Analyze CI Failure Logs

Analyze CI Failure Logs

Parse CI failure logs to identify root causes and categorize errors.

When to Use

• CI pipeline fails and you need to understand why
• Analyzing test failure logs from GitHub Actions
• Extracting error messages from build artifacts
• Identifying patterns in recurring failures
• Determining if failure is environmental or code-related

Quick Reference

# Download CI logs from artifact
gh run download <run-id> -D /​tmp/​ci-logs

# Extract from workflow run
gh run view <run-id> --log > /​tmp/​ci-output.log

# Grep for error patterns
grep -i "error\|failed\|panic\|exception" /​tmp/​ci-output.log

# Get summary of failures
tail -100 /​tmp/​ci-output.log | grep -A 5 "FAILED\|ERROR"

Workflow

1. Collect logs: Download CI artifacts or view workflow run output
2. Extract errors: Filter for error patterns (FAILED, ERROR, PANIC, exception)
3. Identify type: Categorize error (compilation, test, timeout, dependency, etc.)
4. Find root cause: Trace back to source (line numbers, stack traces)
5. Check context: Compare with recent changes in PR
6. Create summary: Report findings with actionable next steps

Log Analysis Patterns

Compilation Errors:

• Look for: error:, undefined, type mismatch
• Check: Mojo syntax, imports, type annotations

Test Failures:

• Look for: FAILED, AssertionError, ValueError
• Check: Test logic, expected vs actual values

Timeout Issues:

• Look for: timeout, timed out, hanging
• Check: Long-running loops, infinite recursion

Dependency Issues:

• Look for: not found, import failed, version conflict
• Check: Package versions, environment setup

Environmental Issues:

• Look for: permission denied, out of memory, disk full
• Check: Resource limits, configuration

Output Format

Provide analysis with:

1. Error Category - Type of failure (compilation, test, timeout, dependency, environmental)
2. Root Cause - What line/​code caused the failure
3. Context - Full error message and stack trace
4. Related Changes - Which PR changes might have caused it
5. Remediation - Recommended fix or investigation steps

Error Handling

References

• GitHub Actions documentation: workflow logs and artifacts
• CLAUDE.md: zero-warnings policy and standards
• See fix-ci-failures skill for implementing fixes