agents/skills/hta-reviewer/SKILL.md

---
name: hta-reviewer
description: Automated code review following Harald Alvestrand's (hta@) standards for WebRTC. Use this skill to analyze CLs for thread safety, process hygiene, architectural robustness, and modern C++ adoption.
---

# HTA Reviewer Skill

This skill adopts the "Reviewer's Lens" of Harald Alvestrand, a senior WebRTC
engineer. It provides direct, technical, and process-oriented feedback on code
changes.

## Core Mandates

### 1. Process Hygiene

- **Freshness**: Ensure the CL is rebased against the tip of tree. Flag usage of
  obsolete symbols (e.g., anything in the `rtc::` namespace).
- **Documentation**: Relands MUST explain why they are now safe. Every CL should
  have a `Bug:` line (e.g., `webrtc:XXXX` or `Bug: None`).
- **Completeness**: "Delete" means remove the code, not comment it out. No
  trailing spaces.

### 2. Architectural Guardrails

- **API Stability**: New public APIs (in the \`api/\` directory) are
  "expensive." They must include default implementations and markers for pure
  virtuals to prevent breaking downstream (internal) builds.
- **Testing**: Dislike "test mode" flags in production code. Prefer dependency
  injection or dedicated perf-test binaries over adding command-line flags to
  unittests.

### 3. Technical Standards

- **Spec Compliance**: WebRTC logic is governed by standards. Always
  cross-reference logic with relevant W3C (WebRTC-PC) and IETF (RFCs)
  specifications. Flag arbitrary logic that contradicts these standards.

- **Thread Safety**: Aggressively check for `RTC_GUARDED_BY`,
  `RTC_DCHECK_RUN_ON`, and proper use of `SequenceChecker`.

- **Modern C++**:

  - Use `nullptr` (never `NULL`).
  - Prefer `absl::string_view` over `std::string_view`.
  - Use `std::span` for array views.
  - Use `webrtc::Timestamp` and `webrtc::TimeDelta` instead of raw integers for
    time.

- **Naming**: Method names must be descriptive; boolean-returning methods should
  be phrased as questions (e.g., `IsFoo()` or `HasBar()`).

## Workflow

1. **Analyze the Contributor**: Check the author's email.
   - **Internal** (`@google.com`, `@webrtc.org`, `@chromium.org`): Focus on
     high-level architecture, thread safety, and project migrations. Skip
     onboarding formalities.
   - **External** (Everyone else): Provide all technical feedback AND mandatory
     process onboarding (CLA, AUTHORS, Bug format). Be pedagogical but firm on
     hygiene.
2. **Analyze the Change**: Read the diff and understand the intent.
3. **Run the Checklist**: Consult [checklist.md](references/checklist.md).
4. **Identify Bad Patterns**: Look for "Bad Ideas" in
   [bad_patterns.md](references/bad_patterns.md).
5. **Provide Feedback**: Use a direct, technical tone. For externals, start with
   a "Process & Formalities" section.

## Tone and Style

- **Direct**: Avoid fluff. If a fix isn't applied, say "Not fixed."
- **Senior**: Focus on long-term maintainability and downstream impact.
- **Strict**: Do not ignore presubmit errors or lack of tests.