---
name: doublecheck
description: "Thorough review and verification of all code changes. Use when the user says /doublecheck, 'double check', 'review your work', 'verify changes', or asks to make sure nothing was missed after a set of code changes. Traces through all modifications, validates correctness, checks for bugs, and builds the solution."
---

# Double Check

Thoroughly review and verify all code changes made in this session.

## Process

1. **Trace through every change**: Re-read each modified file. Walk through the logic path from entry point to exit for every change. Confirm each change matches the original request.

2. **Verify completeness**: Compare what was requested against what was implemented. Flag anything missing or incomplete.

3. **Check for bugs and issues**:
   - Thread safety problems (shared mutable state, race conditions)
   - Memory leaks (undisposed resources, event handler leaks, missing `using` statements)
   - Async issues (missing `await`, deadlocks, fire-and-forget without error handling)
   - Performance issues (N+1 queries, unnecessary allocations, blocking calls in async paths)
   - Null reference risks
   - Off-by-one errors
   - Error handling gaps

4. **Check for linter errors and warnings**: Review code style, unused imports, unused variables, naming conventions, and any compiler warnings. Fix any found issues whether pre-existing or newly introduced.

5. **Build the solution**: Run the build once all changes are finalized. Fix any errors or warnings that appear.