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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description earns credit for a genuinely non-obvious behavior: verification is against the agent's *live* level and status, and validity is revoked when the level drops, the key rotates, or the registration lapses — a stale cached pass is not sufficient. It omits any auth requirements or failure/error semantics, so not a 5.

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 front-loaded sentence that leads with what is verified and follows with the invalidation semantics; no filler. The parenthetical is dense but every clause carries information, though the run-on structure makes it slightly harder to scan.

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 3-optional-param verification tool with an output schema, the description need not explain return values, and it covers the essential behavioral nuance (live-state dependence). The remaining gap is input selection — which of token/signature/credential to supply — which is not addressed anywhere given 0% schema coverage.

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% across three undocumented parameters, so the description must compensate. It partially does: naming 'a kya+jwt token' versus 'a signed ...Credential' loosely maps to the token/signature pair versus the credential object, but it never states which parameters go together or whether any are mutually exclusive — and all three are optional.

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) and the two concrete resources it accepts (a kya+jwt token or a signed RightsholdKYACredential), plus what is checked: issuer signature, expiry, live level and status. An agent knows exactly what the tool does. It does not explicitly differentiate itself from the near-siblings kya_check, kya_lookup, or ledger_verify, which keeps it at 4.

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?

Usage is implied by the purpose (use to validate a credential before relying on it), and the invalidation clause hints at why you would re-verify rather than cache a pass. However, no when-to-use or when-not-to-use guidance is given relative to kya_check/kya_lookup/check_license, and there are no stated prerequisites.

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