Conciseness

The body is mostly efficient structurally, but the 'Extended thinking' paragraph restates the workflow in padded, conceptual prose that adds no actionable value and could be trimmed.

Actionability

Each phase provides concrete Task prompts naming specific tools (k6/Gatling/Artillery, DataDog/New Relic, Redis/Memcached) and subagent types, giving mostly executable guidance with minor gaps around verifying those agents exist.

Workflow Clarity

A clearly sequenced 5-phase process exists, but destructive/batch operations (production load testing, DB/backend changes) lack explicit validate-before-proceeding checkpoints, capping this at 3 per the rubric.

Progressive Disclosure

Sections are well-organized, but the skill is monolithic: all 13 step prompts, configuration, and success criteria are inlined with no external reference files despite being long enough to benefit from them.

Specificity

Names several concrete action areas — 'profiling, observability, and backend/frontend tuning' — though 'tuning' is somewhat generic, leaving minor coverage gaps.

Completeness

Clearly states the 'what' (optimize end-to-end performance via profiling/observability/tuning) and an explicit 'Use when coordinating performance optimization across the stack' clause, though the 'when' is broad rather than trigger-specific.

Trigger Term Quality

Includes natural phrases a user would say ('application performance', 'performance optimization', 'across the stack') but misses common synonyms like 'speed up' or 'latency'.

Distinctiveness Conflict Risk

The end-to-end stack-wide performance optimization niche is mostly distinct, with only minor overlap risk against generic optimization or single-layer tuning skills.