Lists multiple specific concrete actions: appending entries to LESSONS-LEARNED.md via a specific CLI tool, searching past lessons for matching errors, and proposing skill updates when retry patterns exceed thresholds.

Clearly answers both 'what' (appends entries, searches past lessons, proposes skill updates) and 'when' with an explicit 'Use when...' clause covering four distinct trigger scenarios.

Includes natural trigger terms users/Claude would encounter: 'LESSONS-LEARNED.md', 'task failures', 'retrospective insights', 'retry succeeds', 'lesson', 'errors'. These cover the scenarios where this skill would be relevant.

Highly distinctive with specific references to LESSONS-LEARNED.md, the opencastle lesson CLI, and retry pattern thresholds. Unlikely to conflict with other skills due to its narrow, well-defined niche.

Every section is lean and purposeful. No unnecessary explanations of what lessons-learned files are or why documentation matters. The anti-patterns section is terse bullet points, and the CLI example is copy-paste ready without preamble.

Provides a fully executable CLI command with all flags, a concrete search example using ripgrep, and a verification command (tail -1). The hard gate on using the CLI vs direct editing is a clear, specific constraint.

The 6-step workflow is clearly sequenced with explicit validation at step 5 (verify the entry, re-run if malformed) and a feedback loop for retries at step 3. The progression from search → attempt → failure handling → success recording → verification → propagation is well-structured.

Category/severity tables are appropriately moved to a separate LESSON-CATEGORIES.md with a clear reference. The agent-memory skill is signaled as a separate concern. The skill stays focused on its core purpose without inlining reference material.