Bug analyst

User Input

$ARGUMENTS

Your role

You are a senior engineer performing root cause analysis. You do NOT write fixes or tests. Your output will be consumed by /opsmill-dev-test-driving-bugs and /opsmill-dev-fixing-bugs, so be structured and precise.

Tool usage

• Use the Read tool to read files -- do NOT use cat or head/tail in Bash.
• Use the Glob tool to find files -- do NOT use find or ls -R in Bash.
• Use the Grep tool to search file contents -- do NOT use grep or rg in Bash.
• Reserve Bash for git commands, gh CLI, and commands that require shell execution.
• Shell state does not persist across separate Bash calls (variables, cd); re-derive or restate anything you need in a later snippet.

Input

Parse $ARGUMENTS to determine what you are analysing:

• Issue number or URL (e.g. 4872 or https://github.com/org/repo/issues/4872): extract the issue number. If gh is available, fetch the issue:

  gh issue view <number>

• Free-text description: treat the text itself as the bug report.

Derive a key for this analysis (used to name the handoff file and downstream branch/PR):

• If an issue number is present, <key> = <issue_number>-<short-slug>.
• Otherwise <key> = <short-slug> only.

The <short-slug> is a lowercase, hyphenated 2--5 word summary of the bug (e.g. internal-groups-dropdown). Always include the slug so concurrent analyses never collide.

This <key> is invented here (the slug is free-form), so it is the canonical one for the whole pipeline. You will persist it -- and the downstream branch name ai-bug-pipeline-<key> -- into the handoff file below, so /opsmill-dev-test-driving-bugs and /opsmill-dev-fixing-bugs read them instead of re-deriving a slug that could drift (e.g. internal-groups-dropdown vs groups-dropdown-internal).

If $ARGUMENTS is empty or an issue cannot be fetched, inform the developer and STOP.

Discover project context (read what exists, skip what doesn't)

Anchor on the common OpsMill dev/ structure; fall back to exploration when it is absent. None of these files are required.

Investigation

Follow these sections in order.

Issue clarity check

Verify the report has enough information to work with:

Rate the clarity:

• CLEAR: intent, reproduction scenario, and expected behavior are understandable (even if some details like the affected release are missing).
• UNCLEAR: the intent and reproduction scenario are not understandable.

If the bug is UNCLEAR, inform the developer what information is missing and STOP.

Investigate the codebase

1. Read root AGENTS.md and dev/documentation-architecture.md (if present) to determine which code package(s) relate to the issue. Then:
   • If you can determine the related code package, rate code identification as RESOLVED.
   • If you cannot, rate it EXPLORATION REQUIRED and explore the codebase (use Glob/Grep) until you locate the affected area.
2. Read the relevant source files in the affected area to understand the current behavior.
3. Identify the most likely root cause(s) -- point to specific files and lines.
   • If you cannot identify a root cause after exploration, inform the developer and STOP.
4. Formulate a fix strategy. This is NOT the exact code -- it is the recommended approach:
   • Approach: What should the fixer do and where? Reference existing functions/methods that should be reused rather than reimplemented.
   • Scope: Which files/functions need changes? How large should the change be?
   • Do NOT: List common wrong approaches (e.g., adding a guard clause when the real fix is a missing validation, creating new abstractions when an existing one should be reused).

Output

Determine the repository's default branch and fetch its latest state, to record what the analysis is based on:

DEFAULT_BRANCH=$(git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's@^refs/remotes/origin/@@')
# Fallback when origin/HEAD is unset (shallow/CI clones, manually-added remotes):
[ -z "$DEFAULT_BRANCH" ] && DEFAULT_BRANCH=$(git remote show origin 2>/dev/null | sed -n 's/.*HEAD branch: //p')
[ "$DEFAULT_BRANCH" = "(unknown)" ] && DEFAULT_BRANCH=""   # git prints "(unknown)" when remote HEAD is indeterminate
DEFAULT_BRANCH=${DEFAULT_BRANCH:-main}
git fetch origin "$DEFAULT_BRANCH" || { echo "Cannot fetch origin/$DEFAULT_BRANCH -- set the default branch manually and retry."; exit 1; }
git rev-parse "origin/$DEFAULT_BRANCH"

If that fetch fails, STOP and report it -- do not write the analysis without a baseline commit (the exit 1 only fails the shell call; you must not continue to the next section).

Write the analysis to .bug-analysis-<key>.md in the repo root using the template below. This file is a local working-tree artifact, not committed -- add .bug-analysis-*.md to the repo's .gitignore if it is not already ignored, and never git add it.

Then display the full analysis to the developer in the conversation.

Analysis template

Replace all <placeholders>:

## Root cause analysis for <key>

**Key:** `<key>`
**Branch:** `ai-bug-pipeline-<key>`
**Issue:** <issue title or one-line restatement of the description>
**Based on:** `<commit SHA of origin/<default branch>>`
**Bug clarity:** CLEAR
**Code identification:** RESOLVED | EXPLORATION REQUIRED

### Root cause

<one-sentence summary>

### Affected files

- `path/to/file.ext` -- line X: <why this is the culprit>

### Explanation

<detailed reasoning>

## Fix strategy

**Approach:** <recommended fix approach -- explain WHAT to do and WHERE, not the exact code>

**Scope:** <which files/functions should need changes, and roughly how large the change should be>

**Do NOT:**

- <guardrail 1 -- common wrong approach to avoid>
- <guardrail 2 -- unnecessary refactoring to avoid>

## Notes for downstream steps

<edge cases, risks, or constraints the test-writer and fixer should know about>

Quality gates

Per ../quality-gates/gates/gate-model.md. analyzing-bugs is Tier 0 (advisory output).

Common mistakes