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

The description adds valuable non-obvious context beyond annotations: it discloses that the tool is 'Unofficial, independent Actor; not affiliated with or endorsed by any named source publisher' and provides pricing ('$0.02/call, x402 (USDC on base)'). These details supplement the openWorldHint and readOnlyHint flags with cost and affiliation information. It does not contradict annotations, and no major behavioral gaps remain glaring.

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 two concise sentences: the first states the core function, and the second adds necessary caveat and pricing info. Every clause earns its place, and the structure is front-loaded with the purpose. No redundant or verbose language.

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?

The tool has 7 parameters and no output schema. While the input schema is rich, the description does not explain what the tool returns (e.g., benchmark results, comparative metrics, or reports). The name 'benchmark' hints at the output, but the agent is left without clear expectations about the response structure, especially given the tool's cost and independence caveat. A statement about return format would complete the context.

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?

With schema description coverage at 100%, all parameters already have detailed descriptions in the input schema. The main description adds no parameter-specific meaning beyond what the schema provides. The schema itself explains idempotency, limits, and field semantics thoroughly, so 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: 'Compare customer-owned property facts with licensed public Sahibindex market reports.' It specifies the verb (compare), the resource (property facts vs. market reports), and the scope is evident from the name and sibling context (benchmark for property markets). This distinguishes it from the unrelated sibling tools.

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 usage (comparing property facts against market reports) but does not explicitly state when to use it vs. alternatives. The input schema adds a negative constraint ('Listing URLs and listing-page scraping are not supported') but no positive use cases or alternative tool exclusions. Since the purpose itself provides enough context to infer when to invoke, it earns a 3; however, it lacks explicit guidance.

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