Conciseness

The body is dense factual routing tables and priority chains Claude cannot know, with no padding or basic-concept explanation; excess is minor — env keys are duplicated between the Source Overview table and the Ban-Risk Notes, and the time-sensitive mootdx retirement note ("retired 2026-10") sits inline rather than in a deprecated section. Not 5 because those redundancies could be trimmed; not 3 because almost every row carries decision-relevant information.

Actionability

Fully concrete guidance throughout: exact tool names (get_market_data, get_fund_flow, cross_validate with its {source: value, ...} call shape), exact env keys, explicit per-market priority chains, symbol formats with examples, and the actionable default "Use source: 'auto'". For an instruction-only routing skill this is copy-paste-ready and covers the common cases.

Workflow Clarity

A two-scenario decision tree with numbered steps and real error-recovery loops (report missing keys rather than failing silently, throttle/timeout → same-market fallback, envelope errors never aborting a batch), plus an explicit data-verification discipline. Not 5 because the workflow is distributed across several sections rather than one coherent sequence with validation checkpoints inline.

Progressive Disclosure

No bundle files exist and all ~175 lines — the full source registry, capability-to-tool table, and symbol format reference — live inline in SKILL.md. Sections and tables are well organized, but this volume of reference material clearly belongs in separate one-level-deep files. Matches anchor 3 (content that should be separate is inline) rather than 4, since nothing is split out; not 2 because headers and tables keep it navigable.

Specificity

Lists several concrete actions — "pick the best available source/tool", "honour auth (env) requirements", "avoid ban-risk providers" — with minor coverage gaps since narrower capabilities (fund flow, filings, macro series) go unmentioned. Not 3 because it goes beyond 1-2 actions; not 5 because the action list is not comprehensive.

Completeness

Both parts are explicit: an equivalent "Use when" clause ("Load this skill BEFORE any backtest, data-fetch, or research task") plus a three-action "what". Not 5 because "The single ROUTER for every data need" states the role through a metaphor rather than plainly naming the mapping capability it performs.

Trigger Term Quality

Natural domain keywords like "backtest", "data-fetch", "research task", "source/tool", and "auth" are present and would be said by users of this domain. Not 5 because common variations such as "market data", "price data", "OHLCV", or "fetch data" are missing.

Distinctiveness Conflict Risk

The router positioning and distinctive phrases like "avoid ban-risk providers" carve a clear niche with only minor overlap risk against the per-source sibling skills it routes to. Not 3 since it is deliberately the upstream entry point; not 5 since "every data need" / "any ... task" is a broad universal claim.