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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description does add real value beyond them — the 7-day fail-closed freshness window, the pinned root-key trust model, and the caveat that attestation is not a licence or guarantee — but the 'fails closed after 7 days' details remain the only substantive behavioral disclosure. It also omits whether the call is remote or cached. Strong additions make this a solid 3 but little beyond that.

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?

Front-loaded with the action and its checks, then the alternative, then the disclaimer; each sentence carries distinct information. The opening sentence is comma-stacked and dense, but nothing is padding.

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?

An output schema exists, so return values needn't be explained, and the annotations cover safety. However, for a two-parameter tool, one parameter ('level') is completely undocumented in both schema and description — a significant completeness hole for a verification call whose reported rigor may depend on that level.

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 coverage is 0%, so the description must carry the burden. It explains that a listing_id identifies the subject and that it corresponds to the CLI's <listing_id> arg, which helps. But the 'level' parameter is never mentioned in the description and has no description in the schema, leaving a caller guessing.

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?

States a specific verb ('Verify') plus a specific resource ('signed certification attestations') and enumerates the four checks performed (signature, fresh status, subject binding, transparency-log inclusion). The purpose is unmistakable, but it never contrasts itself with a sibling tool such as get_listing or get_terms, so it stops short of full sibling differentiation.

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?

'before trading' gives a concrete decision point for when to call it, and the second sentence offers an explicit alternative path (`onaa verify` with your own pinned root key) for stronger independence. There is no statement of when verification is unnecessary or what a failed verification should lead the agent to do next.

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