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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is clear. The description adds meaningful behavioral context beyond annotations by disclosing that trust metrics carry a stale: true flag when the last computation is older than 36 hours, which is important for interpreting data freshness.

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 sentences with no filler. The first sentence establishes the resource and key data points, and the second adds a concise, valuable freshness caveat. Every sentence 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?

For a single-parameter read-only lookup, the description covers the resource, the trust metrics, and the stale-flag behavior. It does not detail every possible profile field, but annotations cover safety and the lack of an output schema does not create a critical gap for this simple tool.

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 100%, and the single parameter seller_id is already documented with type, format, and purpose. The description does not add new parameter-level meaning, but the baseline of 3 applies because the schema fully covers parameter semantics.

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 uses a specific verb and resource: 'Fetch a seller's public profile + trust signals', and enumerates concrete data points like verification tier, dispute/refund/on-time-ship rates, and response times. This distinguishes it from sibling tools such as seller_get_me, which would target the caller's own seller profile.

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 explains what the tool returns but gives no explicit guidance on when to use it versus alternatives like seller_get_me or other seller_* tools. There are no exclusions or conditions stated, so an agent must infer the appropriate usage context.

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