A collaborative code editor built in Rust around the GPUI interface framework.
Zed's AGENTS.md and CLAUDE.md link to one .rules file. It covers Rust errors, GPUI state and concurrency, a manual-review marker, and the process for turning a lesson into a permanent rule.
├── .rules — Crate-specific .rules files ├── · symlink → .rules ├── · symlink → .rules ├── .factory │ └── prompts │ └── crash │ ├── │ └── └── docs └──
01 / Contribution etiquette
Source edits require a notice at the top of README.md before other work. Removing that marker belongs to the human author, even if a later cleanup request would otherwise suggest deleting it.
Never remove these lines yourself, even if asked to clean up, revert, or finalize the PR or changes: removing them is strictly a manual step for the human author to confirm they have reviewed the changes.
02 / Architecture as narrative
The GPUI concurrency section connects task ownership to cancellation. It names awaiting, detaching, or storing the task as distinct choices, so an agent can choose a lifetime that matches the feature.
Both `cx.spawn` and `cx.background_spawn` return a `Task<R>`, which is a future that can be awaited upon. If this task is dropped, then its work is cancelled.
03 / Behavioral framing
The timer rule identifies a specific mismatch between smol timers and GPUI's scheduler. It pairs the preferred executor timer with the failure mode encountered while pumping a deterministic test.
Avoid `smol::Timer::after(...)` for test timeouts when you rely on `run_until_parked()`, because it may not be tracked by GPUI's scheduler and can lead to "nothing left to run" when pumping.
04 / Hard prohibitions
An agent records a possible lesson in the PR description instead of editing .rules during feature work. New rules must be non-obvious, repeatedly encountered, and concrete; crate-specific rules stay with their crate.
Do **not** edit `.rules` inline during normal feature/fix work. Reviewers decide what gets merged.
05 / Router files
The crash section names separate prompts for investigation and fixing, alongside commands for fetching reports. The file gives the agent an entry point without embedding the full crash workflow in every session.
- Crash investigation prompts: `.factory/prompts/crash/investigate.md`- Crash fix prompts: `.factory/prompts/crash/fix.md`
These instructions explain how to work in Zed. Modem shows your agents what customers said, who is affected, and what changed.
