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

Annotations already indicate readOnly, idempotent, non-destructive. Description adds that it matches sponsor names and domains, returns citable documents, and that results' IDs can be passed to fetch. No contradictions.

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?

Two sentences with purpose and usage guidance front-loaded. The first sentence is somewhat verbose with 'deep-research/Responses-API compatibility interface' but overall concise.

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 a simple tool with one parameter, strong annotations, and an output schema, the description is complete. It explains the output format (citable documents, IDs) and how to use with fetch.

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?

Only one parameter (query) with schema description coverage at 100%. The description's mention of 'sponsor name, product, or domain' matches the schema's description exactly, adding no extra meaning. Baseline 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 it searches a database for brands that sponsor podcasts, and distinguishes itself from sibling tools like search_sponsors and fetch by specifying its role as a simple search that returns IDs for fetching full profiles.

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?

Explicitly tells when not to use this tool and which alternative to use for filtered/paginated search: 'For filtered or paginated search (category, industry, recency), use search_sponsors instead.' Also pairs with fetch.

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