opensea-marketplace

Buy and sell NFTs through OpenSea on EVM chains and Solana. Fulfill listings, accept or create offers, cancel orders, make cross-chain purchases, and sweep listings. Requires wallet signing; for read-only queries use opensea-api instead.

Quality

85%

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Securityby

Medium

Suggest reviewing before use

Quality

Content

92%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The content body is a strong example of a marketplace-execution skill: fully executable commands for every core workflow, explicit transaction-safety checkpoints for destructive and batch operations, and a clean overview that pushes detail into two real, well-organized reference files. The only notable inefficiencies are minor duplication of the description and the native-token mint rule.

Dimension	Reasoning	Score
Conciseness	The body is lean — script tables, concrete commands, and pointed references with no explanations of concepts Claude already knows — but the intro paragraph repeats the frontmatter description verbatim and the native-token address rule appears twice ("Creating listings/offers" and "Solana order actions"), so it is not perfectly tight.	4 / 5
Actionability	Every common case (buy, sell, cross-chain, sweep, create offer, cancel) has copy-paste-ready commands in both script and CLI forms, and a full script-signature table; all seven referenced scripts exist in scripts/. Matches the fully-executable, common-cases-covered anchor.	5 / 5
Workflow Clarity	Buy/sell/cross-chain flows are numbered, and destructive/batch onchain operations get explicit validation checkpoints ("Always verify fulfillment data before signing. Check that the returned `to` address, `value`, and `data` fields", "Check order expiry", "verify each succeeds before proceeding") plus feedback loops (404 → re-query, 500 → retry with backoff), satisfying the batch-operation cap and matching the top anchor.	5 / 5
Progressive Disclosure	A clear overview with well-signaled, one-level-deep references: both referenced files exist in references/, and section-level pointers ("references/marketplace-api.md → Fulfilling ERC20-denominated listings", "→ Solana transaction submission") resolve to real headers in that file, with cross-skill handoffs clearly labeled.	5 / 5
	Total	19 / 20 Passed

Description

75%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A highly specific, distinctive description that names concrete capabilities and cleanly hands off read-only queries to the sibling API skill. Its one real weakness is the absence of an explicit positive trigger clause ("Use when buying or selling NFTs…"), leaving the "when to use it" only implied by the negative contrast.

Suggestions

Add an explicit trigger clause, e.g. "Use when buying, selling, or trading NFTs, fulfilling listings or offers, or sweeping multiple listings on OpenSea."

Include natural synonyms and chain names users actually say — e.g. "Ethereum", "Polygon", "Base", "Solana", "purchase NFTs", "trade NFTs" — to improve trigger-term coverage beyond "EVM chains" jargon.

Dimension	Reasoning	Score
Specificity	"Fulfill listings, accept or create offers, cancel orders, make cross-chain purchases, and sweep listings" enumerates multiple specific concrete actions with comprehensive coverage of the domain, matching the top anchor rather than the minor-gaps anchor below it.	5 / 5
Completeness	The "what" is explicit and concrete, but there is no "Use when…" clause or equivalent positive trigger guidance; the "when" is only weakly implied via the negative handoff "for read-only queries use opensea-api instead". Per the judging guideline, a missing explicit trigger clause caps completeness at 3, and anchor 4 would require an actual (if imperfect) "when" statement.	3 / 5
Trigger Term Quality	Natural phrases users would say are present ("buy and sell NFTs", "listings", "offers", "cross-chain", "sweep listings"), but "EVM chains" is jargon where users would more naturally say "Ethereum", and synonyms like "trade" or "purchase NFTs" are missing — good coverage with a few natural terms absent, so between anchors 4 and 5, closer to 4.	4 / 5
Distinctiveness Conflict Risk	The description carves a clear niche — trade execution requiring wallet signing — and explicitly disambiguates from the sibling skill ("for read-only queries use opensea-api instead"), giving minimal conflict risk, matching the distinct-triggers anchor.	5 / 5
	Total	17 / 20 Passed

Validation

87%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 14 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning
relative_links	Relative link issues: 2 suspicious	Warning

	Total	14 / 16 Passed

Repository: ProjectOpenSea/opensea-skill
Path: opensea-marketplace/SKILL.md
Commit: b0fa63f

Reviewed: 6 days ago

Table of Contents

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