opensea-marketplace

Buy and sell NFTs on OpenSea's Seaport marketplace. Fulfill listings, accept offers, create new orders, cross-chain purchases, and sweep multiple listings. Requires wallet signing; for read-only queries use opensea-api instead.

Quality

84%

Does it follow best practices?

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Securityby

Medium

Suggest reviewing before use

Quality

Content

85%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 is well-structured, actionable, and uses progressive disclosure effectively with real bundle files. It is near the top of the rubric; the main lever is tightening the inline ERC20 explanation and adding an explicit validate-before-sign checkpoint to the batch sweep workflow.

Suggestions

Add an explicit validation step into the cross-chain/sweep numbered workflow (e.g. 'verify each returned transaction's to/value/data before signing; stop and re-query on 404') to close the feedback loop for this destructive batch operation.

Trim the inline ERC20 conduit/approval explanation and lean more on the reference ("See references/marketplace-api.md → Fulfilling ERC20-denominated listings") to reduce token weight while keeping the key 'never assume 18 decimals' warning.

Dimension	Reasoning	Score
Conciseness	The body is largely lean and assumes competence, but the ERC20 subsection explains mechanism (transferFrom, conduit resolution) at length that could be deferred to the referenced file; minor trimmable over-explanation.	4 / 5
Actionability	Copy-paste-ready bash commands and a script-arg table cover the common buy/sell/cross-chain/sweep cases with concrete, executable invocations and specific argument placeholders.	5 / 5
Workflow Clarity	Each workflow is a numbered sequence with concrete commands and an error-handling table plus transaction-safety checkpoints, but the destructive batch/sweep path lacks an explicit validate-before-sign feedback loop tying the checkpoints into the sweep steps.	4 / 5
Progressive Disclosure	SKILL.md is a concise overview with clearly signaled one-level-deep references (references/marketplace-api.md, references/seaport.md) and bundled scripts; all referenced files exist and the deep ERC20/Seaport detail is correctly offloaded to the references.	5 / 5
	Total	18 / 20 Passed

Description

83%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.

The description is specific and clearly distinguishes the skill via an explicit scope-out handoff. It would benefit from a forward "Use when..." trigger phrase and a few more natural synonyms to push completeness and trigger-term quality to 5.

Suggestions

Add an explicit 'Use when...' clause naming the situations to invoke the skill (e.g. 'Use when executing an NFT trade — buying a listing, accepting an offer, or sweeping listings') to raise completeness.

Include a few more natural trigger synonyms users might say (e.g. 'purchase NFTs', 'fill an order', 'accept a bid') to broaden trigger-term coverage.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — "Fulfill listings, accept offers, create new orders, cross-chain purchases, and sweep multiple listings" — with comprehensive coverage of the skill's trade-execution capabilities.	5 / 5
Completeness	It clearly states what the skill does (the enumerated actions) and provides a scope-out trigger ("for read-only queries use opensea-api instead"), but lacks an explicit forward "Use when..." trigger phrase naming the situations to invoke it.	4 / 5
Trigger Term Quality	Natural terms like "Buy and sell NFTs", "fulfill listings", "accept offers", and "cross-chain purchases" are present and recognizable, though common synonyms or specific file/extension-style triggers are not exhaustively covered.	4 / 5
Distinctiveness Conflict Risk	The trade-execution niche is distinct and the explicit handoff ("for read-only queries use opensea-api instead") sharply separates it from sibling skills, minimizing conflict risk.	5 / 5
	Total	18 / 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: 1e2e2e2

Reviewed: 6 days ago

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