Conciseness

The body is lean with no filler and no explanation of concepts Claude already knows; the Trigger/Fix/Why structure earns its tokens. It misses score 5 because it embeds time-sensitive version claims — 'actions/setup-go@v6 sets GOTOOLCHAIN=local', 'A range such as go-version: 1.26.x', 'Older setup-go versions keep GOTOOLCHAIN=auto', and a concrete 1.26.10/1.26.9 error example — that are not quarantined in an 'old patterns'/'deprecated' section, per the guideline penalizing version-specific information in the main flow.

Actionability

The Fix section is a complete, copy-paste-ready YAML snippet ('uses: actions/setup-go@v6 / with: go-version-file: go.mod') that directly resolves the stated trigger, matching the 'fully executable; copy-paste ready' anchor. The Why section adds the non-obvious factual detail (GOTOOLCHAIN behavior differences across setup-go versions) that makes the fix trustworthy rather than magical.

Workflow Clarity

This is a simple, single-purpose skill and the single action is unambiguous — the scoring notes allow a 5 in that case. Trigger, Fix, and Why are clearly separated; the fix is a one-line configuration change, not a destructive or batch operation, so no validation checkpoint is required.

Progressive Disclosure

The skill is under 20 lines with no need for external references (verified: no references/, scripts/, or assets/ directories exist), and the content is organized into clear Trigger/Fix/Why sections. Per the guideline for skills under 50 lines with no need for external references, this matches the top anchor for a self-contained skill.

Specificity

The description names the domain ('go directive in go.mod', 'CI') and one concrete action ('Make CI install the go.mod version'), but does not enumerate the specific mechanisms (e.g., setup-go with go-version-file) or multiple capability actions. It fits the 'names domain and 1-2 concrete actions, but not comprehensive' anchor — above score 2 because the action is genuinely concrete, below score 4 because coverage of what the skill actually does is a single terse outcome statement.

Completeness

'When' is explicit and concrete (two triggers, one an exact error message), and 'what' is present ('Make CI install the go.mod version'), so both boxes are checked as in the score-4 anchor. It falls short of score 5 because the 'what' is a single high-level outcome statement that omits the concrete fix mechanism (setup-go/go-version-file), leaving the what-side less explicit than the when-side.

Trigger Term Quality

It includes the natural terms a user would say or paste in this niche: 'raising the go directive', 'go.mod', 'CI fails', and the verbatim error string 'go.mod requires go >= X (running go Y; GOTOOLCHAIN=local)' — including the GOTOOLCHAIN detail and file name. Coverage is comprehensive for this domain (synonym 'raising the go directive' for 'bump go version', the literal CI error text), matching the top anchor rather than the 'a few natural terms missing' anchor at 4.

Distinctiveness Conflict Risk

The trigger is a narrow, well-defined niche — the go.mod go directive plus a specific CI toolchain error — with distinct trigger phrases that no other plausible skill would claim, matching the 'clear niche with distinct triggers; minimal conflict risk' anchor. It is clearly above score 4, which requires only minor overlap risk with closely related skills.