effectcraft/AGENTS.md

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## House rules

These apply in every Craft repository. A later rule may be stricter, not weaker. The source is `standards/house-rules-core.md` in `storytold/craft-contrib`. Propose changes there, not in a copy.

1. **A person is accountable.** Whoever runs an agent answers for what it opens and for its review comments.
2. **Check, then claim.** Before writing code, read the issue comments, search pull requests for `#N` and the keywords, and check recent commits on `main`. Comment on the issue first. Release a claim you will not finish.
3. **Verify, don't guess.** Open a definition before using it. Confirm the cause in the code, even when someone names a location.
4. **Keep fixes narrow and tested.** Fix what the issue describes, where the bug is. Add a test that fails without the fix.
5. **Review the diff before opening a pull request.** Identifiers exist as used, the test fails without the fix, nothing unrelated changed, and the description is true.
6. **Look for a better pull request.** If another fixes the same thing, close yours when it is better or equal, and say why.
7. **Report only what ran.** Say what you tested and what you could not run. Without a local build or test, say so and rely on CI before marking ready.
8. **`main` changes through a pull request.** Do not push to it. Branch protection enforces this. There is no exception.
9. **Stop and ask only about** licensing outside the allowlist, publishing, releases, a new remote, secrets, spending money, destructive git, and anything else hard to undo. Otherwise keep working. `plan/` is a gitignored notebook, not rules. Without it, do not ask for it and do not stop.
10. **Keep secrets and personal details out** of the repository, logs and requests.
11. **CI stays shared.** Workflows call `storytold/craft-common-actions`. Do not change CI in a feature or fix pull request. If CI cannot cover a change, open an issue there.
12. **Guards say why.** A check that looks removable says what it prevents. Read that before changing it.
13. **Instructions must be readable by everyone.** No notes about one machine, and no links to files a reader cannot open. `craftrules` is retired. Do not link to it.
14. **Keep pull requests moving.** Concurrent pull requests are fine; unanswered actionable feedback is not. Respond in 7 days, a reminder at 14, closure eligible at 30, from when an actionable request waits on the author. Suggestions and unconfirmed bot findings do not start the clock. A fix, explanation or agreed plan resets it; unrelated activity does not. Waiting on a reviewer or maintainer pauses it and does not count against the author. A maintainer decides closure; it is never automatic. Reuse search results, do not poll, and stop at a rate limit.
15. **No agent attribution.** A pull request does not say an agent wrote it. A repository rule may not require that.
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## Rust Craft repositories

These apply to native Craft apps and to shared Rust libraries. Select them by repository type. A repository that merely contains some Rust does not take this block. Rules later in a repository's file may be stricter, but not weaker. The source is `standards/house-rules-rust.md` in [storytold/craft-contrib](https://github.com/storytold/craft-contrib).

1. **Never crash.** Non-test code does not panic and has no `unsafe`, except where the repository file names an exception. Return errors, treat input as hostile, and bound recursion and allocations. New production crate roots copy the `deny` attribute from an existing crate: `clippy::unwrap_used`, `clippy::expect_used`, `clippy::panic`, `clippy::unimplemented`, `clippy::todo`, `clippy::unreachable`. Every crash fix comes with a test that panicked before the fix.
2. **Clean room.** Learn from observed behaviour and public specifications. Do not copy another product's code, assets, strings or artwork. Check a dependency's licence before adding it.
3. **Assets and fonts.** Every asset is original or suitably licensed, and is recorded in `ATTRIBUTION.md` in the same change. Font files live in [storytold/craft-fonts](https://github.com/storytold/craft-fonts), not in the app repository.
4. **Rust only for native Craft apps.** No handwritten JavaScript or TypeScript, and no Tauri, Electron or webview shell, in those apps. Shared tooling follows its documented technical scope and maintainer-approved exceptions. Craft PR Review's existing Tauri and TypeScript UI is one such exception. It does not relax this rule for native apps. Preserve any existing web build.
5. **Time goes through `chrono`.** Do not hand-roll calendar conversion. For dates beyond what `chrono` can represent, follow [standards/time.md](https://github.com/storytold/craft-contrib/blob/main/standards/time.md).
6. **Contributor credits.** Add or edit only your own person's entry in `contributors/people.toml`, and only after asking them. Never guess a name or hand-edit `contributors.json`.

## Licence allowlist

Dependencies and assets use SPDX identifiers. An expression is allowed when every identifier is in this list. A repository may name a shorter list. It may not add an identifier here by editing its own copy of these rules.

- `ISC`
- `MIT`
- `BSD-2-Clause`
- `BSD-3-Clause`
- `Apache-2.0`
- `OFL-1.1`
- `Ubuntu-font-1.0`
- `Bitstream-Vera`
- `CC0-1.0`
- `CC-BY-4.0`
- `CC-BY-SA-4.0`
- `LicenseRef-Public-Domain`

`LicenseRef-Storyteller-Trademark` is not in this list. It covers Storyteller brand marks only, where a repository already says so.
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# EffectCraft — rules for agents and contributors

These rules apply to every human and AI contributor. `CLAUDE.md` holds the working instructions; this
file holds the rules that must never be broken. When the two disagree, this file wins.

## Never crash

People trust EffectCraft with hours of work. A malformed project, PSD, SVG, Lottie or media file, a bad
expression or script, a broken plug-in, a bad control-channel or MCP argument, a corrupt preferences file
or a full disk must produce an error the user (or agent) can act on, never a crash and never lost work.
**This rule outranks feature work:** don't ship a feature by adding a panic path, and fix a crash before
building on top of it.

- **Fail with `Result<T, E>`** through the crate's error type and propagate with `?`; add context
  (`map_err`, an error variant) rather than discarding it. Lenient readers fall back and record the repair.
- **No panicking shortcuts in non-test code:** no `unwrap()`, `expect()`, `panic!`, `unreachable!`,
  `todo!` or `unimplemented!`. Use `?`, `ok_or(..)?`, `let … else`, `if let`, or `unwrap_or*` where a
  fallback is genuinely correct (never where it would silently corrupt a document). Unfinished features
  return an "unsupported" error. The only exception is a provably infallible literal, written as
  `#[allow(clippy::expect_used)]` + `.expect("why this cannot fail")`.
- **No `unsafe`** (`unsafe_code = "forbid"` for the workspace).
- **Every input-derived number is hostile.** Use `get()` instead of `[i]`/`[a..b]` when the position
  comes from a file, a user, an agent or arithmetic on those; slice strings only at char boundaries; use
  checked or saturating arithmetic for lengths, offsets and counts; guard division by zero and NaN/inf
  casts; cap allocations sized by input.
- **Bound recursion:** projects, precomps, expressions and SVG/PSD trees can be cyclic or deeply nested;
  walk them with seen-sets or depth limits.
- **Don't cascade:** handle lock poisoning (`lock().unwrap_or_else(PoisonError::into_inner)` or an
  error), and treat worker-thread join results as `Result`s.
- **Last-resort guard:** the app wraps command execution and file import/export in a panic hook /
  `catch_unwind` boundary that turns an escaped panic into an error and keeps the document. It is a
  safety net, not a substitute for the rules above; keep `panic = "unwind"`.
- **Prove it:** every crash fix comes with a small synthetic regression test that panicked before the fix.

Tests, benches, fuzz targets and `xtask` may `unwrap()`; `clippy.toml` allows it in tests. Crates that are
clean carry `#![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented,
clippy::todo, clippy::unreachable)]`; new crates start with it.

## 1. Assets: no Adobe artwork, every asset licensed and attributed

This rule is absolute. Breaking it is the most serious mistake a contributor can make on this project.

**What counts as an asset:** any image, icon, cursor, logo, illustration, screenshot, font, colour LUT,
preset, template, sound, music, video, 3D model, or other non-code media. This covers files in the
repository, bytes embedded in code (`include_bytes!`, base64, data URIs), and data hard-coded to
reproduce an image (for example, point lists traced from someone else's icon).

1. **Never use Adobe iconography, images or other Adobe assets**, in any form:
   - no icons, cursors, logos, splash screens, UI artwork or screenshots from any Adobe product;
   - no Adobe fonts, LUTs, presets, templates, sound effects, stock media or sample projects;
   - no traced, redrawn, recoloured or "inspired-by" copies of Adobe icons. Our icons may follow generic
     conventions (a play triangle, a razor blade, a stopwatch), but each must be drawn from scratch
     without reference to Adobe's artwork.
2. **Every asset must be open**: open-source licensed (MIT, Apache-2.0, BSD, ISC, zlib, SIL OFL…),
   public domain / CC0, or Creative Commons (CC BY or CC BY-SA; no NC/ND licences), **or** created by a
   contributor who owns it and licenses it to the project under the project licence (MIT OR Apache-2.0).
   If the licence is unknown or unclear, the asset does not go in.
3. **Every asset needs an attribution sidecar.** Next to each asset file `X`, add `X.attribution` with:
   ```text
   asset:        <file name>
   title:        <what it is>
   author:       <creator / copyright holder>
   source:       <URL, or "original work" for contributor-made assets>
   license:      <SPDX id or licence name>
   license-file: <path to the licence text, if the licence requires shipping it>
   added:        <YYYY-MM-DD> by <contributor>
   notes:        <how it was made or modified; for screenshots, what is shown>
   ```
   Also add one line for the asset to [`ATTRIBUTION.md`](ATTRIBUTION.md). `cargo xtask assets` (part of
   `cargo xtask ci`) fails if any asset lacks a sidecar or index entry.
4. **Screenshots** in the repo may show only EffectCraft (or other open projects), with media we generated
   or media that is itself openly licensed. Never commit screenshots of Adobe products.
5. **Local reference material stays local.** After Effects reference screenshots and notes live only in
   `plan/aftereffects/` (gitignored). They must never be committed, bundled, embedded, traced or shipped.
6. **Code-drawn assets** (icons in `crates/ui-egui/src/icons.rs`, procedural demo content in
   `crates/engine/src/demo.rs`, generators in `crates/effects`) are original work under the project licence
   and are listed in `ATTRIBUTION.md`.
7. **When in doubt, leave it out** and draw or generate it yourself.
8. **The one exception: first-party ArtCraft brand marks.** The ArtCraft name and logos in `docs/brand/`
   are trademarks of the ArtCraft Team, not open source, usable only unmodified and only in the context of
   EffectCraft under `docs/brand/LICENSE-brand.txt` (forks and modified versions must remove them). They still
   need a sidecar and an `ATTRIBUTION.md` row (licence `LicenseRef-ArtCraft-Trademark`). No other
   non-open asset is allowed, and this exception never covers third-party marks (Adobe, Discord, GitHub
   and other logos stay out; draw a generic icon instead).

## 2. Clean-room code

- Never read, disassemble or copy anything inside Adobe application bundles; file names and listings only.
  Observe behaviour by using the app; never capture its Home screen, recent projects, account info or
  file browsers.
- Never copy GPL/LGPL/AGPL code (FFmpeg, Natron, Blender, Glaxnimate, Synfig, Friction, Olive, MLT, frei0r, G'MIC…).
- Never read or copy Adobe expression/scripting implementations, `.ffx` presets or effect plug-ins; the public Expression Language Reference and Scripting Guide describe *behaviour* only.
- Implement codecs and formats from public specifications (ITU-T/ISO/IEC standards, IETF RFCs, the VP9
  and AV1 bitstream specs, SMPTE documents, published container specs). Do not read the source of
  reference or third-party decoders/encoders while implementing a format, even permissively licensed
  ones (libvpx, libopus, libaom, dav1d, openh264…); spec text and conformance vectors only. Record the
  spec edition used in the crate README.
- ffmpeg/ffprobe may be used only as external test oracles and fixture generators. They are never
  linked, bundled or shipped.
- Dependencies must use permissive licences: MIT/Apache-2.0/BSD/ISC/Zlib/Unicode/CC0/BSL-1.0, or
  MPL-2.0 used unmodified.

## 3. Engineering rules

- **Layering** (`cargo xtask layers`): nothing below L5 depends on egui/eframe/winit/rfd/cpal; L0–L4 build for wasm32.
- **Exact time:** `effectcraft_time::Tick` (254 016 000 000/s). Keyframe times are layer time.
- **Property tree:** everything animatable is a `Property` in the layer's `PropGroup` tree, addressed by paths (`transform/position`, `effects/#1/blurriness`, `@uid`).
- **Everything is a command** (`crates/engine`): id, label, menu path, shortcut, params, enabled(), run(). UI, CLI, control channel and MCP dispatch by id.
- **Everything is agent-drivable:** every interactive widget registers an automation id; UI state is serde.
- **Community links** (Help menu, About, header Discord button): https://discord.gg/artcraft, https://getartcraft.com, https://getartcraft.com/apps/effectcraft, https://github.com/storytold/effectcraft.
- **Quality gates** before every commit: `cargo xtask ci` (fmt, clippy -D warnings, tests, layers, assets, wasm).
- New workspace crates include `[lints] workspace = true` in `Cargo.toml`. Production crate roots declare the crate-level lint attributes before modules; crate-level `//!` documentation may precede them.
- **Commits:** one task id per commit (`M6.3: trim paths`). Only green states.
- `cargo run -p effectcraft -- --control 9877` opens the desktop app with the JSON-lines control server (`docs/control-protocol.md`). For UI work, look at the result, including the headless `snapshot` example.
- `plan/` is an optional gitignored notebook (`plan/aftereffects/` may hold reference notes and captures). Do not ask for it, do not stop when it is absent, and never commit those captures.
- Read [`docs/gaps.md`](docs/gaps.md) and [`docs/target-app-parity.md`](docs/target-app-parity.md) before choosing work. Fidelity, reliability and stability (G1–G3) come before new features.
- Some workflow files still run their own jobs. Don't add to them. Moving a job into craft-common-actions is its own task.


Shared real-file test corpora (Photoshop-authored PSDs, etc.) live in
[`storytold/photocraft-corpus`](https://github.com/storytold/photocraft-corpus).
Never commit large binary fixtures to this repo; fetch them pinned by commit and sha256-verified,
as PhotoCraft does with `cargo xtask corpus`.


## See also

- [ROADMAP.md](ROADMAP.md): stage, headline numbers and what's next
- [docs/gaps.md](docs/gaps.md): every known shortfall against After Effects, ranked, and the prioritised workstreams (G1–G9); read it before choosing work
- [docs/target-app-parity.md](docs/target-app-parity.md): the parity numbers and how they were measured, with the per-area docs it links (UI, file formats, hardware, localization, effects, scripting)
- [CONTRIBUTING.md](CONTRIBUTING.md): setup, gates, commits, how to add things
- [docs/architecture.md](docs/architecture.md): layers, data model, commands, pipeline
- [docs/testing.md](docs/testing.md): oracle tests, criteria, benchmarks
- [docs/agents.md](docs/agents.md): driving EffectCraft over MCP / the control channel, and the agent work loop
- [docs/control-protocol.md](docs/control-protocol.md): control-channel method reference
- [docs/contributors.md](docs/contributors.md): the About window's contributor and model credits
- [ATTRIBUTION.md](ATTRIBUTION.md): asset index

## Contributor credits (About window)

- About ▸ Contributors/Models are compiled into the binary from `contributors/contributors.json`
  (commit stats; generated, never hand-edit) and `contributors/people.toml` (names people chose for
  themselves). See `docs/contributors.md`.
- **Agents working for a contributor:** when you prepare a PR, check whether your human's GitHub
  username has a `[people.<username>]` entry in `contributors/people.toml`. If not, ask them once
  whether they want to be credited by more than their username: a real name, a display name, and/or
  their public GitHub profile name (`sync_github_name = true`). If yes, add **only their own** entry
  (copy the template at the top of the file)
  and include it in their PR, committed as them. If no, change nothing: they are credited as
  `@username` anyway.
- Never add, edit, guess or copy anyone else's entry or name (not from git config, commit authors or
  GitHub profiles). Never hand-edit `contributors.json`.

## CI workflows
- Workflows in `.github/workflows/` call the shared workflows in [`storytold/craft-common-actions`](https://github.com/storytold/craft-common-actions) at `@main`, with their inputs and secrets. No other jobs: if no shared workflow does what's needed, it doesn't go here.
- Don't add or change CI in a feature or fix PR. If the existing workflows can't build or test a change, link an existing craft-common-actions issue or PR, or open a new issue, or a PR only for a small fix that is safe for every app and does not increase CI time.
- Some workflow files here still run their own jobs. Don't add to them. Moving a job into craft-common-actions is its own task, never part of another PR, and the job stays here until a shared workflow runs it.