Enhancement: Add build comparison and diff tools for Workers Builds

[Scarmonit]

Problem

When managing Workers Builds, developers often need to:

1. Compare builds - Understand what changed between successful and failed builds
2. Track configuration changes - See how build/deploy commands evolved over time
3. Debug regressions - Identify when specific issues were introduced
4. Audit deployments - Track changes for compliance and debugging

Currently, the MCP server provides tools to view individual builds, but lacks comparison capabilities.

Proposed Enhancement

Add Build Comparison Tool

Tool Name: workers_builds_compare_builds

Functionality:

• Compare two builds by UUID
• Show differences in:
  • Build commands
  • Deploy commands
  • Build duration
  • Success/failure status
  • Error messages (if applicable)
  • Timestamps

Example Usage:

Compare build abc-123 with build def-456

Output Format:

{
  "build_a": { "uuid": "abc-123", "status": "success", ... },
  "build_b": { "uuid": "def-456", "status": "failure", ... },
  "differences": {
    "status_changed": true,
    "command_changed": false,
    "duration_delta": "+15s",
    "new_errors": ["Error message here"]
  }
}

Add Build History Summary Tool

Tool Name: workers_builds_get_summary

Functionality:

• Get aggregate statistics for a worker
• Success/failure rates
• Average build duration
• Common errors
• Recent trends

Example Usage:

Show me a summary of builds for my-worker over the last 7 days

Enhanced Prompt Examples

With these new tools:

• Compare my last successful build with the failed build
• What changed between build abc-123 and def-456?
• Show me build success rate for frontend-app this week
• What are the most common build errors for my-worker?
• When did build duration start increasing for api-worker?

Benefits

• Faster debugging - Quickly identify what changed between builds
• Better insights - Understand build patterns and trends
• Proactive monitoring - Catch regressions early
• Compliance - Better audit trail for deployments

Implementation Notes

• Should work with existing workers_builds_set_active_worker pattern
• Consider pagination for large datasets
• Cache comparison results for performance
• Include error log diffs if logs differ significantly

Related Functionality

• Complements existing workers_builds_get_build tool
• Works alongside workers_builds_list_builds for context
• Could integrate with monitoring/alerting tools

Priority

Medium-High - This would significantly enhance debugging capabilities and provide valuable insights for CI/CD workflows.

This enhancement makes the MCP server more powerful for understanding build history and troubleshooting issues.