Conciseness

The body largely avoids concept explanations Claude already knows and uses dense tables rather than prose, but at ~870 lines / ~45KB it inlines substantial reference material — full tool-endpoint parameter tables with five curl examples, MCP tool parameter tables for every endpoint, and a complete per-script catalog — that belongs in the existing references. This matches 'Mostly efficient but includes some unnecessary explanation or could be tightened' rather than score 4, because the trimmable inline reference content is more than minor.

Actionability

Nearly every task row gives a copy-paste-ready command with concrete arguments (e.g. 'opensea nfts get ethereum 0xbc4c... 1234'), curl examples include headers, the key-resolution fallback is a complete executable bash block, and SDK code is runnable TypeScript. This matches the score-5 anchor 'Fully executable; copy-paste ready code or commands; specific examples cover the common cases'.

Workflow Clarity

The API key resolution section is an explicitly ordered 4-step flow with checkpoints ('Save immediately after fetching... before making your API call') and a feedback loop for stale keys (401/403 → re-fetch with --force). Batch/destructive operations are covered by a pre-bulk-operation checklist with a verify-first request and limit=1 test, and the error table gives per-status retry actions. This matches the score-5 anchor with explicit validation steps, error-recovery loops, and a checklist.

Progressive Disclosure

Bundle structure is good: references/authentication.md, rest-api.md, and stream-api.md all exist, are clearly signaled at point of use ('Read the wallet authentication reference before acting as a wallet'), and are one level deep; scripts are cataloged per directory. It falls short of score 5 because sizeable reference-grade content (the ERC-8257 tool endpoint parameter tables and curl examples, and the per-endpoint MCP parameter documentation) is inlined in SKILL.md rather than split into the existing references — matching 'Good structure... references mostly clear; minor organization gaps'.

Specificity

The description names concrete tools ("via the official CLI, SDK, MCP server, or shell scripts") and enumerates many specific actions — "floor prices, collection stats, NFT details, token data, trending collections, drops, events, search, favorites, profile and collection settings" — which matches the anchor 'Lists multiple specific concrete actions; comprehensive coverage'. It sits above the score-4 anchor because coverage of the skill's operations is near-exhaustive rather than having minor gaps.

Completeness

The 'what' is clear and concrete, but there is no positive 'Use when...' trigger clause — only negative routing ("For trading use opensea-marketplace, for token swaps use opensea-swaps"), which tells when NOT to use it but only weakly implies when to use it. The judging guideline that a missing 'Use when' clause or equivalent explicit trigger guidance caps completeness at 3 applies; it cannot score 4, which requires both 'what' and an explicit 'when'.

Trigger Term Quality

Phrases like "floor prices", "collection stats", "trending collections", "drops", "events", and "search" are terms users would naturally say when needing OpenSea data. It falls short of the score-5 anchor ('comprehensive coverage of natural terms including synonyms') because common user phrasings like "mint", "watchlist", "NFT floor price", and "P&L/portolio" are absent.

Distinctiveness Conflict Risk

It occupies a clear niche ("OpenSea marketplace data") and explicitly hands off adjacent needs to sibling skills ("For trading use opensea-marketplace, for token swaps use opensea-swaps"), minimizing the chance of triggering for the wrong skill. This matches the score-5 anchor 'Clear niche with distinct triggers; minimal conflict risk'.