Conciseness

At ~690 lines the body states the same core rules four to five times: the {{}} brace rule appears in "Expression Format", "Validation Rules" #1/#4, "Common Mistakes" quick-fix table, "Best Practices" Do/Don't, and "Summary"; the webhook `.body` rule and case-sensitive node names repeat similarly. "Expression Helpers/Available Methods" and "Data Type Handling" list standard JS (`.toLowerCase()`, `.split()`, `.map()`, ternaries, dot vs bracket notation) Claude already knows. Below anchor 3 because the duplication is extensive, though not anchor 1 since substantial high-value non-obvious content ($jmespath quoting table, silent-null runtime behavior) is interwoven.

Actionability

Copy-paste-ready wrong-vs-right pairs (❌ `{{$json.name}}` / ✅ `{{$json.body.name}}`), exact error messages ("expected two arguments (Object, string)"), a tested $jmespath table, a debugging wrapper snippet, a concrete MCP removal sequence (removeConnection → addConnection → patchNodeField → removeNode), and worked examples covering the common cases. Fully executable with no gaps.

Workflow Clarity

The "transform gatekeeper" is an explicitly ordered decision procedure ("walk this order and stop at the first that fits", numbered 1-4) and the debugging section sequences verification (editor preview → check output for `null` → temporary try/catch wrapper) with a recovery loop. Not 5: checkpoints are scattered across sections rather than consolidated into one validated workflow, and the Set-node removal procedure states steps but no verify step after the patch. This is not a destructive/batch skill, so no cap applies.

Progressive Disclosure

No bundle files exist — neither references/ nor the referenced COMMON_MISTAKES.md and EXAMPLES.md are present, so both "See [COMMON_MISTAKES.md]" and "See [EXAMPLES.md]" links are dangling. Meanwhile the body inlines ~3 full worked examples in "Working Examples" and a quick-fix mistake table, i.e. the very content the missing files would hold. Falls below anchor 3 (references present but organization imperfect) because navigation to the referenced files actually fails; matches anchor 2's clause of content that belongs in separate files being inlined.

Specificity

"Validate n8n expression syntax and fix common errors" names the domain and two concrete actions, but the capability list stops there — the writing/guide role the body actually serves is never stated as an action. It sits between anchor 3 (1-2 concrete actions, not comprehensive) and anchor 4 (several specific actions); the rest of the description is trigger clauses, not capabilities, so 3 fits best.

Completeness

Explicitly answers both questions: what ("Validate n8n expression syntax and fix common errors") and when, with three concrete trigger clauses ("Use when writing n8n expressions...", "Use this skill whenever configuring node fields that reference data from previous nodes", "Also use when asked whether a complex expression hurts performance"). Matches the anchor-5 example structure.

Trigger Term Quality

Comprehensive natural phrasing users would actually say: "writing n8n expressions", "using {{}} syntax", "troubleshooting expression errors", "mapping data between nodes", "referencing webhook data", and "whether a complex expression hurts performance" — including variable names ($json/$node) users literally type. No relevant synonyms are missing; there are no file extensions in this domain.

Distinctiveness Conflict Risk

Clear niche (n8n expression syntax) with domain-specific triggers that few other skills would claim. Minor overlap risk remains: the performance clause and "mapping data between nodes" could collide with sibling n8n workflow/code skills mentioned in the body's Related Skills. Not 5 because that overlap is plausible, not minimal.