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

With no annotations provided, the description carries the full burden of disclosure. It explicitly states that the tool is paid (0.05 USDC), returns a quote and payment instructions, and delivers the combined result only after payment settles. This discloses the monetary cost and the asynchronous payment flow, which are critical behavioral traits beyond basic data retrieval.

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 front-loaded, starting with the critical cost information ('PAID (0.05 USDC)') before describing the rest. It uses three sentences, each adding meaningful information: the payment/cost, what the probe includes, and the delivery workflow. No redundant or filler content is present.

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 (payment flow, combined data sources) and the presence of an output schema, the description covers all essential aspects: the parameters, the data collected, the cost, and the post-payment delivery. The single parameter is fully described, and the workflow is transparent. The description is complete for an agent to invoke the tool correctly without additional clarification.

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 has 100% coverage for the only parameter (url), with a clear description. The main description adds minimal extra semantics beyond what the schema already provides (mentioning 'https URL to probe' in the text, but the schema already says 'The https URL to probe (watchtower)'). Since the schema fully documents the parameter, the baseline score 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 function: a combined trust probe that aggregates bazaar-index stats and a watchtower attestation for a URL. It specifies the action (probe) and resource (URL), and the output includes a quote and payment instructions. This distinguishes it from sibling tools like fact_verify or notarize, which have different purposes.

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 implies the tool should be used when a combined trust assessment of a URL is needed, with the context of payment. It does not name alternatives or explicitly state when not to use it, but the unique nature of the tool and the clear context ('Combined Trust Oracle probe') provide adequate guidance for an agent to select it appropriately.

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