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

No annotations are provided, so the description carries the behavioral disclosure burden. It does disclose the pay-per-use cost ('0.1 USDC on Base') and that it uses web sources, which is useful. However, it does not mention the output shape, failure modes, or whether this is a read-only operation, leaving meaningful behavioral gaps.

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 extremely concise, front-loaded with the purpose, and includes the necessary input hint and cost information without any redundancy. Every element earns its place.

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 low complexity—one input parameter and no nested schema—the description provides enough context: purpose, input type, source type, and cost. It does not describe the response format, but for a simple fact-check tool the expected output is reasonably inferable. The absence of an output schema slightly lowers completeness but is not critical here.

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 input schema describes the single parameter only as 'service input,' which is generic. The description adds meaningful semantics by stating 'input=claim', clarifying that the string should be a factual claim to verify. With schema coverage at 100%, this added clarification raises the score above baseline.

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 identifies the operation as a 'quick fact-check with web sources' and specifies the input as a claim. The 'quick' qualifier suggests a lighter-weight alternative to the sibling 'fact-check' tool, though it does not explicitly name the distinction. Overall the purpose is clear and operational.

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 'CONSUMER:' prefix and 'quick' descriptor indicate this is meant for lightweight, general-audience fact-checking, and the pay-per-use cost clarifies the commercial context. It does not explicitly say when not to use it or name an alternative, but the implied usage context is clear enough for an agent to select it for quick verification tasks.

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