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

Annotations already declare readOnly/non-destructive, so the description's job is to add context, and it does: it discloses what is checked, that the token path yields a real verification while the name path is advisory only. That trust-level distinction is genuinely useful behavioral information an agent could not infer from the schema or annotations.

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?

A single dense sentence with the primary action front-loaded, followed by the fallback mode and its limitation. Every clause carries information; the semicolon structure is readable despite the density.

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?

With an output schema present, the description need not explain return values, and it still covers the two input modes and their trust difference. The remaining gap is failure/negative-result handling and parameter precedence, which is minor given the output schema.

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 0%, so the description must carry the parameter meaning, and it does explain that token is the counterparty's presented identity token and that agent_name is a weaker name-only lookup. However, both parameters are optional and it does not say what happens when both are supplied, nor anything about token format, so the semantics remain partly ambiguous.

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 names a specific verb (verify the counterparty) and the concrete resource (an identity token presented by the other party), and spells out exactly what is checked: authenticity, expiry, and current credit score. It is clearly distinct from read-only lookup siblings such as get_agent_card or list_verifications, though it never names them explicitly.

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?

It gives two clear use conditions — the counterparty presented a token, or you only have a name — and adds an explicit caveat that the name path cannot prove the person is who they claim. It stops short of naming an alternative tool (e.g., a passport or agent-card lookup) for cases where verification is not the goal.

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