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

With no annotations, the description carries the full burden and delivers: deterministic one-shot retrieval, drains ONLY the pinned rendezvous relay, deletes and NACKs mismatched DMs without revealing the expected phrase, returns a new Operator-signed proof grant envelope bound to patron/challenge/duration that must be replayed on every subsequent paid call, and is free. That is unusually rich operational, destructive, and auth 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?

Front-loaded purpose sentence, then clearly segmented flow context, call-timing constraint, mechanics, and return contract. It is on the longer side but nearly every sentence earns its place; minor slack in the parenthetical and envelope formatting.

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 flow-completing retrieval tool with an output schema, the description supplies the timing preconditions, the redeemable result contract (the grant envelope and its replay obligation), and the destructive side effect on mismatched DMs. Nothing an agent needs to call it correctly is missing.

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 the schema already documents both params and the baseline is 3. The description adds meaning beyond the schema by clarifying that dpop_token is the value returned by request_npub_proof and that the retrieval key is (patron_npub, dpop_token), tying the params to the flow step.

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 (receive) and resource (npub ownership confirmation), and positions itself precisely in the flow: it is the completion of the npub-OWNERSHIP-PROOF flow and the counterpart of receive_credentials. An agent can distinguish it from receive_credentials, request_npub_proof, and check_proof_status without opening other schemas.

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?

Explicit when-to-call ('Call this only after the user confirms they have replied'), explicit when-not-to-call ('If called before the user replies, their message will never be found'), and explicit anti-patterns ('Do NOT poll, loop, or retry'). It also names the predecessor tool (request_npub_proof) whose output feeds this one.

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