plan-fix

Investigate bugs and create TDD fix plans in PLANS.md. Creates Linear issues in Todo state.

1. Git Pre-flight Check

Before starting any investigation, verify git status:

git branch --show-current
git status --porcelain

• STOP if NOT on main branch. Tell the user: "Not on main branch. Please switch to main before planning: git checkout main"
• STOP if there are uncommitted changes. Tell the user to commit or stash first.
• Check if behind remote: git fetch origin && git status -uno — STOP if behind.

2. PLANS.md Pre-flight

Check if PLANS.md already exists at the project root:

• If it does not exist: OK, you will create it when documenting findings.
• If it exists with Status: COMPLETE: OK, overwrite with new fix plan.
• If it exists with active (non-COMPLETE) content: STOP. Tell the user there is an active plan that must be completed or removed first.
• In all cases, check for an existing section about this bug to avoid duplicates.

3. Verify Linear MCP

Call mcplinearlist_teams. If unavailable, STOP and tell the user: "Linear MCP is not connected. Run /mcp to reconnect, then re-run this skill."

4. Read Project Context

Read CLAUDE.md at the project root (if it exists) to understand:

• Project structure and conventions
• Available MCPs (Linear, Railway, Google Drive, Gemini, etc.)
• Tech stack details
• Testing conventions
• Any project-specific debugging notes

Discover team name: Look for LINEAR INTEGRATION section in CLAUDE.md. If not found, use mcplinearlist_teams to discover the team name dynamically. Store the discovered team name for use throughout the skill.

5. Classify Bug Type

Categorize the reported issue into one of these types:

6. Gather Evidence

6.1 Codebase Investigation

Search the codebase for relevant code using dedicated tools (NOT Bash):

Use Glob and Grep tools to:

• Find the files involved in the bug
• Trace the code path from entry point to the error
• Look for recent changes that might have introduced the bug
• Check test files for related test coverage

6.2 Deployment Logs (if MCP available)

If CLAUDE.md lists deployment MCPs (e.g., Railway MCP) and the bug involves deployment or runtime errors, use the MCP to check logs:

• Check recent deployment status
• Look for error logs around the time of the reported issue
• Check environment variable configuration (without exposing values)
• Review build logs for warnings or errors

6.3 Document/File Issues (if file MCPs available)

• Search for the problematic file using Google Drive MCP
• Read file contents
• Check related data stores (spreadsheets, databases)

6.4 Linear Context

Search Linear for related issues:

• Use mcplinearlist_issues to find existing issues about this bug
• Check if there are related issues that provide context
• Look for previously attempted fixes

6.5 Reproduce the Issue

When possible, try to reproduce:

# Check if tests exist and if they catch the issue
npm test 2>&1 | tail -50

# Check for TypeScript errors
npx tsc --noEmit 2>&1 | tail -50

# Check for lint errors
npm run lint 2>&1 | tail -50

7. Document Findings in PLANS.md

Read references/plans-template.md for the complete template.

Source field: Bug report: [Summary of $ARGUMENTS]

Include: Context Gathered (Codebase Analysis + MCP Context + Investigation), Tasks, Post-Implementation Checklist, Plan Summary. Omit: Triage Results subsection.

The Investigation subsection under Context Gathered must include: bug report, classification (type/severity/affected area), root cause, evidence (file paths with line numbers -- no code blocks), and impact.

8. Create Linear Issue

Create a Linear issue in the discovered team with status "Todo":

1. First, get the team statuses to find the "Todo" state ID:

`` mcplinearlistissuestatuses for team [discovered team name] ``

1. Get available labels:

`` mcplinearlistissuelabels for team [discovered team name] ``

1. Create the issue:

``` mcplinearsave_issue with: - team: [Discovered team name] - title: "[Bug Type] Brief description of the fix needed" - description: | ## Bug Report [Summary of the issue]

## Root Cause [What was found during investigation]

## Fix Plan See PLANS.md for detailed TDD fix plan.

## Files Affected - path/to/file.ts - path/to/another-file.ts

## Acceptance Criteria - [ ] Failing test written and passes after fix - [ ] All existing tests pass - [ ] No TypeScript errors - [ ] Deployed successfully - state: "Todo" - Apply relevant labels (bug, etc.) ```

(Do NOT pass id — omitting it makes save_issue create a new issue.)

1. Update PLANS.md with the created issue key (ADV-xxx).

Prompt/AI Testing Guidelines

When investigating AI/LLM extraction issues:

1. Get the problematic input using file/document MCPs
2. Read current prompt from the project's prompts file (find via codebase exploration)
3. Test variations using AI MCPs if available
4. Document what works - Include the improved prompt in the fix plan
5. Note: Testing MCPs are for debugging, not production use

Example prompt testing workflow:

1. Current prompt extracts field X as null
2. Test prompt variation A: More explicit field description
3. Test prompt variation B: Add context about document layout
4. Variation B correctly extracts the field
5. Add to fix plan: Update prompts file with variation B

Deployment Debugging Guidelines

When investigating deployment issues (if deployment MCPs available):

1. Check status first - Verify MCP/CLI access
2. List recent deployments - Get deployment IDs and statuses
3. Get targeted logs - Search for errors using filters:

- Error-level logs - Specific error types or messages

1. Check environment - Verify configuration variables

9. Error Handling

10. Rules

• NEVER modify application code. This skill only investigates and plans.
• NEVER run destructive commands (no rm, no git reset --hard, no database mutations).
• ALWAYS use TDD approach in fix plans - tests first, then implementation.
• ALWAYS check for existing Linear issues before creating new ones to avoid duplicates.
• ALWAYS include file paths and line numbers in evidence and fix plans.
• ALWAYS propose a branch name following the pattern fix/ADV-xxx-brief-description.
• Discover MCPs from CLAUDE.md - don't hardcode MCP names or paths
• Keep fix plans actionable - another developer (or AI agent) should be able to follow the plan without additional context.
• Severity guidelines:

- Critical: Production down, data loss, security vulnerability - High: Feature broken for all users, significant data issues - Medium: Feature partially broken, workaround exists - Low: Minor UI issue, edge case, cosmetic problem

• DO NOT expose secrets, API keys, or sensitive environment variable values in PLANS.md or Linear issues.
• DO NOT hallucinate code - only reference code that actually exists in the codebase.
• Plans describe WHAT and WHY, not HOW at the code level. Include: file paths, function names, behavioral specs, test assertions, patterns to follow (reference existing files by path), state transitions. Do NOT include: implementation code blocks, ready-to-paste TypeScript/TSX, full function bodies. The implementer (plan-implement workers) writes all code — your job is architecture and specification. Exception: short one-liners for surgical changes (e.g., "add if (!session.x) check after the existing !session.y check") are fine.
• Flag migration-relevant fixes — If the fix changes spreadsheet schema, renames columns, changes folder structure, or renames env vars, add a note in the fix plan: "Migration note: [what production data is affected and how to migrate]". The plan MUST include a migration strategy (e.g., startup detection of old format + automatic migration). The implementer will log this in MIGRATIONS.md.
• For prompt issues, test multiple variations before recommending changes
• Create Linear issues in Todo state for each fix task
• Include Linear issue links in PLANS.md

11. Scope Boundaries

This skill is specifically for:

• Investigating reported bugs and errors
• Creating structured fix plans with TDD approach
• Creating Linear issues for tracking

This skill is NOT for:

• Actually implementing fixes (use plan-implement for that)
• Adding new features (use plan-backlog or add-to-backlog)
• Code reviews (use code-audit)
• General investigation without a fix intent (use investigate)
• Refactoring (create a separate task)

12. Termination

Follow the termination procedure in references/plans-template.md: output the Plan Summary, then create branch, commit (no Co-Authored-By tags), and push.

If chained from investigate skill, reference the investigation findings and note any additional evidence found during planning.

Do not ask follow-up questions. Do not offer to implement. Output the summary and stop.