# zm.add
Stage paths for the next commit. Takes a single path or an array of paths and marks them ready to be committed, following git staging semantics: an array stages every row its paths select once, so several files of one asset stage that asset's family once. Passing `.` (or the `-A` / `--all` sentinels) stages every dirty path at once, the same shortcut the shell `zm add` builtin recognises. Staging is the step between editing the working copy and committing — a commit takes only what has been staged.
A scene is staged as its `scene.json` holds it. Pending live scene edits (entities spawned or changed through the ECS) stay pending: write them into the scene first with the `sceneAuthoring` toolbox (`changes`, then `acceptChanges`) or, in edit mode, `layers.active:save()`. When a stage leaves pending edits out, a notice names them and the calls that keep or drop them.
# zm.branch
Branches — `git branch`.
- `zm.branch()` lists the branches, the session's marked `current`; `{ remotes = true }` lists origin's (`origin/<name>`) and `{ all = true }` both.
- `zm.branch("feature")` creates `feature` at `HEAD` (`{ start = "<rev>" }` starts it elsewhere). The session stays where it is; `zm.checkout("feature")` moves it, bringing your uncommitted changes along.
- `zm.branch("feature", { delete = true })` deletes it. It refuses a branch whose commits the session's branch does not hold, or whose working tree holds uncommitted changes; `{ delete = true, force = true }` deletes it regardless (`git branch -D`).
- `zm.branch("feature", { rename = "feature-2" })` renames it.
A name starting with `-` is refused: it is an option in git, never a branch.
# zm.checkout
`git checkout`.
- `zm.checkout("feature")` switches this session to `feature`. Your uncommitted changes and staged entries come with you; a switch that would replace a path you changed with a different version refuses with git's message naming the paths, and nothing moves — commit or `zm.stash` first. Another caller's uncommitted changes stay on the branch they were made on. Returns once the branch's content has landed.
- `zm.checkout("feature", { create = true })` creates `feature` at `HEAD` (or `start`) and switches to it.
- `zm.checkout("", { paths = { p }, theirs = true })` takes the merged-in side of an unmerged path whole (`ours` takes the session branch's); `zm.add(p)` then records the resolution.
- `zm.checkout("", { paths = { p }, rev = "HEAD~1" })` writes the path as that revision holds it, and stages it.
# zm.commit
Materialize the currently staged tree as a new commit with the given message, checkpointing the world's content. Following git semantics, it takes only what has already been staged and does not auto-stage dirty paths, so stage first. On success it returns the new commit id. A commit is a local checkpoint; publishing it to others is a separate push.
# zm.fetch
Update the `origin/<branch>` remote-tracking ref — `git fetch`.
Mirrors the world's ZeroMind branch head into local commit history without touching the working tree, and reports how the session branch relates to origin: `behind` counts origin commits you don't have, `ahead` counts local commits origin doesn't have, and `diverged` means both.
Content can advance on ZeroMind outside your session — a collaborator pushes, a pull request merges, an installed pin moves. Fetch is how that drift becomes visible: `zm.status` shows the remote-tracking line as of the last fetch, and `zm.pull()` reconciles (fast-forward when behind, three-way merge when diverged).
# zm.log
The history of a revision, newest first — `git log`.
Every commit reachable from `rev` (default `HEAD`) through both parents: a merged branch's commits and pulled commits appear along with the ones recorded on the branch. `{ limit = N }` caps the count (0, the default, returns them all), `{ rev = "feature" }` starts elsewhere, `{ path = "/source/foo.luau" }` keeps the commits that touched one file.
# zm.merge
Merge a branch into the session's branch — `git merge <source>`.
The merge runs locally in the world; nothing reaches ZeroMind until the result is pushed with `zm.push`. When the session's head is in the source's history the head fast-forwards onto it; otherwise a two-parent merge commit lands. `{ noFf = true }` always makes a merge commit and `{ ffOnly = true }` refuses anything but a fast-forward.
Local changes follow git's rule: one on a path the merge rewrites refuses the merge with git's `Your local changes ... would be overwritten by merge` message, naming the paths; every other local change stays in the working tree. A scene's unsaved live edits count as a local change to its `scene.json`: a fast-forward that rewrites that scene refuses, naming the scene and how to save or discard the edits, and a merge commit refuses over any scene holding them.
On conflicts, git-style markers are written into each conflicting text file and the cleanly-merged remainder is applied; `zm.status` lists the unmerged paths. Resolve each (edit out the markers, or take one side whole with `zm.checkout("", { paths = { p }, theirs = true })`), then `zm.add` + `zm.commit` — that commit records the merge. `zm.merge("", { abort = true })` aborts the merge in progress.
# zm.prConflicts
Read what stands between a pull request and a merge.
Returns the mergeability verdict, the merge base, both heads, and one entry per conflicting path. A conflicting TEXT path carries `marked_text`: the same `<<<<<<<` / `=======` / `>>>>>>>` rendering a merge leaves in a working tree, with the source and target sides laid against their common ancestor. A binary path carries the two sides' hashes and no text, so pick a side.
Resolve a path by writing the settled bytes back to it and committing on the source branch. The request re-analyses on the next read, so a resolved path stops appearing here.
A mergeable request returns an empty conflict list. `zm.prView` says HOW MANY conflicts there are; this says WHAT they are.
```
zm.prConflicts(nil, 1)
zm.prConflicts("11111111-2222-3333-4444-555555555555", 3)
```
# zm.prCreate
Send your changes to installed content upstream — `zm pr create`. For each origin world your installed content came from, the files you changed are three-way merged against the origin's current content (a region the origin changed too becomes a local conflict to resolve first), pushed as a branch in the origin world, and opened there as a pull request — merged straight away when you may merge there (`{ merge = false }` leaves it open).
`zm.prCreate()` sends every installed asset that is ahead of its upstream; `zm.prCreate({ "/source/Doom.component" })` sends the named install roots. `zm.status` lists what is ahead and `zm diff <root> upstream` shows the changes. `{ dryRun = true }` reports the plan without sending anything.
# zm.prList
List a world's pull requests, or fetch one by number.
Returns ZeroMind's response: `pulls`, each carrying who opened it, when, its state, and the two ends it joins — source world and branch, target world and branch. Pass a number to fetch a single request instead of the list.
Requests are listed on the world they **target**. A fork's outgoing requests appear on the upstream world, not on the fork, so list the world you proposed TO.
`zm.prView` re-analyses one request against the current branch heads and says what it changes; this says which requests exist.
```
zm.prList()
zm.prList("11111111-2222-3333-4444-555555555555")
```
# zm.prMerge
Merge a pull request — the agent-side merge button.
Lands the request's work on its target branch and closes it as merged, returning the merge commit and the diff it carried. `merge` (the default) records a merge commit; `squash` collapses the request to one commit; `fast_forward` moves the target head when nothing diverged.
A request whose paths conflict is refused rather than merged. `zm.prConflicts` says which paths and what the two sides hold; settle them on the source branch and the request re-analyses on the next read.
The world argument is the world the request lives in — the one it targets.
```
zm.prMerge("11111111-2222-3333-4444-555555555555", 3)
zm.prMerge(worldGuid, 3, "squash")
```
# zm.prOpen
Open a pull request — propose the work on one branch for merging into another.
Both ends are addressable, which is what lets a fork propose work back to the world it came from: pass `targetWorld` and the request is opened against that world, sourced from this one. With no target world the request stays inside the world you are in, which is the ordinary branch-to-branch case.
A pull request references **published** commits. Work sitting only in your session is not part of one, so `zm.push` first — otherwise the request proposes a commit the other end cannot see.
A request lives in, and is numbered by, the world it **targets**, exactly as a forge numbers pull requests on the upstream repository. So a fork's outgoing requests are listed on the world they were opened against, not on the fork.
```
zm.prOpen({ title = "fix the door hinge" })
zm.prOpen({ title = "port the fix", targetWorld = "11111111-2222-3333-4444-555555555555" })
```
# zm.prView
Read one pull request in full — `gh pr view`.
Returns the record plus a LIVE re-analysis against the current branch heads: the mergeability verdict (`clean` / `conflicts` / `fast_forwardable` / `up_to_date` / `unrelated`), how many paths conflict, and the diff — every path the request adds, modifies or deletes, with its checksums.
Read this before merging. It is what tells you WHAT the request changes; merging without it is merging blind. When it reports conflicts, `zm.prConflicts` says what they are.
```
zm.prView(nil, 1)
zm.prView("11111111-2222-3333-4444-555555555555", 3)
```
# zm.pull
`git pull`: fetch `origin/<branch>` and merge it into the session branch. With no branch it pulls the session branch's own origin branch.
- **Strictly behind**: the session branch fast-forwards to the fetched commit.
- **Diverged**: a two-parent merge commit lands, with the same conflict-marker flow as `zm.merge`. Resolve the markers, then `zm.add` + `zm.commit`; `zm.merge("", { abort = true })` abandons it.
- **Already contains it**: nothing changes.
- `{ ffOnly = true }` refuses anything but a fast-forward. `{ noFf = true }` always makes a merge commit.
A local change on a path the pull rewrites refuses it with git's message naming the paths; every other local change stays in the working tree. A scene's unsaved live edits count as a local change to its `scene.json`: a fast-forward that rewrites that scene refuses, naming the scene and how to save or discard the edits, and a merge commit refuses over any scene holding them. `zm.fetch` first shows what a pull would do.
Updating an installed asset or a library is not a pull. Use the `zeromind` toolbox for that: `zeromind.updates` lists what has updates, `zeromind.reviewUpdate` shows what one changes, and `zeromind.update` applies it without committing.
# zm.push
Publish unpushed commits to ZeroMind, making the world's content available to others. Like a git push, it walks the parent chain from the current commit and publishes the whole unpushed stack oldest-first, so no commit lands before its parent. It returns `{ commitId, verdict }`: `verdict` is `"published"` with the final published commit id in `commitId`, or `"already-published"` when the remote branch already carries every local commit — the state a push asks for, so it comes back as a result rather than a failure.
A push only moves the remote branch forward, as git's does: a remote head the branch does not hold is git's `! [rejected] <branch> -> <branch> (fetch first)` and one the branch is behind is `(non-fast-forward)`, so pull first. `force = true` is `git push --force`: a published head moves the remote branch regardless, which needs the Maintainer role on the world; a branch with unpublished commits is refused, so pull first.
A refused publish comes back as a failed result rather than aborting the caller, so the reason is inspectable: network errors, a parent that has not been pushed yet, access denials, sign-in problems (which name whether you were never signed in or your sign-in expired, and the recovery step — commits stay local and publish after re-auth). Authentication is read from the credential store; scripts never see the token.
# zm.reset
Move the session branch's head — `git reset [--soft|--mixed|--hard] <commit>`, in one shot (no confirmation step).
`target` is any revision `zm.revParse` reads, any commit of the world. `{ mode = "soft" }` keeps the index and the tree (the paths the move changed read as staged); `mixed`, the default, unstages and keeps the tree; `hard` unstages and takes the tree to `target`. `zm.reset("HEAD")` unstages everything and `zm.reset("HEAD", { mode = "hard" })` discards your local changes.
Reset is non-destructive for history: the commits the head leaves behind become trash entries, and `zm.trash("restore", <handle>)` re-attaches them in chain order (oldest first).
# zm.restore
`git restore`.
- `zm.restore(path)` takes the working edits on a path back to what it was staged or committed as: the stage where the path is staged, the last commit where it is not, and absence where it is neither. A folder takes every file beneath it back with it, and a deleted path comes back as its committed version. Edited bytes going back to a committed version are snapshotted to trash first (`zm.trash` lists them). `.` restores every path.
- `zm.restore(path, { source = "HEAD~1" })` takes the working content to that revision's version instead.
- `zm.restore(path, { staged = true })` unstages the path and leaves the working tree as it is; `{ staged = true, worktree = true }` does both.
Returns `{ restored, skipped, unstaged }`; a path with nothing to restore is listed under `skipped`.
# zm.revParse
`git rev-parse`: the commit a revision names. A revision is `HEAD`, a branch, `origin/<branch>` (as the last fetch recorded it), a commit id or a unique prefix of one, each optionally followed by `~N` (N first parents back), `^` (the first parent) or `^2` (a merge commit's second parent). `zm.revParse("HEAD")` is the head commit.
# 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.
# zm.stash
`git stash`: set your uncommitted changes aside and bring them back.
- `zm.stash()` (or `zm.stash("push", { message = "..." })`) saves your changed and staged paths into a stash and takes them back to their committed version. Content a stash records by checksum alone (binary or large files), and files no commit holds, stay in the working tree and are listed under `kept`.
- `zm.stash("list")` lists your stashes, newest first; `stash@{0}` is the newest.
- `zm.stash("pop")` applies the newest stash and drops it; `zm.stash("apply")` applies it and keeps it; `zm.stash("drop")` drops it (to trash). Each takes a stash as `stash@{n}` or a row id: `zm.stash("pop", "stash@{1}")`. Applying refuses, writing nothing, when a path the stash restores holds a different local change.
# zm.status
The active world's working state — the view the shell `zm status` prints, as a table.
Returns `world.vcsStatus()`'s `{ dirty, staged, untracked, unmerged, installs, ... }` with `branch` and `head` folded in, `blockers` (every reason a push by this caller would refuse, one entry per class with its subjects and remedy), and `upstream`: the installed content ahead of its upstream — the files you changed in an installed asset, grouped by the world it came from, each entry naming its install `root`. `zm diff <root> upstream` shows those changes and `zm.prCreate` sends them upstream.
`opts.stage` reports one of your own staging areas in place of the default one.
# zm.trash
The world's shared 7-day trash — what destructive operations threw away: commits a `zm.reset` left behind, working edits `zm.restore` replaced, dropped stashes, removed files.
- `zm.trash()` lists the entries; each `row_id` is its handle.
- `zm.trash("restore", handle)` recovers one. Commits a reset left behind re-attach in chain order, oldest first.
- `zm.trash("empty")` deletes every entry for good.
# 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`.
# 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.