fix-issue

name	fix-issue
description	End-to-end workflow to fix a GitHub issue in marin-community/marin.

Skill: Fix GitHub Issue

Fix the Github issue indicated by the user.

Background

Read first:

@AGENTS.md

Complete tasks in order; the task list is at the end of this document. If you cannot complete a task, write a Github comment with your last status and why.

Writing Style for All GitHub Comments

Be terse. Every sentence must convey new information:

• No preamble, filler, or editorializing ("I've thoroughly investigated...").
• No repeating the issue body.
• No restating what code does when a link suffices.
• Max 3-4 sentences of prose per comment section. Use links and code, not words.
• Annotate code links, don't narrate them. Bad: "The transfer happens in arrow_flight.py where the implementation copies data from TPU to CPU". Good: arrow_flight.py#L384 - TPU→CPU copy.

Research

Use gh to fetch the issue. Read the codebase for all relevant source files. Post a single comment with two sections: Research and Proposed Fix.

Before writing code, run a duplicate-work preflight:

• Check open PRs for the same issue or subsystem (gh pr list --state open --search "<issue-id or keyword>").
• Check open issues for the same root cause (gh issue list --state open --search "<keyword>").
• If overlapping work exists, do not open a parallel implementation PR. Add a short issue comment summarizing what you found, and either hand off to the existing PR or scope your change to non-overlapping follow-up work.

Research section

Title: # Research

• 2-3 sentences: what's broken/missing and why (root cause, not symptoms).
• A **Relevant code** list: max 5 links, each with a short (<10 word) annotation.

Example:

jax.device_get() produces non-contiguous memory layout, limiting TPU→CPU transfer to ~1GB/s (expect 4-7GB/s). No parallelization across shards.

Relevant code

• arrow_flight.py#L384 - TPU→CPU copy
• jax.py#L394-L402 - transfer impl
• base.py#L32-L35 - transfer mode defs

Proposed Fix section

Title: # Proposed Fix

There are 2 cases:

• Bug fix: Show the call chain that triggers the error, then state the fix in one sentence. Include a code snippet only if the fix is non-obvious.

  env.run() returns a tuple; foo() assumes an object and calls .abc(). Fix: unwrap the tuple in RolloutWorker._step() before passing to foo().

• Design change: The design doc replaces the # Proposed Fix section. Write it per .agents/skills/write-design-doc/ directly in the issue comment (agents cannot commit files before the PR). The 3-4 sentence prose cap applies to # Research; the design doc follows its own length guidelines. Keep everything in one comment.

In both cases: find the minimally disruptive fix. Do not over-engineer.

Implementation

Implement changes in a branch named agent/{YYYYMMDD}-fix-{issue-id}. You may create branches on github and submit PRs from them.

Testing

• Write the test before the fix, then validate the fix works.
• Use an existing test file in tests/ if appropriate.
• Never use mocks.
• Keep tests simple and minimal. Do not test obvious behavior like "object has an attr".
• Run ./infra/pre-commit.py --all-files --fix and resolve all reported issues.
• Run uv run pytest -m 'not slow' and ensure all tests pass before uploading.

Uploading

When all tests pass, upload your branch and open a PR following .agents/skills/commit/SKILL.md exactly — use the plain-text format it specifies (no markdown headers, bullet lists, or ## Summary sections; violations are rejected). Attach a comment to the Github issue summarizing the fix.

Verify CI Status

After opening the PR, verify CI checks pass:

• Monitor with gh pr view <number> --json statusCheckRollup.
• Wait for unit tests; if they fail, investigate and push fixes.
• Do not consider the PR complete until all relevant checks pass.

Key checks: unit tests (must pass), lint-and-format (must pass), build-docs (should pass if you modified documentation).

Tasks

The tasks for this skill:

• Fetch issue information
• Research codebase for all relevant source files
• Run duplicate-work preflight against open PRs/issues
• Formulate fix and post Research + Proposed Fix comment
• Create branch for the changes
• Write a test case as needed for changes
• Implement changes until all tests pass
• Run ./infra/pre-commit.py --all-files --fix and resolve all issues
• Upload branch to github
• Open pull request
• Verify CI checks pass and address any failures (by polling gh pr view)
• Update comment with final status

If at any point you are unable to proceed, you must add a comment to the Github issue with your last status.

RULES

0. Never credit yourself in commits or comments.