---
name: review-issue
description: Review an incoming external issue (and any gated-closed PR behind it) and decide whether to assign the contributor or decline. Use when the maintainer says "look at this issue", "review issue #N", "should we take this", or asks whether to assign someone. Assigning the author auto-reopens their PR for normal review. This is the entry point for incoming-issue triage — distinct from review-pr, which responds to bot reviews on your own open PR.
---

# Triaging contributions under the issue-link gate

FastMCP auto-closes external PRs unless the author is **assigned to a referenced issue**
(see [require-issue-link.yml](../../../.github/workflows/require-issue-link.yml)). The practical
effect: contributors open an issue, open a PR, get auto-closed, and ask to be assigned. The
maintainer almost never sees the PR directly — **the issue is the decision point**, and
**assigning the author is the single action that reopens their PR** and sends it into review.

This skill turns "look at this issue" into one of two outcomes:
- **Assign** — the issue is valid, we want it fixed, an external PR is appropriate, and a sound
  PR already exists → assign the author (auto-reopens the PR) and queue it for code review.
- **Decline** — leave the issue/PR closed and explain why on the issue.

Be opinionated about declining. The gate moved spam from junk PRs to junk issues; this skill is
worthless if it just rubber-stamps assignment. Assignment is a commitment to review and likely
merge, not a courtesy.

## How the gate works (the part that matters here)

- External PR is closed unless its body has `Fixes/Closes/Resolves #N` **and** the author is
  assigned to issue `#N`.
- **Assigning the author to the issue auto-reopens their closed PR** and re-runs the check —
  this is the lever you pull. `gh issue edit N --add-assignee <login>`. The assignment fires a
  `require-issue-link` run; expect it to pass. If it fails, the gate itself misbehaved (not the
  PR) — investigate the run, don't re-assign.
- Maintainer-authored PRs are exempt. A `trusted-contributor` label exempts a contributor up
  front. Reopening the PR or removing the `missing-issue-link` label applies a sticky
  `bypass-issue-check`.
- Sibling bots have usually already run on the issue: `marvin-triage-issue` (investigates +
  recommends), `marvin-dedupe-issues` / `auto-close-duplicates` (dupes), `auto-close-needs-mre`
  (missing MRE). Read their comments before re-deriving anything.

## Step 1 — Orient

Read the issue, its bot triage, and any PR behind it. Run these together:

```bash
gh issue view N --repo PrefectHQ/fastmcp \
  --json number,title,state,author,body,labels,assignees,comments
# Find PRs the author opened that reference this issue (they're likely CLOSED):
gh pr list --repo PrefectHQ/fastmcp --state all --search "author:<login> #N in:body" \
  --json number,title,state,url,labels
```

If a PR exists, pull its metadata and any review-bot comments (CodeRabbit, Codex). Treat the bot
comments as leads, not conclusions — they often don't run on closed PRs at all, and even when
they do you still owe the PR your own read:

```bash
gh pr view <pr> --repo PrefectHQ/fastmcp --json number,title,body,labels,files,additions,deletions
gh pr view <pr> --repo PrefectHQ/fastmcp --comments
```

## Step 2 — Classify the issue (is it valid AND a real bug?)

- Is there a real, reproducible problem? For bugs, demand an MRE that shows FastMCP misbehaving
  — not user config error, not a question, not an upstream-SDK issue.
- Is it a duplicate or already fixed on `main`? Check the dedupe bot's comment and recent commits.
- If the issue itself is weak, **stop here and decline** — don't evaluate the PR. A good PR
  attached to a bad issue is still declined.

**A reproducible MRE is not the same as a bug.** This is the trap that produces wrong verdicts:
an MRE can demonstrate real, observable behavior that is nonetheless *not a bug*, because it
violates no contract the framework intends to hold. The decisive question is not "does this
reproduce?" but "does the demonstrated behavior violate the intended contract for this API?" A
shared-mutable-state MRE only matters if callers are *supposed* to mutate that state; an
ordering/timing MRE only matters if the framework promises an order; a "wrong" value only matters
relative to what the API guarantees. An MRE that has to reach past the supported surface to
trigger the behavior (mutating a field meant to be set only at construction, depending on an
internal that isn't part of the public contract) is showing you a property, not a defect.

You usually cannot read the intended contract off the code — the code shows what it *does*, not
what it *promises*. **The maintainer is often the only authoritative source for the contract, so
stopping to ask is legitimate and expected here.** Ask "is X a supported pattern / does this API
promise Y?" before sinking time into investigating a fix. If the behavior is in-contract correct,
decline — no matter how cleanly the PR fixes it, and no matter how real the MRE looks.

## Step 3 — Investigate the PR (mandatory; do NOT skip if a PR exists)

The most common failure of this skill is judging a PR from the diff hunk and the PR description
alone. That is a cursory review and it produces wrong verdicts — a redundant-looking conditional
can be a real bug fix; a tidy-looking diff can patch the wrong layer. **You cannot assess a PR
without reading the code it changes in context.** Reading `gh pr diff` is necessary but never
sufficient.

Do all of this before forming any opinion on quality:

1. **Read the diff in full**, then **open every file it touches in the repo** (`Read`, not just
   the patch). The hunk shows *what changed*; the file shows *what it changed into*.
2. **Trace the functions and values the change depends on.** Grep for the called functions,
   the fields being set, and the defaults. If the PR overrides or replaces a value, find what
   produced the original value and what consumes it downstream.
3. **Establish the actual root cause from the issue's MRE**, then check whether the change fixes
   *that* — at the layer where the bug originates, not a compensating patch elsewhere.
4. **Check consistency with adjacent code.** Does the new value/behavior match how nearby code
   already handles the same case? An inconsistency is a real finding; a match is evidence the fix
   is correct.
5. **Run or read the tests** the PR adds/changes — do they actually exercise the bug, and would
   they fail without the fix?

Write down, for yourself, a one-line answer to: *what was broken, where, and does this change fix
it there?* If you can't answer from evidence you've actually read, you haven't investigated yet.

Then separate findings by severity: a **cosmetic** nit (style, a redundant-but-harmless line) is a
review comment, not a blocker. A **substantive** defect (wrong layer, breaks an adjacent path,
doesn't actually fix the MRE) changes the verdict. Don't let a cosmetic nit read as a reason to
decline, and don't let a clean style read as evidence of correctness.

## Step 4 — Decide if an external PR is appropriate (CONTRIBUTING.md)

This is the gate CONTRIBUTING.md actually enforces. Map the change to a category:

- **Simple, well-scoped bug fix** → external PR welcome. Assignable.
- **Docs / typo / example fix** → welcome. Assignable.
- **Auth provider** → assignable (auth is the one integration exception).
- **Enhancement / feature** → needs a maintainer-approved design proposal *in the issue first*.
  Do **not** assign just because code exists. If the proposal is sound, the path is "approve the
  approach in the issue, then assign" — not "assign because they were fast."
- **Third-party integration** (middleware, provider adapters, non-auth) → decline; belongs in a
  separate package.
- **Sweeping / multi-subsystem change with no prior discussion** → decline.

Combine the category with the Step 3 investigation: does it fix the cause or paper over a symptom?
Does it read like unedited LLM output (verbose body, speculative/shotgun changes)? CONTRIBUTING.md
says we close those — a closed PR that reads that way is staying closed.

## Step 5 — Recommend, then act

Present a short verdict to the maintainer before mutating anything: **assign** or **decline**,
one or two sentences of reasoning, and the exact command you'll run. Wait for confirmation on
borderline calls; for clear-cut ones you may proceed and report.

**Assign** (valid issue + appropriate external contribution + sound PR exists):

```bash
gh issue edit N --repo PrefectHQ/fastmcp --add-assignee <login>
```

That reopens the PR automatically. Then hand off to code review — invoke the `code-review` /
`review-pr` skills on the reopened PR. Assignment is not approval; the code still gets the normal
pass.

If a PR's head branch was deleted, assignment can't reopen it — the workflow comments asking the
author to open a fresh PR. Don't try to force it.

**Decline** (invalid issue, wrong contribution type, or low-quality PR): leave it closed and
comment on the **issue** explaining the decision, pointing to the relevant CONTRIBUTING.md
section. Per repo rules, use `--body-file`, never inline `--body`, for any comment that could
contain `$`, backticks, or code:

```bash
gh issue comment N --repo PrefectHQ/fastmcp --body-file /tmp/triage-reply.md
```

Keep the reply short and point to the relevant CONTRIBUTING.md section. (If a `github-reply`
skill is available for maintainer voice/tone, use it — but it isn't required.)

## What this skill does NOT do

- It doesn't bypass the gate via `trusted-contributor` / `bypass-issue-check` — that's a
  deliberate maintainer escalation, not a triage outcome.
- It doesn't merge. Assignment → reopen → review → (maybe) merge are distinct steps.
- It doesn't re-run the first-pass triage the bots already did; read their output instead.