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

With no annotations provided, the description carries the full behavioral burden excellently. It discloses that the operation is free, has no side effects, touches no relay, reads expiry from the grant itself, and consults only the patron's revocation watermark — all critical read-only safety and data-source context.

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 front-loaded with the core purpose and then adds only sentences that earn their place: the flow analogy and caller motivation, the expiry/revocation detail, and the no-side-effects guarantee. There is no redundant restatement of name or schema.

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?

Given the simple two-parameter read-only check, the presence of a full input schema and an output schema, and the absence of annotations, the description provides everything an agent needs: what it checks, when to call it, what it consults, and its safety profile. Return values need not be explained because an output schema exists.

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 100%, so baseline is 3. The description adds meaningful context beyond the schema by framing dpop_token as the token that the next paid call must accept and by explaining that patron_npub drives consultation of the patron's revocation watermark, giving both parameters purpose beyond their raw definitions.

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 first sentence states a specific verb and resource: check whether a proof grant is still valid. It further distinguishes the tool within the proof flow by tying it to the paid-call acceptance question and by contrasting it with check_oauth_status for the OAuth flow.

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 gives a clear pre-flight context: use this before burning credits on a guaranteed failure, and it names an analogous alternative (check_oauth_status) for a different flow. It does not spell out explicit when-not conditions or name the sibling tools it should be preferred over, so it falls short of a full 5.

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