Conciseness

Every token earns its place: the intro conveys non-obvious facts (the spec is "deeply nested JSON:API schemas with repeated unions and byte-identical error envelopes", "**You never handle API tokens**") rather than concepts Claude already knows, and each workflow step is 2-3 lines with an executable command. Not 4: no identifiable passage of over-explanation to trim.

Actionability

Fully executable, copy-paste-ready commands throughout: "python3 scripts/tessl_api_discover.py search install policy", "show post /v1/install/policy/evaluate --expand", and a complete "tessl api -X POST ... --input - <<'JSON'" invocation with a JSON body. Not 4: concrete examples cover the common cases with real paths and no gaps.

Workflow Clarity

The 5-step workflow is clearly sequenced with feedback branches ("If keyword search misses, search by property", "if your path is ambiguous the script lists the candidates", network-down cache fallback), but there are minor validation gaps: no guidance when both search modes miss, and no post-call verification of the API response. Not 5: explicit validation steps after the call are absent; not 3: the sequence and most checkpoints are present.

Progressive Disclosure

SKILL.md is a well-organized overview (intro, The helper, Workflow, Notes) with the heavy lifting correctly pushed into the one-level-deep bundle file "scripts/tessl_api_discover.py", which exists. Not 4: no bulk detail is inlined in the body that belongs in a separate file; navigation is trivial.

Specificity

Lists multiple specific concrete actions — "Find and call Tessl API endpoints", "discover which endpoint does something", "to learn an endpoint's path, parameters, request body shape, or response shape" — with comprehensive coverage of the skill's capabilities. Not 4: coverage has no minor gaps; every action the skill performs is named.

Completeness

Explicitly answers both questions: what ("Find and call Tessl API endpoints") and when ("Use this WHENEVER you need a Tessl REST API endpoint — to discover... or to actually call"). Not 4: the when-clause is explicit and enumerates concrete trigger scenarios, matching the top anchor exactly.

Trigger Term Quality

Natural terms users would say are comprehensively covered: "Tessl API", "REST API endpoint", "call the Tessl API", "endpoint", plus the concrete file name "`openapi.json`". Not 4: no natural variation of the trigger phrasing for this domain is missing.

Distinctiveness Conflict Risk

Clear niche scoped to a named product (Tessl) with distinct triggers and explicit disambiguation ("Reach for this skill INSTEAD OF reading the raw `openapi.json` spec"), minimizing overlap with generic API/OpenAPI skills. Not 4: the niche is fully distinct, not just mostly.