browse_shelf

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses important behavioral traits: the tool costs $0.003 via x402, requires WALLET_PRIVATE_KEY and USDC on Base, and returns a ranked list of books. It also mentions the shelf catalog URL for discoverability. The description does not explicitly state it is read-only, but the purpose and output format imply a safe browse operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise and front-loaded with the tool's primary purpose. The subsequent sentences add essential operational details (return format, catalog URL, cost and requirements) without unnecessary fluff. The longer category list is justified as it directly informs valid parameter values.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (one parameter, no output schema), the description is complete: it explains what the tool returns, how to discover available shelves, and the cost/auth requirements. It also implicitly ties into sibling tools by mentioning 'book_id for drill-down', which supports the overall workflow.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema covers 100% of the parameter with a description, but the tool description adds significant value by enumerating example shelves (e.g., 'gothic-fiction', 'russian-literature') and clarifying that there are 100+ auto-generated shelves beyond the 10 hand-picked ones. This goes beyond the schema's basic example of 'gothic horror' or 'russian-literature' and enriches the agent's understanding of valid inputs.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool browses a curated category/subject shelf and returns a ranked list of books with book_id for drill-down. It distinguishes itself from sibling search tools by explicitly mentioning curated shelves and listing specific categories, making the scope and resource clear.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for when to use this tool: to browse curated shelves rather than perform a general search. It also hints at the next step (drill-down with book_id) and mentions the shelf catalog is discoverable at a URL. However, it does not explicitly state exclusions or directly compare with alternatives like search_books, so it falls slightly short of a perfect score.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.