openhonest/umbra

Overview

Umbra is a code auditor that identifies structural blind spots in a test suite, reporting areas that tests are unable to reach. For each gap it finds, it generates a real failing test to demonstrate the missing coverage. This helps developers see concrete evidence of untested code paths.

Best for

Best for
Developers who want to strengthen their test suites by exposing and proving untested code paths.

Use cases

• Identify untested code paths and branches
• Generate failing tests to expose coverage gaps
• Audit test suites for structural blind spots

Notes

Umbra is a code auditor that identifies structural blind spots in a test suite, reporting areas that tests are unable to reach. For each gap it finds, it generates a real failing test to demonstrate the missing coverage. This helps developers see concrete evidence of untested code paths.

3 stars on GitHub. Last updated 2026-08-12. Licensed Apache-2.0.

Use cases

• Identify untested code paths and branches
• Generate failing tests to expose coverage gaps
• Audit test suites for structural blind spots

Pros

• Provides concrete proof of gaps via failing tests
• Focuses on structural limitations rather than simple line coverage
• Helps prioritize test writing efforts by showing what is missing

Cons

• Generated tests are intentionally failing and require manual review
• Only detects structural gaps, not logical or semantic errors
• Requires an existing test suite to analyze

Indexed from awesome-mcp-servers-punkpeye and enriched against its public facts.