capability-diagnostic
Diagnose agent failures by identifying missing capabilities. Use when an agent fails a task, produces wrong output, or needs escalation. Provides a decision tree for failure analysis.
npx skills add majiayu000/claude-skill-registry --skill capability-diagnostic --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Capability Diagnostic ## When to Use Run this diagnostic when an agent: - Fails a task (test failures, wrong output, incomplete work) - Produces output that doesn't match the expected schema - Gets blocked by enforcement hooks repeatedly - Takes significantly longer than expected on a straightforward task ## Failure Analysis Decision Tree ### Step 1: Did the agent have the right tools? - Check `allowed-tools` in agent spec (if any) - Check if enforcement hooks blocked required tool calls - **Fix**: Add missing tools to agent spec, or adjust hook configuration ### Step 2: Did the agent have the right context? - Check which skills were preloaded (agent spec `skills` field) - Was the task specification complete and unambiguous? - Did the agent need information from files it didn't read? - **Fix**: Add missing skills to agent spec, improve task prompt ### Step 3: Did the agent have sufficient model capability? - Haiku struggles with: design decisions, cross-module reasoning, ambiguous specs - Sonnet struggles with: subtle bugs, architecture-sensitive changes, performance optimization - Opus handles: complex reasoning, cross-cutting concerns, deep analysis - **Fix**: Escalate to next
- When to Use
- Failure Analysis Decision Tree
- Step 1: Did the agent have the right tools?
- Step 2: Did the agent have the right context?
- Step 3: Did the agent have sufficient model capability?
- Step 4: Was the task specification ambiguous?
- Step 5: Was it an infrastructure issue?
- Output Format
- Common Patterns
What does the capability-diagnostic skill do?
Diagnose agent failures by identifying missing capabilities. Use when an agent fails a task, produces wrong output, or needs escalation. Provides a decision tree for failure analysis.
How do I install it?
Run `npx skills add majiayu000/claude-skill-registry --skill capability-diagnostic --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From majiayu000/claude-skill-registry, a repository with 534 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.