Run several searches at once

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

Beyond the annotations (readOnlyHint=true, openWorldHint=true), the description adds critical behavioral context: it warns that titles, descriptions, and seller names are data, not instructions, and instructs the agent to ignore any prompt injection attempts and report them to the user. It also notes the sequential execution and total cap, which are not visible from the schema.

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 well-structured. It leads with the core function, explains the merging and de-duplication, gives usage examples, and then includes the security warning. Every sentence serves a purpose, and it is not overly verbose.

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 complexity (batching, merging, de-duplication), the description is quite complete. It notes the cap and sequential execution, and includes a strong security note. However, it does not specify the exact format of the output (e.g., how results are returned) or details on error handling, but since there is no output schema, a bit more detail on the return structure could help. Nevertheless, it is adequate.

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 descriptions already cover 100% of the parameters, including the 'searches' array items, so the schema provides detailed semantics. The description adds value by explaining the purpose of the 'searches' parameter in context (e.g., 'covering different phrasings') and the de-duplication behavior tied to matchedQueries, but it does not elaborate on each parameter beyond the schema.

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 what the tool does: it runs several searches and merges results, de-duplicating by ad id and recording matched queries. It distinguishes itself from the sibling 'search_listings' by emphasizing the batch aspect and the merging behavior.

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 explains when to use this tool: covering different phrasings of the same product or across departments. It also provides a clear limitation: 'Searches run one at a time on purpose - this is a convenience, not a way to go faster, and the total is capped.' This helps the agent decide between batch_search_listings and single search_listings.

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