# T1.2.1 — Add rustdoc on `MediaType` variants and methods

**Status:** Approved
**Agent:** Kimi Code CLI
**Started:** 2026-05-11T07:23Z
**Completed:** 2026-05-11T07:24Z
**Commit:** see git log
**PRD:** ../PRD-wire-format-v2.md

## What I changed

- `crates/wzp-proto/src/media_type.rs:7-10` — added `///` doc comments to all 4 variants (`Audio`, `Video`, `Data`, `Control`)
- `crates/wzp-proto/src/media_type.rs:14` — added `///` doc on `to_wire`
- `crates/wzp-proto/src/media_type.rs:18` — added `///` doc on `from_wire`

## Why these choices

Follow-up from T1.2 review: coding standard #9 requires `///` on all public items. Added concise one-line docs matching the examples from the task spec.

## Deviations from the task spec

None.

## Verification output

```bash
$ cargo doc -p wzp-proto --no-deps 2>&1 | grep -i "missing" || echo "no missing-doc warnings"
no missing-doc warnings
```

```bash
$ cargo clippy -p wzp-proto --all-targets -- -D warnings -W missing_docs 2>&1 | grep "media_type.rs:" | head -10
# (no output — no missing-docs in media_type.rs)
```

```bash
$ cargo build -p wzp-proto
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.49s
```

```bash
$ cargo test -p wzp-proto --no-fail-fast
running 112 tests
test result: ok. 112 passed; 0 failed; ...
```

```bash
$ cargo fmt --all -- --check
# (clean)
```

## Test summary

- Tests added: 0
- Tests modified: 0
- `cargo clippy -p wzp-proto --all-targets -- -D warnings`: pass
- `cargo fmt --all -- --check`: pass

## Risks / follow-ups

None.

## Reviewer checklist (filled in by reviewer)

- [x] Code matches PRD intent
- [x] Verification output is real (re-run if suspicious) — re-ran `clippy -W missing_docs | grep media_type.rs:` → zero hits.
- [x] No backward-incompat surprises
- [x] Tests cover the new behavior
- [x] Approved

### Reviewer notes (2026-05-11)

Approved. All 4 variants and both methods carry concise, accurate `///` docs. Both Verify commands run this time. Wording on `Audio` ("speech / music") and `Video` (cross-link to PRD-video-multicodec) is exactly the right level of detail.
