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

With no annotations provided, the description carries full burden. It discloses that results are 'ranked' and may include an 'optional answer', but it doesn't mention pagination, rate limits, payment failures, or behavior differences from standard Tavily. The x402 note provides some context on payment but is terse.

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 compact and front-loaded with the key info (endpoint, payment, result shape). The cost mention ($0.01) is useful. However, it's slightly fragmented with the 'Same shape as Tavily x402' tail, but overall minimal and informative.

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 has 13 parameters and no output schema, the description is insufficient to fully guide invocation. It fails to document most parameters or the response structure beyond basic snippets. For a tool this complex, more detail on parameter semantics and expected output is needed. It's decent for a simple read, but incomplete for parameter handling.

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 only 8% (only 'query' has a description). The description mentions only '{ query }' and 'optional answer', leaving topic, time_range, include_answer, etc. entirely undocumented. The description does not compensate for the low schema coverage, so agents must guess semantics for 12 of 13 parameters.

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 performs a Tavily-compatible POST /search returning ranked web results, snippets, source URLs, and optional answers. It uses a specific verb ('search') and resource ('Tavily-compatible POST /search'), and it distinguishes from web_search/web_scrape siblings by specifying the Tavily-compatible interface and x402 payment.

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 mentions the endpoint and body format but doesn't give explicit when-to-use guidance or contrast with alternatives like web_search. The x402 payment note implies a paid usage context, but no exclusions or alternatives are named beyond the implicit 'Tavily-compatible' branding.

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