git:20260721.df395b3 to git:20260818.874d2e4

- description: Watch an Elixir/Phoenix PR for new review comments (bot + human) and

- CI results via a background watcher that wakes Claude only on real events. Use after

- opening a PR or pushing, while waiting on CI or reviewers.

- # Watch PR (Token-Conscious)

-

- Watch a PR's reviews, comments, and CI with a background watcher that

- wakes Claude ONLY on real events — no foreground sleep loops, no context

- bloat. The watcher polls quietly in its own process; nothing enters

- context until something genuinely changed.

-

- ## Usage

- ```

- phx-watch-pr 42 # watch reviews + comments + checks

- phx-watch-pr 42 --checks-only # CI only (delegates to gh pr checks --watch)

- phx-watch-pr 42 --fix # on actionable review, draft fixes too

- phx-watch-pr 42 --codex # + request Codex cloud review, loop until clean

- phx-watch-pr 42 --codex --codex-rounds 2 # cap re-review rounds (default 3)

- ```

- 1. **NEVER foreground-poll with `sleep` in the session** — use the

- background watcher (Monitor / run_in_background). Foreground polling

- bloats context and straddles the 5-min cache TTL

- 2. **Deltas ONLY enter context** — never dump full `gh` JSON. The watcher

- emits one-line events; read `.claude/watch/pr-{n}.jsonl` on demand

- 3. **Silence is not success** — the watcher MUST emit on PR closed/merged,

- CI failure, repeated gh errors, and watchdog timeout — not just "new

- comment". A silent watcher looks identical to a hung one

- 4. **NEVER auto-post replies or auto-push** — hand off to `phx-pr-review`

- for responses; show drafts and get approval. ONE exception: passing

- `--codex` IS the consent to post the `@codex review` trigger comment

- (and its per-round re-requests) — nothing else is ever auto-posted

- 5. **Bound every watch** — default MAX_DURATION 3600s (7200s with

- `--codex`); always stop on terminal state. Codex rounds are bounded by

- `--codex-rounds` (default 3) — each round costs cloud quota

-

- ## Workflow

-

- ### Step 1: Parse Arguments

-

- Extract PR number (from number or URL — URL also yields the repo). Detect

- `--checks-only` / `--fix` / `--codex` / `--codex-rounds N`. Baseline

- timestamp = now; events are "new since baseline", so old reviews don't

- re-fire.

-

- With `--codex`, the **default is to POST `@codex review`** — the flag IS

- that consent (Iron Law 4). Skip the trigger ONLY when the connector bot

- (`chatgpt-codex-connector[bot]`) has itself reacted to / reviewed the

- current head SHA. The repo's CI "Codex" check and any local `codex exec` /

- `phx-review --codex` / `phx-codex-loop` run are DIFFERENT mechanisms from

- the GitHub connector — they NEVER satisfy the skip. When unsure, post. The

- connector auto-registers PRs on ready (its absence surfaces later as

- `codex_timeout`), so check ITS reactions before posting a redundant trigger:

-

- ```bash

- HEAD_AT=$(gh api "repos/{owner}/{repo}/commits/$(gh pr view {n} --json headRefOid -q .headRefOid)" --jq .commit.committer.date)

- BOT=$(gh api "repos/{owner}/{repo}/issues/{n}/reactions" | jq -r --arg t "$HEAD_AT" \

- '[.[] | select(.user.login == "chatgpt-codex-connector[bot]" and .created_at >= $t) | .content] | unique | join(",")')

- ```

-

- (`gh api --jq` accepts no `--arg` — pipe through standalone `jq`.)

-

- **Definitive check first**: a **connector-bot** comment or review containing

- `Reviewed commit: {sha}` that matches the current head sha means that

- state IS reviewed (clean if it says "Didn't find any major issues") —

- trust it over timestamps, which are client-set and can skew. Then:

-

- | Connector-bot signal on current head | Action |

- |-------------------------------|--------|

- | `+1` reaction | Connector already reviewed this head clean — no trigger, no codex round; watch CI/humans only |

- | `eyes` + a codex review already submitted since `$HEAD_AT` | Findings already posted — skip the watch; run the `codex_review` action (Step 3) now |

- | `eyes` only | Review in flight — do NOT post; export `WATCH_CODEX=1 WATCH_CODEX_SINCE=$HEAD_AT` (no trigger id) and watch |

- | none (or reactions predate head) | Post the trigger and capture its id: |

-

- ```bash

- TRIGGER_ID=$(gh api --method POST "repos/{owner}/{repo}/issues/${PR}/comments" \

- -f body="@codex review" --jq '.id')

- ```

-

- Export `WATCH_CODEX=1 WATCH_CODEX_TRIGGER_ID=$TRIGGER_ID` to the watcher

- env and set MAX_DURATION 7200. Round counter starts at 1.

-

- ### Step 2a: `--checks-only` Path

-

- No custom poller needed — `gh pr checks --watch` blocks until all checks

- finish, then exits. Run via Bash with `run_in_background: true`:

-

- ```bash

- gh pr checks {n} --watch --fail-fast --interval 10

- ```

-

- Exit code is the signal: `0` = pass, `1` = fail, `8` = pending. On exit,

- report the conclusion; on failure, offer `phx-investigate` with the

- failing job log (`gh run view {run-id} --log-failed`).

- ### Step 2b: Full Watch Path

- Start the **Monitor tool** (preferred — streams each event line back) on:

- ```

- scripts/watch-pr.sh {n} reviews,comments,checks

- Monitor is a deferred tool — load its schema FIRST via ToolSearch

- (`select:Monitor`); calling it blind fails with InputValidationError

- (params are `command`, `description`, `timeout_ms`, `persistent` — do

- not invent others). Set `timeout_ms` = MAX_DURATION × 1000.

- Where Monitor is unavailable

- (Bedrock/Vertex/Foundry), run the same script via Bash

- `run_in_background: true` — it exits on the first terminal event instead.

- Stay idle or keep working until an event lands.

- ### Step 3: React Per Event

- | Event | Action |

- |-------|--------|

- | `review` / `comment` (actionable) | Summarize the delta; with `--fix` draft fixes + `mix compile && mix test`; route reply drafting to `phx-pr-review {n}` |

- | `check` conclusion `failure` | Offer `phx-investigate` on the failing job |

- | `codex_ack` | Note "codex is reviewing (~15–20 min on large PRs)"; keep waiting |

- | `codex_review` | Stop the watcher. Run `phx-pr-review {n} --bots-only` (fix → reply → resolve; user approves and pushes). If rounds < `--codex-rounds`: post `@codex review` again, restart watcher with the new trigger id, round+1. Else: report remaining findings, stop |

- | `codex_clean` | Codex is clean (👍 reaction OR a "Didn't find any major issues" bot comment). If checks also green → terminal success "codex + CI clean"; else keep watching CI |

- | `codex_timeout` | Inform: repo likely lacks the Codex connector; continue as a plain watch |

- | `merged` / `pr_closed` / `watchdog` / `watch_error` | Stop, report final state |

- A `codex_review` whose `phx-pr-review --bots-only` fetch finds zero

- unresolved codex threads also counts as clean (summary-only review).

- ### Step 4: Stop

- The watcher self-terminates on terminal states. To stop early: `TaskStop`

- the background task or cancel the monitor.

- ## Integration

- ```text

- push / open PR → phx-watch-pr {n} ──(new review)──► phx-pr-review {n}

- ├──────(CI fail)─────► phx-investigate

- ├──(--codex: codex_review)─► phx-pr-review --bots-only → push → re-request → watch (≤3 rounds)

- ├──(--codex: codex_clean + CI green)─► done: codex + CI clean

- └──────(merged)──────► done

- ```

- ## References

- - `references/watcher-mechanics.md` — cache TTL math, Monitor vs run_in_background vs ScheduleWakeup, rate-limit notes