# Agent Instructions — jmap-chat-client
## 🧬 Sibling of the canonical jmap-mail-client — mirror its shape
This crate is a **sibling under the canonical `jmap-mail-client`
extension-client template**. Module layout, `Jmap*Ext` extension-trait
shape, `SessionClient` shape, `with_*_session` accessor, `/get` and
`/set` builder patterns, Id-validation helpers, doc-comment style,
and test layout must mirror `jmap-mail-client`. Differences are
*only* the spec content (the JMAP Chat draft here; RFC 8621 in
mail-client).
**The propagation rule** (workspace AGENTS.md "Canonical Templates"):
- If you reshape this crate in a way that diverges from
`jmap-mail-client`, **change `jmap-mail-client` first, then
propagate** to every other extension-client sibling in the same
pass.
- If `jmap-mail-client` changes, propagate the change here in the
same pass (or file a follow-up sweep bead before merging).
- A divergent sibling without a matching change on the canonical
is a regression of the cookie-cutter intent — review will catch
it.
## What This Is
JMAP Chat extension client methods (draft-atwood-jmap-chat-00) on
top of `jmap-base-client`. Implements `Chat/*`, `Message/*`, `Space/*`,
`ChatContact/*`, `ReadPosition/*`, push subscriptions, and the JMAP
Chat WebSocket transport.
## Crate Family Context
```
jmap-types
└── jmap-base-client
├── jmap-mail-client (canonical extension-client)
└── jmap-chat-client ← this crate (sibling)
↑ also depends on jmap-chat-types for wire types
```
## Build & Test
```bash
cargo fmt --all
cargo clippy -p jmap-chat-client --tests -- -D warnings
cargo test -p jmap-chat-client
RUSTDOCFLAGS="-D warnings" cargo doc -p jmap-chat-client --no-deps --all-features
```
Run all four before considering any work done.
## Source Material
- `~/PROJECT/jmap-chat-spec/draft-atwood-jmap-chat-00.md` — normative
for all method signatures, arguments, and response fields
- `~/PROJECT/jmap-chat-spec/references/rfc8620.txt` — base
get/set/changes/query request and response shapes (normative for
structural fields)
## Restrictions
- Push freely — `git push`, no `pull --rebase` ritual (workspace
AGENTS.md "Git Commit and Push Policy")
- Do not use TodoWrite or markdown task lists — use `bd create`
- Do not add features not in PLAN.md or not explicitly directed
- Any change to this crate that diverges from the canonical
`jmap-mail-client` shape requires landing the canonical change
first and propagating to the six sibling extension-client crates
(see workspace AGENTS.md "Canonical Templates" + the propagation
rule above)