From nexus
Guides root-cause analysis of failures in CI/CD, tests, runtime, deployment, and tooling. Outputs RCA, narrowest fix, verification, and prevention.
How this skill is triggered — by the user, by Claude, or both
Slash command
/nexus:debuggingThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
Route to the correct sub-guide and follow it end-to-end.
Route to the correct sub-guide and follow it end-to-end.
skills/debugging/ci-cd.md, skills/debugging/codebase.md, skills/debugging/frameworks.mdskills/debugging/common.mdPick exactly one track:
| Track | Failure origin | Sub-guide |
|---|---|---|
| CI/CD | GitHub Actions, Jenkins, CircleCI, or deployment pipeline log | ci-cd.md |
| Codebase | Failing test, runtime exception, or regression in application code | codebase.md |
| Framework | Django, FastAPI, Bazel, or other tooling misbehavior | frameworks.md |
If unsure: ask "Is the failure in pipeline logs, app code, or a framework?"
Before reading the sub-guide, collect:
Read the appropriate sub-guide. Follow its steps in order. Do not skip steps.
Read common.md for shared output format and checklists.
If the error is framework-specific or tool-specific:
"<exact error message>" <tool-name> <version> — use exact error text## Debug Report
**Track:** [CI/CD | Codebase | Framework]
**Root Cause:** [one sentence — specific, not "something went wrong"]
**Fix:** [exact command or minimal code diff]
**Verification:** [command to run to confirm fix]
**Prevention:** [what change stops this from recurring]
Input: User pastes GitHub Actions log:
ModuleNotFoundError: No module named 'pydantic'
Error: Process completed with exit code 1.
Step 1: Track = CI/CD (failure in pipeline)
Step 2: Error = ModuleNotFoundError: No module named 'pydantic'; changed = recent dependency PR; env = GitHub Actions Ubuntu 22.04
Step 4: Search "ModuleNotFoundError: No module named 'pydantic'" github actions → find pydantic missing from requirements.txt
Output:
## Debug Report
Track: CI/CD
Root Cause: pydantic installed locally but not in requirements.txt — CI builds from scratch so it's absent
Fix: pip freeze | grep pydantic >> requirements.txt && git add requirements.txt && git commit -m "fix: add pydantic to requirements"
Verification: Re-run the failing GitHub Actions job — confirm it passes
Prevention: Add a CI step that runs `pip check` after install to catch missing transitive deps
git bisect if the commit is not obvious.npx claudepluginhub aayushostwal/nexus --plugin nexusGuides systematic root-cause debugging when tests fail, builds break, or unexpected errors occur. Provides a structured triage checklist to preserve evidence, localize, and fix issues instead of guessing.
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes