cannot shadow Some keys resolve on every `AssetRef` before per-type dispatch, so an `M.ref` entry of the same name is never reached: `canInstantiate`, `getSource` / `getBytes` / `getText`, `exists`, `deps`, `meta`, `runtime`, `events`, `modules`, `typeRef`, and the residency flags `has_backing_asset`, `has_runtime_changes`, `cpu_resident`, `gpu_resident`. These are the behaviours every asset must expose identically, which is why they win. ### Reloading A `behavior.luau` edit ripples to existing refs with no restart: dispatch reads `mod.ref` fresh each time and `require`'s cache is re-run in place. A type whose folder appears at runtime is picked up on the next dispatch — negative results are not cached either. ## The names your type's assets hold (`references:`) An asset that names another asset by a string depends on it: the named asset travels with it into a pack or a pull, and a name nothing answers to is an unresolved dependency `worldValidation` reports and the push gate refuses. The engine reads `require(...)` and the asset lookups on its own; a name your type's format or API carries anywhere else is one you declare, in `type.yaml`: ```yaml references: # A top-level key of this type's own files that holds a name (or a table of them). keys: - { key: "shader", type: "shader" } # A call's argument, counting from 1, wherever the call is written. args: - { call: "g:node", position: 2, type: "procNode" } # A field of the options table a call takes. fields: - { call: "fx.beam", field: "material", type: "material" } ``` `type` is the category the name resolves in, one of `asset.categories()`. An argument declared once per category, at the same `call` and `position`, takes the name from whichever category answers. A key or a field holds one category: declared again with another `type`, it takes the later one. The block is declared as the type registers, when the library or the world holding it is laid into the VFS, so every reference table reads it whatever script has or has not run. `asset.declareReferenceKey`, `asset.declareReferenceArg` and `asset.declareReferenceField` declare the same things from a script, for a surface that is no type's. ## What search does with your type (`indexing:`) A type declares what search embeds for its instances. **This is not optional and there is no useful default**: ZeroMind runs your declaration and adds nothing of its own, so anything you do not point at is absent from the index — silently, and for every instance of the type forever. Twenty types once shipped with no `indexing:` block and every instance of them was unfindable. A type whose instances are never searchable (a run record, a log) says so with `indexing: none`; every other type declares a recipe. A type without an `about.yaml` beside its `type.yaml` refuses every push that carries it, whether or not the push edited the type. Texts in it that are not written yet follow the rule every `described` file follows: they refuse the push that edits, stages or commits the type. Two words carry the whole thing, and they are the same two the search tool exposes: - **`identity`** — what an instance IS. For anything you can look at, that is the picture (`content:` + `modality: image`, matched directly by a text query). For everything else it is the authored text that says what it is. - **`capability`** — what it DOES and how it is made. Code, settings, the model-written summary of them. A type with no behaviour has no `capability` entry. A type with nothing to look at has no image. Leaving a slot empty is a statement; filling it with whatever happens to be lying around is not. The one you have to decide when authoring a type is: *for an instance of this, what is the thing a person would recognise it by, and what is the thing it does?* A texture answers "the image" and "its compression settings". A module answers "its README" and "its code". Write those two answers into `indexing:` and the rest follows. Three specifics worth knowing before you write one: - **`derive` is instructed by this type's own `README.md`.** A model reads an instance's source and writes a description; what it embeds is the description, not the source. It follows your README to know what it is looking at, so a type whose README says what its instances are gets good derivations for free. There is no prompt to name. - **`derive` loses detail.** It keeps the main technique and drops secondary ones. If the source is code you want searchable by its own vocabulary, declare the same files a second time as `capability` with `extractor: verbatim`. Two entries, same role, different failure modes. - **Never `source: { field: name }`.** A filename is one or two words with no usable embedding, and a corpus indexed that way answers "language runtime" with `say_runtime_2.soundClip`. `facets:` is the second stage: a `file:` embedded whole (`.metadata`, so keys nobody declared still get indexed) plus computed keys that state a value for every instance including `false` — the raw file can imply "not rigged" and can never say it. The full schema, every extractor and the facet sources are in [`assetTypes/README.md`](../README.md); the scaffolded block with inline guidance is in [`template/type.yaml`](template/type.yaml). ## A container whose contents work together (`system: true`) A type that is a container can say its contents are one working whole by declaring `system: true` at the top level of its `type.yaml`. `package` declares it: the components, modules, scenes and tools a package ships are parts of one system. The declaration is plain data, read from the decoded `type.yaml` (`require("@builtin::assetTypes.assetType.shared.declaration").of("package").system`), and a type that leaves it out is an ordinary type. ## What your type looks like (`preview:`) A type declares how its instances are pictured, and the engine makes the picture when something needs it: staging an instance whose `preview.png` is missing or pictures content it no longer holds queues a render, a view that shows the instance asks for one, and `ref:preview()` renders one on demand. An edit renders nothing on its own. Each `preview.png` records the content it pictured, which is how a stale one is told from a current one. The preview studio owns the light, the backdrop, the framing and the camera, and nothing in the world reaches it, so an instance pictures the same in every world. Declare one of four recipes: | `kind` | The picture is | Your type provides | |---|---|---| | `instantiate` | the asset stood in the studio through its own `instantiate` | `ref.instantiate` | | `image` | a file the instance holds, fitted to the frame, nothing rendered | `source.files`, the candidate files in order | | `surface` | the asset painted on a builtin mesh | `mesh`, and `ref.previewMaterial(self) -> { material }` | | `custom` | whatever `ref.preview(self, opts)` returns | `ref.preview` | ```yaml preview: kind: surface mesh: sphere ``` A scene-instantiable type that declares nothing still answers `ref:preview()` through its `instantiate`, but persists no picture: the declaration is what makes the engine keep one. List `preview.png` among the type's files so an instance may hold it. The picture is findable only when `indexing.content` names it. The two are separate statements, and neither is derived from the other: ```yaml indexing: content: - role: identity modality: image source: { file: "preview.png" } ``` `@builtin::assetTypes.assetType.shared.previewRecipe` reads the declaration; the scaffolded block with inline guidance is in [`template/type.yaml`](template/type.yaml). ## Typing a result from the instance (`M.refShapes`) Every method on `M.ref` is checked against the type its `--!return` names, and every asset of the type gets the same one. That is right for most methods and wrong for the ones whose result is shaped by the ASSET: a method answering one entry per child folder, per row of a config, per binding an input map declares. The widest true annotation for those is `{ [string]: Thing }`, and an indexer accepts every key — so a caller's typo reads as valid and nothing reports. `M.refShapes` lets the type state the result per instance. Each entry is `function(self) -> (typeExpression, source?)`: a Luau type expression for THIS asset, and the module whose type vocabulary the expression uses. Read the asset; never run it — stating a type must not take effect. ```lua -- inputMap.assetType/behavior.luau — the shipped example. -- `activate()` hands back one handle per control the map declares. M.refShapes = { activate = function(self): (string, string) local names = {} for _, control in ipairs(M.ref.controls(self)) do table.insert(names, control.name .. ": Handle") end if #names == 0 then return "", "" end return "{ " .. table.concat(names, ", ") .. " }", "@builtin::modules.zinput.scheme" end, } ``` With it, `map.jump:onPressed(fn)` resolves and `map.noexisting` is reported with the map's real controls. Without it, both pass silently. ### What the call site has to say A per-instance type is matched by the asset's IDENTITY, so it applies only where the reference the method is called on says WHICH asset. Two spellings do: ```lua -- a component field, whose declared default names the asset public = { map = Field.assetRef("inputMap", "@builtin::inputMaps.default", Sync) } local controls = public.map:activate() -- typed for THAT map -- an annotation, naming category and identity local m: AssetRef<"inputMap", "@builtin::inputMaps.default"> ``` `asset.resolve("<identity>", "<category>")` carries the CATEGORY, so the methods the category defines are checked on the result — but not which asset it found, so a per-instance result keeps the category's declared return. A reference that names no asset (`asset.resolve(someVariable)`, a value passed in as a parameter) carries neither, and calls on it are unchecked. That is the same rule everywhere: the checker states what the code states, and a name computed at runtime states nothing. ### The result is a value, not a binding The type belongs to the expression, so it travels the way any inferred type travels. Indexing the call's result is checked; stashing it in a module local and indexing it from another function is not, because the local's declared type is what carries across — and `any` (or no annotation) carries nothing: ```lua -- checked: `d.greting` is reported function awake() local d = public.dialogue:lines() d.greeting:say() end -- NOT checked: `lines` is a module local typed `any` local lines: any = nil function awake() lines = public.dialogue:lines() end function start() lines.greting:say() end ``` Bind what you need at the call site and the names stay checked in both places — the asset-derived type at the boundary, ordinary scoping after it: ```lua local lineGreeting = nil function awake() local d = public.dialogue:lines() lineGreeting = d.greeting -- `d.greting` is reported here end function start() lineGreeting:say() end ``` ### When nothing is reported and you expected something From a call site, a type that is correct and a type that was never published look the same: no diagnostic either way. `require("@builtin::assetTypes.assetType.shared.refShapes").published()` answers which it is. It returns two maps — the category surfaces, and the per-asset results keyed by identity and then by method: ```lua local shapes = require("@builtin::assetTypes.assetType.shared.refShapes").published() shapes.categories.dialogue --> "{ lines: () -> any, lineNames: () -> { string } }" shapes.returns.Shopkeeper.lines --> "{ browsing: Line, farewell: Line, greeting: Line, wares: Line }" ``` An identity absent from `returns` was never published for, which is a different thing from published-and-correct — and the reason to look here rather than at the call site. The answers are recomputed when an instance is written, so a control added to a map reaches the checker with no restart. Only types that declare `refShapes` are read per instance, and at most 64 assets of one type are — past that the type keeps its declared return and the engine log names what was dropped. ## The instantiate hook (`M.ref.instantiate`) — a contracted return A type opts into becoming part of the scene by defining `instantiate` on its `ref` table. That is the whole opt-in: `ref:canInstantiate()` is true exactly when the hook exists, so consumers offer a scene path — an `Asset.source` field, a viewport drop, a tool argument — by CAPABILITY rather than by a list of type names. Unlike `inspect`, this hook's **return is a contract**. A caller writes one piece of code against every instantiable type, so what comes back cannot vary by type: ```lua -- behavior.luau local Instantiable = require("@builtin::assetTypes.assetType.shared.instantiable") local M = {} M.ref = { instantiate = function(self, target, opts) local root = Instantiable.root(self, target, opts) -- IN: the base opts -- ... compose whatever this type is, under `root`, NOW ... return Instantiable.result(self, root, idMap) -- OUT: the contract end, } return M ``` **IN.** `target` is an owning entity ref: the instance lands under (or, for a hierarchy type, onto) that owner. With no target the type spawns a fresh root. `position`, `rotation`, `scale`, `name` and `temporary` mean the same for every type — `Instantiable.root` applies them to a root you mint, `Instantiable.place` to one you adopt, so you never re-read the spec. Honour more opts of your own if your type needs them, and document them in the hook's `--!arg` docs. **OUT.** Return `(root, idMap)` through `Instantiable.result`: - **`root`** — the composed root, as an `EntityRef`. Composition is **synchronous**: everything your type builds is live when you return, so the caller can parent to it and read its components in the same statement. Do not defer the work to a component's `awake` and return an empty shell — a root that is not live is refused. - **`idMap`** — the `originalId -> runtimeId` map naming what you spawned, or nil for a type with no addressable children (`result` normalises it to `{}`). **A caller never receives nil.** A component that re-composes your asset on every load keeps this map and passes it back in, which is how a cross-entity reference into the composition survives a reload. `AssetRef` runs every `instantiate` through `result` on the way out whether or not your type called it, so returning something else fails at your own call rather than handing a caller a nil root. Calling it yourself is still how you say what you return, and running it twice changes nothing. `@builtin::assetTypes.assetType.shared.instantiable`'s README is the full reference for both halves. ## The inspect hook (`M.ref.inspect`) `asset.inspect(ref)` resolves `ref`, builds a common envelope shared by every asset (`identity`, `name`, `guid`, `source`, `typeName`, `typeDefinitionPath`, `scope`, `origin`, `description`, `tags`), then calls the resolved type's own inspect hook — `M.ref.inspect(self)` on `behavior.luau` — for the type-specific `detail`. The hook returns *only* `detail`; the framework fills in everything else: ```lua -- behavior.luau local M = {} M.ref = { inspect = function(self) -- self.path is the asset's own folder. Parse the asset's OWN -- files — source text, a native payload header, its `.metadata` -- — never runtime state (a live component instance, a GPU -- upload, a compiled schema): inspect must work on an asset that -- hasn't been compiled, uploaded, or registered yet. return { -- type-specific fields, whatever this type wants to surface } end, } return M ``` A type that omits `M.ref.inspect` yields the generic record: the envelope alone, `detail = nil`. That's a valid, working state — not an error — but it means agents calling `asset.inspect` / `tools.use("assets","describe", ...)` on an instance of the type see only identity and scope, none of what makes an instance of it meaningful. Declaring the hook is what makes a type's instances inspectable for what they actually are. A hook that raises leaves `detail = nil` and sets `record.warning` to the error text — `asset.inspect` itself never raises for a resolved ref. ## Discovery - `asset.list("assetType")` — every registered asset type. - `asset.inspect("<typename>")` — the type's identity, source path, and this README, plus its `about.yaml` texts as `detail.about`. - `asset.resolve("<typename>", "assetType")` — the `<typename>.assetType` asset itself (used by the validator to find the type's `type.yaml`). ## Related - `assetTypes/README.md` — the full `type.yaml` schema and validator rules. - `@builtin::assetTypes.assetType.shared.instantiable` — the instantiation contract's shared implementation, both halves. - Every other `*.assetType/` here — the concrete types built on this meta-type. ## The Inspector a type ships Every type names the file its Inspector sections come from with `inspector: { type: "inspector.luau" }` in its type.yaml. `asset.create("assetType", name)` scaffolds the block and an `inspector.luau` whose Contents section lists an asset's files, built from `ctx.parts`. `asset.validate` on a type that names none reports `assetType.inspector_required` (an error for a `@builtin` type the engine's library authors; a warning for a world's own, and for one the library carries by reference, which the world that published it answers for), and one whose file does not load `assetType.inspector_invalid`. ## In the Inspector Type: what the type.yaml declares (suffix, container, primary files, the settings and inspector blocks), whether the type ships a behavior, how many instances it has, and **Open** for its files. Schema: the settings every instance carries, as read-only typed controls at their defaults (a type whose schema is per instance says where it is declared). Instances: a link to each of the first 20 assets of the type, and how many there are when there are more.

# world_vcs Pure-Luau wrapper around the `__spacetime_vcs.*` FFI primitives. Composes the low-level stage / commit / push reducer chain into the headline `world.add` / `world.commit` / `world.push` / `world.diff` / etc. API. The prelude grafts these onto the engine's `world` namespace at boot via `M.installInto(world)` — callers use the grafted methods on `world.*`, they don't `require` this module directly. This module is the ONLY place where the public `world.*` VCS API is defined. Future context-gating (only editor-scope VMs may invoke `world.commit`, components are denied, etc.) lives here as Luau-side checks. The Rust-side primitives stay one-to-one with module reducers and don't carry gating logic. ## Exports - `M.installInto(world: WorldNamespace)` — graft the entire VCS surface (`add`, `add_all`, `unstage`, `discard`, `commit`, `push`, `head`, `status`, `log`, `show`, `diff`, `affirm`, `trash`, `restore`, `stash`, `stashes`, `stashPop`, `stashDrop`, `reset`, `list`, `installLibrary`, `updateLibrary`, `checkUpdates`, `reviewUpdate`, `update`, `uninstallLibrary`, `installAsset`) onto the supplied namespace. After install, the following are callable on `world.*`: - `world.add(paths: string | { string })`: stage one path's manifest row, or each of a list of paths (asset-aware: expands to the asset family). A list stages every row its paths select once, so several files of one asset stage that asset's family once. Staging is advisory: a path another staging area holds is taken out of that area, whichever account opened it and whether or not its session is open, and named in the report's `released` (`stage`, `account`, `same_account`, `session`, `live`); a take from another account's area warns, naming that account, the area and its session. A staged path a caller of another account is writing now is named in `written` and warned about. The report is `{ staged, carried, released, written }`. - `world.add_all(opts?)`: stage every dirty manifest row, whoever wrote it, each with its asset family; conflicted rows stay out, and the call returns them. Staging is advisory: a path another staging area holds is taken from that area, whichever account opened it, and a row a caller of another account is writing is staged like any other. The calling account's own agents and engines never warn each other; a take from another account's area, and a staged path another account's open session is writing, warn once per area or caller. A second return value reports the call: `staged` (the paths it added), `held` (each conflicted path with its `reason`), `released` (each path taken from another staging area, with that area as `stage`, its row id as `stage_row_id`, its `account`, `same_account`, its `session` and whether that session is `live`) and `written` (each staged path a caller of another account is writing now, with `by` and `account`). Its cost follows the size of the dirty set: a fixed number of working-tree reads, and its stages and releases sent in batches. - `world.unstage(path: string)` — remove a path from the staging area. A path the calling area does not hold that another staging area does is taken out of that area, whichever account opened it; the call returns `{ released }`. - `world.stageVersion(rev, path)` — `git reset <rev> -- <path>`: the staging area's entry for the path becomes the revision's version, and a version the branch head holds (`HEAD` itself) unstages the path; the working tree stays. - `world.discard()` — drop the implicit stage without committing. - `world.commit(message: string) -> string` — open-or-resume stage, set message, materialise commit. Returns the new commit id (ULID). - `world.push(commitId: string?, opts: StageOpts?) -> (string?, string)` — push one or all unpushed commits to ZeroMind. `opts.stage` names the caller's own staging area: the pre-push content gate refuses over the assets that area holds or committed and publishes the rest carrying their shortfall, named back with the area holding each. Returns the pushed ZM commit id and the verdict `"published"`, or the verdict `"already-published"` when the remote already carries what the call would have published — with the commit's existing ZM id for the single-commit form, and a nil id for the whole-stack form. - `world.head() -> string?` — current branch HEAD commit id, or nil. - `world.vcsStatus() -> StatusResult` — dirty + staged + untracked entries. A file whose bytes are the head's and whose reference table is not (a library pin moved, or an asset it references changed) is listed with `reason = "references moved"`, staged like any change, and committed with what moved it: `world.commit` refuses a commit holding that change without the file, with a `dep.stale_references` entry per file. (Named `vcsStatus`, not `status`: `world.status()` is the runtime-snapshot accessor from `world_status.module`.) - `world.log(opts: LogOpts?) -> { CommitRow }` — `git log`: every commit reachable from `opts.rev` (default `HEAD`) through both parents, newest first; `opts.path` keeps the commits that touched one file. - `world.revParse(rev: string) -> string` — `git rev-parse`: the commit `HEAD`, a branch, `origin/<branch>`, a commit id or a unique prefix names, with `~N` / `^` / `^2` after it. - `world.show(...) -> any` — `git show`-style: commit metadata + diff, or path bytes via `<rev>:/path`. - `world.diff(...) -> any` — `git diff`-style: working / staged / revision-vs-revision, with `--stat` / `--name-only`. - `world.diffUpstream(root: string) -> { UpdateFile }` — your changes to an installed asset against the version it was installed from. - `world.createBranch(name, fromCommit?)`, `world.branches()`, `world.remoteBranches()`, `world.deleteBranch(name, { force? })`, `world.renameBranch(old, new, { force? })` — `git branch` and its `-r`, `-d` / `-D`, `-m` / `-M`. A rename that fails part-way is undone, leaving the branches as they were. - `world.checkout(branch: string) -> string` — `git checkout <branch>`: the caller's uncommitted changes and staged entries come along, or the switch refuses with git's message, moving nothing. `world.checkoutSide(path, "ours" | "theirs")` takes one side of an unmerged path; `world.checkoutPaths(rev, paths)` writes and stages paths as a revision holds them. - `world.merge(source: string, opts: MergeOpts?) -> MergeResult` — `git merge` into the session's branch: a fast-forward when it can (`noFf` / `ffOnly`), else a merge commit; a local change on a path the merge rewrites refuses it. `world.mergeAbort()` takes back what a conflicted merge wrote. - `world.affirm(token: string)` — consume an affirmation token returned by a destructive op. - `world.trash() -> { TrashRow }` — list trash entries. - `world.restore(handle: any)` — restore a trash entry by row_id. - `world.trashEmpty() -> number` — delete the trash entries your own operations put there, for good, in one transaction; other callers' entries stay. - `world.stash(label: string?) -> StashPushResult` — `git stash push`: save the caller's dirty + staged state into a stash and take those paths back to their committed version. Binary and large content is saved by its stored blob, so applying the stash brings it back byte-identical. - `world.stashes() -> { StashRow }` — list every stash in the world. - `world.stashApply(ref?)` / `world.stashPop(ref?)` / `world.stashDrop(ref?)` — `git stash apply | pop | drop`, defaulting to the caller's newest stash; `ref` is a row id or `stash@{n}`. A drop snapshots the stash to trash. - `world.reset(target: string, opts: ResetOpts?) -> ResetResult` — `git reset --soft | --mixed | --hard` to any revision; the commits the head leaves behind become trash entries. - `world.list() -> { WorldEntry }` — every world the authenticated user has access to. - `world.installLibrary(opts: InstallLibraryOpts) -> InstallLibraryResult` — declarative cross-world dependency marker. - `world.updateLibrary(name: string, ref: string?) -> UpdateLibraryResult` — move an installed library (`@builtin` included) to the commit `ref` (default `main`) resolves to in the library's world: rewrites the marker, waits until the engine holds the library at that commit (an `@builtin` pin table is read, another library is mounted), and derives again the reference tables of the world's own sources that name it; a ref resolving to the commit already pinned changes nothing. It refuses while play is running or in a runtime-profile session, and one move per library runs at a time. Returns `{ name, from, to, changed, rederived }`; a pin already at that commit is left untouched (`changed = false`). - `world.checkUpdates() -> ({ UpdateReport }, { UpdateSkip })` — the units with an update available, read-only. A library is one unit: its marker's `requested_ref` (default `main`) resolves in the library's world to a commit other than the marker's `resolved_commit` (`{ kind = "library", library, from, to }`; apply with `world.updateLibrary(name)`). An installed asset is one unit per install root (its reference table marks it): its recorded version differs from the newest version of the asset at its origin, one lookup per root (`{ kind = "asset", root_path, root_guid, display_name, from, to }`; apply with `world.update(<root path>)` (`zeromind.update`), which installs the root's new closure with each dependency at the version the new root records and removes dependency versions no install records any more). A dependency is never compared or reported, assets from a library's world belong to that library's unit, and a pulled row no table marks as a root is not reported. The second value lists `{ name, reason }` for the units whose origin could not be reached. Opening a world in an editor raises one notice with the same list. `world.pullAsset` aimed at a dependency of an install answers `<path> is a dependency of the install <name> (<root path>); update the root`. - `world.reviewUpdate(unit: string, opts: ReviewUpdateOpts?) -> UpdateReview` — what updating one unit changes, writing nothing: `from` (what the world holds) and `to` (what the origin holds at `opts.ref`, default the ref `world.checkUpdates` compares it with), then `commits`, the commits of the origin world in between, newest first, each `{ id, message, author, date }` (`more` is true past 200), then the files; `modified` names up front each file holding uncommitted changes (a dirty or staged row) that the update touches, with `merges` or `conflicts`. An installed asset (its root path; a path inside the install stands for the root) lists the commits that change the install back to the one that moved the root from the installed version, and `files`: each file the update adds, changes or removes, `{ path, change, diff, hunks, local_edit }`, `local_edit` being `none`, `merges` or `conflicts` for a file the world edited since it was installed. A library (`@<name>`, the `@` optional) lists its commits from the pin to the new commit and counts the library files that change and the world's files whose references move with the pin; `opts.files = true` adds `files` and `moving`, the lists behind the counts; the moving files are read from the engine's reverse reference index. `opts.commits = false` reads no commits and `opts.files = false` leaves an install's `files` and diffs out, so `{ commits = false, files = false }` is the check before an update: `modified` and the counts alone. A file listed in status only because its reference table moved (`references moved`, `install recorded`) holds no change of its own and is never in `modified`. An install's commit list stops at the commit whose parent holds the root at the version the install recorded, read from the root's closure at that commit, the root alone (`zeromind.world` op `closure`, `maxDepth = 0`), or at the commit that adds the root's path; when a version cannot be read the list stops there, `more` is true and `commits_error` says why. The origin's log, commits and diffs are read through the trusted ZeroMind bridge (`zeromind.world` ops `commits`, `commit`, `diff`). - `world.pull(branch: string?, opts: PullOpts?) -> PullResult` — `git pull`: fetch `origin/<branch>` (default the session branch) and merge it into the session branch: a fast-forward when the session branch is strictly behind, else a two-parent merge commit with markers on conflict; nothing when the session branch already holds the fetched commit, read before anything moves so a tree with uncommitted changes is not refused for it: for the session branch's own upstream the fetch's `behind` count answers that, for another branch the session branch's history does. `opts.ffOnly` refuses anything but a fast-forward, `opts.noFf` always makes a merge commit. - `world.update(units: (string | { string })?, opts: UpdateOpts?) -> UpdateResult` — apply updates: no `units` updates every unit `world.checkUpdates` lists, a name or a list of names (library names and install root paths, mixed) updates those, to `opts.ref` when given. A library moves its pin (`world.updateLibrary`), an installed asset pulls its new closure (`world.pullAsset`), one unit at a time; a unit that fails is reported in its entry with the reason and the rest still run. An install's pull refuses while a row it writes is conflicted (a row under its root, or the row a closure entry lands in), and runs over conflicts in every other row. Nothing is staged, committed or pushed: the updated files wait in `world.status()`. Returns `{ results, to_commit, skipped, warnings, note }`: one `{ unit, kind, from, to, ok, error?, merged?, conflicted?, added?, pruned?, moving? }` per unit, every path the updates changed or moved, the units the check could not read, one `{ unit, path, outcome = "merged" | "conflicted" }` per file holding uncommitted changes that an update touched, and a note that nothing was committed. - `world.uninstallLibrary(name: string) -> string` — delete the library marker file. - `world.installAsset(opts: InstallAssetOpts) -> InstallAssetResult` — imperative content pull from another world. - `world.assetInstallable(opts: AssetInstallableOpts) -> AssetInstallableReport` — whether one published asset resolves a closure of its own, as a verdict. - `world.installedAssets() -> { InstalledAsset }` — every asset this world carries from ZeroMind, keyed by the published guid it was pulled from. Types: - `WorldNamespace = { [string]: any }` — target table for `installInto`. - `LogOpts = { limit: number? }` - `CommitRow = { commit_id: string, parent_commit_id: string?, hivemind_pushed: boolean?, message: string?, created_at: number? }` - `StatusEntry = { path: string, dirtied_by: string?, dirtied_by_caller: string?, writer: string?, dirty_since_micros: number?, staged_action: string? }`: `dirtied_by` is the identity the row was written under, which every session of one account shares; `dirtied_by_caller` is the caller key of the call that wrote it (`client:<session>` / `actor:<sub>`, and `client:<session>@<engine seat>` for an agent an engine hosts in its dock, whose session id every engine repeats; a row keyed by a bare `client:ide-slot-<n>`, written before those keys named the seat, resolves to no agent); `writer` is what the row is to the calling caller (see `StatusResult`). - `StatusResult = { dirty: { StatusEntry }, staged: { StatusEntry }, untracked: { StatusEntry }, local_identity: string?, local_caller: string? }`: `local_identity` is this connection's identity and `local_caller` the calling caller's own key. `writer` is `"you"`, `"other"` (a caller whose session is open), `"ended"` (a caller whose session has ended) or `"unattributed"`; `dirtied_by_account` is the account a row's writer acts for and `same_account` whether that is the calling caller's; `local_account` is the calling connection's account. `claimed_by_other_stages` lists `{ path, stage_name, stage_row_id, owner_identity, owner_account, same_account, live, session, staged_action }` for each path another staging area holds; a staging call that stages one of them takes it out of that area. `writer_accounts_refusal` is set when the world's backend module predates the record of writers' accounts. - `ShowResult = { commit: any, parent: string?, entries: { any }, diff: any? }` - `DiffFile = { path: string?, action: string?, is_text: boolean?, added: number?, removed: number?, hunks: { any }? }` - `TrashRow = { row_id: number, op_kind: string?, path: string?, destroyed_by: string?, days_left: number? }` - `StashRow = { row_id: number, branch: string?, label: string?, author_hex: string?, created_at_micros: number?, dirty_count: number?, staged_count: number? }` - `StashSnapshot = { dirty: { any }, staged: { any } }` - `WorldEntry = { guid: string?, name: string?, title: string?, visibility: string?, role: string? }` - `InstallLibraryOpts = { world: string, commit: string?, as: string?, ref: string? }` - `InstallLibraryResult = { name: string, path: string, world_guid: string, version: string }` - `InstallAssetOpts = { guid: string, at: string?, ref: string? }` - `InstallAssetDep = { path: string, guid: string, version: string? }` - `InstallAssetResult = { assets_written: number, blobs_downloaded: number, root_guid: string, root_path: string?, root_version: string?, deps: { InstallAssetDep }, pending: { string } }`: `blobs_downloaded` counts the blobs the install fetched, and `pending` lists written paths that did not read back before the install's wait for them stalled ## Usage ```luau -- The prelude installs the wrapper at boot: require("@builtin::modules.world_vcs").installInto(world) -- After install, callers use the grafted methods on `world.*`: world.add("/source/foo.luau") world.add_all() local commitId = world.commit("feat: ship widget") local zmId, verdict = world.push() local s = world.vcsStatus() for _, e in ipairs(s.dirty) do print(e.path) end local commits = world.log({ limit = 20 }) local r = world.show("--stat", commits[1].commit_id) ``` ## Notes - One implicit "default" stage per (world, branch, user). `world.add` / `world.add_all` / `world.unstage` open-or-resume that stage idempotently. `world.commit` auto-closes on success. `world.discard` drops it without committing. - `world.add` is asset-aware: staging a path inside a composite asset (`.scene`, `.component`, `.bundle`, etc.) expands to the full asset family so the resulting commit's tree-hash stays consistent. - Commit ids are caller-allocated ULIDs generated client-side (Crockford base32, 48 bits ms timestamp + 80 bits randomness via `math.random()`). Not a cryptographic primitive — sufficient for client-side collision avoidance. - All `__spacetime_vcs.*` calls go through the same promise-await pipeline; `ERR:...` payloads are unwrapped into Luau errors. - `world.stashDrop`, `world.reset` and `world.deleteBranch` run through the destructive-affirm token mechanism, minted and affirmed in the same call. - `world.diff` and `world.show` mirror their git CLI counterparts' argument grammar, including `--stat`, `--name-only`, `--staged`, `--`, and `commit:/path`.

# discovery Content search in this engine. One question — `discovery.search { q, assetType, match, mode, limit }` — answered in one shape, in one of two modes. `match` belongs to keyword mode. **Keyword** reads the files each asset type's `type.yaml` names under `indexing.data` for the slot `match` selects: `identity` is the identity role (a README, usually); `capability` is the capability, interface and implementation roles together (code, guide bodies); `any` is either and `all` is both. It matches the query's words against those files verbatim and each hit says which role and file matched. It runs on this engine's own files, so unpushed content and a private world's own content are in it. **Semantic** is ZeroMind's ranking over what ZeroMind may embed: the builtin library, the origin worlds of installed libraries and imported assets, and this world itself when it is public. Say what you need in `q`, in plain words. The search decides which asset types the words are about, and a judge reads every candidate against the query; the hits it keeps come back best first. `match` does not apply to it. Leave `assetType` out: naming one replaces the search's own choice of types, so only the named types are searched and a type guessed wrong answers nothing even when the library holds what you asked for. Name a type only when the task fixes it. A private world's own content is out of its reach, and the answer's note says what it searched and that keyword mode searches the world's own files. The two modes never fall back to each other; the answer names the other one when it cannot answer. **The library corpus.** `library = true` asks the semantic ranking over the whole published library instead of the content this engine can reach (`discovery.libraryScope()` names no world, so the request carries no world filter). Each hit carries `local_` when this world already holds it. The same question is then asked of this world's own content by keyword mode (`keyword { own = true }`, which reads only assets `discovery.worldOwn` holds to be this world's: not the builtin library, not an installed library, not a dependency, not anything `world.installedAssets()` lists), and those matches are appended after the library's hits (`discovery.withWorldMatches`): a hit the library already returned stays where the library put it, every other one is listed after, marked `from = "world"`. The library's hits keep the order the search core gave them; no score is changed or combined. When ZeroMind cannot be asked (`resting`, `unavailable`), the world's own matches still answer and the note says the library was not searched and why. An engine bound to no world answers as before. Keyword mode refuses `library`. `discovery.searchGuides` asks the same question the way a `guides { query }` call does: the documentation types `DOC_TYPES` names, `guide`, `agentskill` and `assettype`. `discovery.searchTools` asks it the way a `search_tools { query }` call does: the types `TOOL_TYPES` names, `tool`, `toolbox` and `workflow`. Three surfaces mean three things (`guides` is the docs, `search_tools` is what an agent runs, `discovery.search` is the content), so a `guides` query answers out of the docs alone, and an answer holding no hit carries `NO_DOCS_NOTE`, which names `discovery.search` as the surface that reads modules, components, render features, shaders and the rest. Both MCP tools ask with `library = true` whenever the engine is bound to a world. Naming no `assetType`, keyword mode walks `discovery.guideTypes()` — the types `discovery.types()` lists that `DOC_TYPES` names — and semantic mode asks ZeroMind over them (`discovery.semanticKinds`, each type by the guid of its `.assetType`) for `SEMANTIC_FETCH_MAX` hits (100, the most one call answers) and keeps the first `limit` of those kinds (`discovery.onlyKinds`). Naming an `assetType`, it searches exactly those types; a list naming `tool`, `toolbox` or `workflow` is refused with a sentence that points to `search_tools`, and one naming any other type `discovery.types()` lists with a sentence that points to `discovery.search`. `searchTools` refuses a documentation type by pointing to `guides`, and a content type by pointing to `discovery.search`. The hits stay in the search's own rank order. ## The answer ``` { mode: "keyword" | "semantic", -- the mode that ran; absent on a refusal match: "identity" | "capability" | "any" | "all", -- keyword answers only from: "bound" | "library", -- the scope that ran status: "answered" | "private_world" | "resting" | "unavailable" | "refused", results: { { q, hits } }, -- one entry per query, in the order asked world: { guid, title, private }, -- the world this ran from, when one is bound searched: { { guid, title, why } }, -- the worlds it covered note: string, -- the reach this answer had, and where else to look scanned: number, -- keyword: the most assets one query read cut: boolean, -- keyword: whether a walk stopped at KEYWORD_SCAN_MAX } ``` `private` is stated once the world's visibility has been read. Semantic mode reads it — through `discovery.visibility`, which asks ZeroMind once per world and holds the answer — because it decides what ZeroMind is asked over. A keyword answer and a refusal ask ZeroMind nothing: they name the world from what the engine holds (`discovery.worldHere()`), so an unreachable backend never delays them. `private_world` is the status of an answered semantic search from a private world; a `resting` or `unavailable` one keeps that status and its `retry_in_s` or `error`. `note` is what an answered search says about its own reach. `PRIVATE_WORLD_NOTE` is what a private world's semantic search covered and which mode reads that world's own files; `ALL_KINDS_NOTE` is the semantic search that named no kind, so ZeroMind ranked over every kind it holds and a row can be of any of them; `NO_DOCS_NOTE` is the `guides` query the documentation held nothing for, and names the surface that searches every other kind. They stand in the one `note` when more than one applies, the private-world sentence first — `status` reads `private_world` there, so the sentence that status names opens what the answer carries. `why` is `builtin`, `this world`, `library` or `import`. A semantic answer's `searched` is the scope ZeroMind was asked over; a keyword answer's is the corpus it actually read — the builtin library when builtin assets were in it, this world when the world's own were. A `library` or `import` entry's `title` is read from the install record that brought its guid into this world; an install whose record carries none names that origin by guid alone. A hit carries `guid`, `assetType` (the server's wire field `kind`, renamed where a hit is read), `name`, `summary` — the first line of the asset's README that is neither blank nor a heading — and `local_`, the form of the asset this engine holds: `path`, plus `tool` for a tool (the identity a call names, from the tool registry through `tools.callable`), `toolbox` for a tool and for a toolbox (the name a drill-in lists the toolbox by), or `guide` for a guide or an assetType (the identity `guides { path }` reads), `workflow` for a workflow (the identity `workflow.start` runs), `skill` for an agent skill (the identity `agent_skill` opens), and `readme`, the VFS path of the asset's README when it holds one. A tool or toolbox hit also carries `local_.registered`, which says whether the registry holds what the hit names: the function a call to the tool would run (`tools.callable`), or the toolbox a drill-in would list (`tools.registeredToolbox`). A `.tool` folder whose source registered none has `tool = nil` and `registered = false`; a toolbox folder the registry holds nothing for keeps its `toolbox` name and has `registered = false`. `discovery.identityOf(hit)` is the one name the surface acting on a tool-family hit takes: a tool's `<toolbox>.<tool>`, a toolbox's drill-in name. A hit from keyword mode carries `matched = { role, file, terms, words, together }`: the role and file that carried the query's words best, how many of those words the asset carried anywhere in its text, how many it carried as words of their own, and the most it carried side by side in the query's order. A hit from semantic mode carries `score`, ZeroMind's own rank for it, and what the search core stated: `p` (the judge's probability, which is the order of a library answer), `type_key` and `system_key` (keys into the result's `types` and `systems`, which a library result carries beside its hits), `owning_world`, and `preview_description` when the server sends one. A semantic request names its types through `discovery.kindParam`: every registered type by the guid of its `.assetType`, builtin types included, which is the identity ZeroMind files a type under. A name no registered type answers to travels as written, so ZeroMind can say which name it does not know. `discovery.semanticKinds(names)` spells the ones of `names` that resolve. A search that names no kind where its surface documents some — none of them resolving — answers with `ALL_KINDS_NOTE`, so a caller reads the ranking's reach off the answer rather than off the rows. `discovery.shape(answer, "guides", query)` lists a guide or assetType hit with its `assetType`, the `path` `guides { path }` reads and its `summary`; a hit of any other type with its `assetType`, `name`, a one-line `purpose` and `vfs_path`, the README `read_file` opens. `discovery.shape(answer, "tools")` lists each hit with its `assetType` (tool, toolbox or workflow), its `identity` (`discovery.identityOf`), its `toolbox`, a one-line `purpose` and `registered`; a tool row also carries `tool`, the `use_tool` identity while the registry holds it and empty while it does not. Every row of both forms carries `guid`, `installed` (whether this world holds it), `use` (`discovery.nextCall`: the one call that acts on it, `use_tool { toolbox, tool }`, `search_tools { toolbox }`, the `workflow` toolbox's `start`, `guides { path }`, `agent_skill { name }` or `read_file { path }` for a hit this world holds, `zeromind_install { guid }` for one it does not), `p` when the search core judged it, and `from = "world"` on a match from this world's own content. ## Ranking Hits fall by `matched.weight`, what the query's words the asset carried as words of their own weigh together: `hand` in "hand it over" and `spawn` in "spawns" or "spawning" count, `off` inside "offline" does not (`matched.words` is how many of them there were). A word weighs `ln((read + 1) / (carriers + 0.5))`, where `read` is how many assets the walk read and `carriers` how many of them carry the word, so a word few assets carry outweighs several that nearly every asset carries: in "roster who is here" the tool saying "roster" ranks above the hundreds saying "who is here". Then by `matched.together`, the most of the query's words the asset carried side by side in the query's order (separated by spaces or hyphens), so "hand off" ranks above "hand" and "off" apart. Then by `matched.terms`, how many of the words the asset carried anywhere in its text, inside longer words included. Each word counts once however many of the asset's files carry it. Then by the order the type declares the role that matched in its `indexing.data`, then by name. `match: "all"` keeps only assets whose identity files and whose capability files each carried at least one of the words. A keyword answer's `results[i].total` is how many assets matched that query, of which `hits` are the best `limit`. ## The frames a search takes A keyword walk reads the files of up to `KEYWORD_SCAN_MAX` assets, which on a cold cache is thousands of reads. Called from code that can yield (a task, an `execute`, the engine shell, `search_tools`), it gives the frame back every `SLICE_MS` (8 ms) of reading, so the engine keeps stepping and drawing while it searches. `discovery.newSlice()` is that rule as a function, for any other walk to call between its pieces. Called from code that cannot yield, the walk reads everything within the one call. ## What it reads, what it holds, and what it reads twice A keyword query reads the files the recipe names for every asset of every type it covers. One copy of each file is kept — lowercased, which is what the match reads, plus the one line a README answers for — against the checksum the asset index reports for its asset (`asset.meta(ref).checksum`, the tree hash over the asset's own files). So a second identical query reads nothing, and an asset whose bytes changed is read again on the next query that reaches it. What is held is bounded by `TEXT_BUDGET_BYTES`, **16 MiB**; past it the least recently read asset's text is dropped, and a query that reaches it again reads it again. `discovery.stats()` reports `reads`, the number of `vfs.read` calls the module has made, and `bytes`, what it is holding right now. `discovery.forget()` drops all of it. Past the budget, the least recently read text is dropped until `TEXT_KEEP_FRACTION` (three quarters) of it is held, so the ordering that picks what goes is paid once per pass rather than once per read. ## How much one query reads A keyword query reads at most `KEYWORD_SCAN_MAX` assets, **500**. The walk takes this world's own assets first and the library's after them, since no other search answers for what the world holds; within each, it takes the types' assets in turn — the first of each type, then the second of each — so a bound walk samples every type instead of reading the first few types whole. A `tools.search` drilled into a toolbox (`{ toolbox = ... }`) walks the tools under that toolbox's folder and no others (`within`). The answer states `scanned`, how many it read, and `cut`, whether the types held more. The bound holds whatever the query names: `assetType` narrows which assets the 500 are, so a type holding more than 500 is cut too. `search_tools` asks for `tool,toolbox` (440 builtin assets), which fits inside the bound on the builtin library. A `guides` query that names no `assetType` covers `guideTypes()` — `guide` and `assettype`, 125 builtin assets — so its walk reads both types whole. A name no registered type answers to is refused, naming it and the types that surface reads, and so is a name whose type declares no indexing recipe, since no search reads its assets; `discovery.types()` is the whole list a `discovery.search` can read. Measured on a native headless offline engine, `dev` profile (optimized + debuginfo), Windows, `--dev` over the checkout, 2026-09-14. "Cold" follows `discovery.forget()`; "warm" repeats the same query. Every row but the fresh-engine one ran on an engine whose earlier walks had already read the same files once, so its cold figure is the module's cost without the first read of each file from disk. The builtin library holds 2,172 assets across the 42 types that declare a recipe and more than 46 MB of lowercased text; `module` (15.6 MB) and `testSuite` (past the 16 MiB budget on its own) are the largest. | Query | Assets read | Cold | Warm | |---|---|---|---| | builtin, no `assetType`, no bound | 2,172 | 28,558 ms, 6,051 reads | 19,309 ms, 6,002 reads (the text passes the budget, so it is read again) | | builtin, no `assetType`, bound 500, first query of a fresh engine | 500, cut | 8,328 ms, 1,283 reads | 159 ms, 0 reads | | builtin, `tool,toolbox` | 440 | 383 ms, 1,224 reads | 38 ms, 0 reads | | builtin, `guide,assettype` | 125 | 541 ms, 348 reads | 11 ms, 0 reads | | builtin, `searchGuides` naming `guide`, after `forget()` | 76 | 436 ms, 152 reads | 34 ms, 0 reads | | builtin + 1,500 world guides, no `assetType` | 500, cut | 8,320 ms, 1,192 reads | 136 ms, 0 reads | | builtin + 1,500 world guides, `guide` | 500 of 1,576, cut | 607 ms, 1,000 reads | 27 ms, 0 reads | The world guides were authored into the session's `/source` with `asset.create("guide", name)`, each carrying a two-line `README.md` and `guide.md`. What a read costs depends on the file: a guide's two small files read in 0.6 to 1.6 ms each, while an `animation`, `font` or `texture` asset's recipe files cost 17 to 42 ms each, which is why the bounded unfiltered walk — which reaches every type — costs more per asset than a family walk.

# modules.trusted User-space client for the **trusted → user call bridge**. Lets scene / library / code-mode scripts *trigger* orchestration that lives in the engine's trusted VM — auth, connection, and service flows we author in trusted Luau — without exposing the trusted source or the privileged primitives those flows use (`auth.*`, egress credentials, …). Auto-injected by the prelude as the global `trusted`, so scripts just call: ```lua local who = trusted.call("session.whoami") -- { linked = true, issuer = "https://…" } ``` `trusted.call(name, ...)` marshals the args into the trusted VM, runs the named handler against its `__TRUSTED_EXPORTS` registry, and marshals the single return value back as plain data (nil / boolean / number / string / table). It raises a Luau error if the method is not registered, the trusted VM is not ready, or the trusted handler errors. The handler must not yield. On the engine VM it runs **synchronously** in the call's frame. On a worker VM the call is queued for the engine thread, which runs the handler in the trusted VM; the calling task waits until the answer arrives and the call then returns it, so the call site reads the same. Backed by the single generic `__trustedBridge.invoke` Rust transport (`__trustedBridge.invokeQueued` on a worker VM, `crates/zero_scripting/src/ffi/bindings/trusted_bridge.rs`). Trusted methods are registered on the other side via the trusted module `/zero/trusted/exports` (`expose(name, handler)`). See `docs/specs/trusted-user-bridge.md` for the full design and the steps to add a new method (no Rust required).

# luau_introspect (module) Parses Luau/asset source TEXT into structured declarations. Pure string/pattern parsing (`string.find` / `string.match` / `string.gmatch`) over the literal source — no compiling, no VM spawn, no runtime state, no engine FFI. Given source text, it extracts what is written in the file. This is the shared parser every per-assetType `M.ref.inspect` hook uses to turn a component/module/tool's own source into the structured record `asset.inspect` returns. ## Exports - `docstrings(src) -> DocMap` — scans `--!desc` / `--!arg` / `--!return` / `--!example` comment runs and binds each run to the name of the declaration on the next non-comment line (the identifier after `function`, `public:`, `local function`, or `M.`). - `publicFields(src) -> { FieldEntry }` — parses `public = { name = Field.<kind>(default, mode), ... }` table-literal entries and module-scope `public.<name> = Field.<kind>(...)` assignments. - `events(src) -> { EventEntry }` — parses `events = { name = Event(payloadSchema?, syncMode?), ... }` table-literal entries. - `methods(src) -> { MethodEntry }` — parses `function public:<name>(...)` / `typed function public:<name>(...)` declarations (params + optional return type). - `lifecycleHooks(src, catalog) -> { string }` — top-level `function <name>(` declarations whose name is in the caller-supplied `catalog` array. - `moduleExports(src) -> { ExportEntry }` — parses `M.<name> = function` assignments, `function M.<name>(...)` declarations, and a trailing `return { foo = foo, ... }` export table. - `forSource(src, computeFn) -> any` — memoises `computeFn(src)` keyed on `src` itself in a module-local table. The same source text returns the cached result without re-running `computeFn`; different source text recomputes. Keyed on the source content (not an asset checksum) because composite/container assets (component folders, scene folders, etc.) all hash to the empty-string checksum — a checksum-keyed cache collapses every such asset's detail onto whichever one was inspected first. ## Usage ```luau local Introspect = require("modules.luau_introspect") local src = self:getInitScript() local detail = Introspect.forSource(src, function(s) return { fields = Introspect.publicFields(s), events = Introspect.events(s), methods = Introspect.methods(s), hooks = Introspect.lifecycleHooks(s, lifecycleCatalog), } end) ``` ## Notes - Every function is a pure string→table transform: same source text in, same structured table out, every time. No reads of live component state, no entity/world queries. - Structural scanning runs over a comment- and string-aware **mask** of the source (a same-length copy where comment bodies and string-literal contents are blanked to spaces, delimiters and newlines preserved). Pattern matches and brace/paren balancing run on the mask — so a brace, `Field.`, `Event(`, or a whole entry that appears inside a comment or a string literal never registers — while captured values are sliced from the original source at the same (aligned) indices. This makes the parser robust to apostrophes in comments, commented-out entries, string defaults containing `}` / `Field.` / `Event(`, and `[[ ]]` long strings. - `default` / `category` are raw trimmed source-text slices (with any trailing comment stripped), not evaluated values. - For a **ref constructor** (`Field.assetRef` / `dataRef` / `resource` / `componentRef`) the FIRST positional argument is the category / contract / componentType selector, captured under `category`; the SECOND argument is captured under `default`. - For every **other** Field kind the first argument is the `default` and `category` is nil. - A trailing `Sync` / `NoSync` identifier is captured as `sync`, tolerating a trailing comma or a trailing comment after the last argument. - Field/Event entries whose key is a computed or indirect expression (`[expr] = Field.number(...)`) are omitted — only literal identifier keys are recognised. - `methods` captures a `...` variadic parameter (as `name = "..."`), with its `: <type>` annotation when present. - A `--!desc` written above a field/event declaration (`<name> = Field.<kind>(...)` / `<name> = Event(...)`) or a `public.<name> =` assignment binds to that name in `docstrings`, and is folded into the corresponding `publicFields` / `events` entry's `desc`. - `lifecycleHooks` never hardcodes the lifecycle-callback catalog; the caller passes the list of names to match against. - `forSource`'s memo is bounded (oldest-key eviction) so a long session touching many distinct asset versions can't grow it without limit.

# ik Look at a rig's bones and at what an IK solve is actually doing. Debugging IK means answering three questions, and none of them can be answered from a screenshot: what are this rig's bones called, where are they right now, and is the chain reaching its target or merely near it. `bones` lists a body's bones with their world positions and parents — the names you need before naming a chain, and the positions you measure against when checking a solve from outside the component. Rigs rarely use the word you would guess: the standard humanoid here calls its feet `Ankle_L` and `Ankle_R`, with no bone containing "foot" anywhere. `reach` reports how far a limb can extend and how far away a point is, both in the same units. A target beyond a limb's reach has no solution — the chain extends straight toward it and stops, which is correct and looks exactly like a broken solver. This is the first thing to check when a solve looks inert. `state` gathers every IK component on an entity and reports what each one is doing, so "is anything solving at all" is one call rather than five.

# assetType runtime The machinery that reads a `<typename>.assetType/behavior.luau` and turns its declarations into live behaviour. A `behavior.luau` is a table of declarations — `ref` methods, `modules` shared code, an `events` schema, a `namePattern`, `refShapes`, and the `onCreate` / `onRegister` / `onChange` / `onDelete` / `validate` / `settingsDefaults` / `settingsCorrections` hooks. None of it runs itself. This is the code that runs it, and it lives here because reading a type's declarations is the **assetType type's own behaviour** — the same way `material.assetType` owns what a `.material` does. ## Sub-modules | Module | Reads | Responsibility | |---|---|---| | `ref.module` | `ref`, `modules` | Builds every `AssetRef` envelope, attaches the shared metatable, and dispatches per-type methods and shared modules onto it. Also owns edit-mode write-behind persistence. | | `create.module` | `onCreate`, `namePattern`, `validate` | Backs `asset.create`: resolves the type, checks the name against its pattern, runs `onCreate` (or clones `template/`), and writes the instance. `validate.module` beside it checks a creation `opts` table against the type's `createSchema`. Before running `onCreate`, resolves the type's settings chain (below) and hands the result to the hook as `opts.settings`. | | `settings.module` | `settings`, `settingsDefaults`, `settingsCorrections` | A type's declared settings schema and where its values live (`type.yaml`'s `settings:` block). `Settings.resolveForCreate` layers the schema's own defaults, the type's own `settingsDefaults(name, opts, asked)` hook (a DEFAULT the schema can't express — a name-derived convention, a fact read off a payload the caller handed it, a value following a field `asked` shows a higher layer naming; any later layer overrides it), the Preset Manager, an importer's settings, the caller's `settings` table, then the type's own `settingsCorrections(values, name, opts)` hook (a CROSS-FIELD CONSTRAINT the schema can't express, applied last over the fully merged values). A correction over a default/preset/importer value lands silently; a correction that would override what the caller's own `settings` table explicitly asked for refuses the creation instead, naming the field and why. Neither hook is ever handed a table to mutate; each returns what it wants changed (`settingsCorrections` may also return a `{ [field]: reason }` table for that refusal message). `Settings.cloneValues` deep-copies a values table — `create.module` hands `onCreate` a copy, never the table it stamps. `Settings.valuesOf` / `writeValues` read and write an asset's own values file. | | `typeYaml.module` | `type.yaml` | The folder a type lives in and its parsed `type.yaml`, decoded once per content version of the file. `settings.module` and `inspector.module` read their blocks through it. `about` / `aboutAt` read a type's `about.yaml` (`intent`, `function`, `usage`), leaving out any key that is empty or still starts with `[[describe]]`; `aboutRows` and `aboutMarkdown` lay the texts out for the Inspector and the `types/<name>` guide. | | `inspector.module` | `type.yaml`'s `inspector:` block | Which inspector a type declares for its assets (`inspector: { type: ... }` or `{ instance: ... }`), and the declaration that file returns — the sections it adds, the generic ones it replaces, and their order — or the problem that kept it from loading. | | `onRegister.module` | `onRegister` | Fires an instance's once-only registration hook — on arrival, on world load, and for `@builtin` library instances. | | `changeDispatch.module` | `onChange`, `onDelete`, `refShapes` | Routes a VFS source write or a folder delete to the enclosing typed asset's type hooks. | | `refShapes.module` | `refShapes`, `ref` | Publishes what every `AssetRef<category>` answers to, so a member read on an asset-typed value is checked against that category's real surface. | | `events.module` | `events` | The per-asset event runtime behind `ref.events`. | | `instantiable.module` | `ref.instantiate` | The instantiation contract an asset type opts into: `root` stands the root entity, `place` applies the base placement opts to one the type adopted, and `result` shapes the `(root, idMap)` every `instantiate` returns. Also registers the `sceneInstantiable` field-constraint validator. | | `declaration.module` | `type.yaml` | The type's decoded declaration, read once and held until a write inside an `.assetType` folder; what every question about a type as a whole reads. | | `previewRecipe.module` | `type.yaml` `preview:` | How an instance's `preview.png` is produced: which of the four recipes (`instantiate`, `image`, `surface`, `custom`) the type declares, and what that recipe needs. | ## Reaching it ```luau local rt = require("@builtin::assetTypes.assetType.shared") rt.ref.loadTypeBehavior("material") ``` Fields resolve lazily. The prelude requires the sub-modules directly, in dependency order (`ref`, then `changeDispatch`, `onRegister.install()`, `refShapes.install()`) — a table that required all six on load would take that ordering away from it.