Conciseness

The ~55-line body assumes Claude's competence throughout: every sentence is a behavioral directive ('Do not publish a UNRESOLVED diagnosis as fact', 'Do not create a separate local RCA document. The GitHub issue or comment is the artifact.') with zero concept explanation or padding. This matches the 5 anchor (lean, every token earns its place); there is nothing to trim to reach 4 or below.

Actionability

Although it is an instruction-only skill with no code (not penalized per the scoring notes), the guidance is fully executable: an explicit decision tree ('One clear match → use it', 'Several plausible matches → ask the user', 'No clear match → plan to create an issue'), an enumerated list of required RCA outputs, per-case publication behavior, and a concrete verification step ('Read the created or updated issue back to verify the content'). It matches the 5 anchor's copy-paste-ready specificity for an orchestration skill; 4 would require minor gaps, and none are evident.

Workflow Clarity

The four numbered stages (resolve target → run root-cause analysis → reconcile duplicates → publish) are clearly sequenced with explicit validation checkpoints: UNRESOLVED/CCONDITIONAL gating before publication, re-checking duplicate candidates against the diagnosed cause, stopping before publication when GitHub access is missing, and a read-back verification of the published artifact. This matches the 5 anchor (explicit validation, feedback loops); the 4 anchor would require missing checkpoints, and none are.

Progressive Disclosure

The skill is a self-contained workflow with no bundle files and no content that belongs in separate references; per the simple-skill scoring note, well-organized sections suffice. Sections are cleanly numbered with descriptive headings and easy in-file navigation, matching the 5 anchor's easy-navigation standard rather than the 4 anchor's 'minor organization gaps'.

Specificity

The description lists multiple concrete actions — 'Diagnoses a bug, error, stack trace, regression, or unexplained behavior', 'publishes the evidence-backed root cause to GitHub', 'commenting on the matching open issue or creating one when none exists' — with comprehensive coverage of the skill's diagnostic and publication behavior in third-person voice. It clearly matches the 5 anchor (multiple specific concrete actions, comprehensive) rather than 4, which requires minor gaps in coverage.

Completeness

It explicitly answers 'what' (diagnose and publish the evidence-backed root cause, with the default publication behavior stated) and 'when' ('Use when the user says "debug this", "find the root cause", provides a bug report or stack trace, asks to investigate a GitHub issue, or invokes $prp-debug'). Both halves are explicit with concrete trigger phrases, matching the 5 anchor exactly.

Trigger Term Quality

It quotes natural user phrases ('debug this', 'find the root cause', 'investigate a GitHub issue') and covers synonyms across the domain — bug, error, stack trace, regression, unexplained behavior, bug report — plus the explicit invocation name $prp-debug. Comprehensive natural-term coverage fits the 5 anchor; nothing common is missing.

Distinctiveness Conflict Risk

The niche is distinct — root-cause diagnosis with durable GitHub publication, explicitly scoped away from implementing the fix — but the trigger 'debug this' is a very common phrase that could also fire for general debugging/verify skills, so it sits between the 4 anchor (mostly distinct, minor overlap risk with closely related skills) and the 5 anchor (minimal conflict risk). It is above the midpoint because the publication focus and $prp-debug invocation clearly carve the niche.