search

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds meaningful context beyond annotations: Facebook results use the server's default location due to the contract carrying no location, and results expose ids compatible with the fetch tool.

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 front-loaded with the core purpose and is compact overall. Each clause adds useful routing or behavioral context, though the explicit 'Behavior: read-only' phrase is redundant with the readOnlyHint annotation.

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 there is no output schema, the description helpfully explains that results contain ids in marketplace:listingId form usable with the fetch tool. It also covers the main location caveat and exclusions, making it reasonably complete for a single-parameter search tool.

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?

Schema description coverage is 100% and the only parameter, query, is described as a search query string. The description adds little beyond restating that a single query string is used, so the baseline of 3 is appropriate.

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's verb and resource: search every available secondhand marketplace with a single query string. It also distinguishes itself from siblings by noting that search_marketplace is preferred when a location matters and that this tool is not for filtered or local searches.

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 explicitly provides when-to-use and when-not-to-use guidance: it says to prefer search_marketplace when a place matters and states that this tool is not for filtered or local searches. It also explains the downstream use case of passing returned ids to the fetch tool.

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