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

Annotations already cover the safety profile (not read-only, idempotent, non-destructive, closed-world), and the description adds genuinely non-obvious behavior: keys younger than 7 days require NIP-13 proof of work of 16, kind 4202 payments are verified on chain against the service payTo, and the response returns the log inclusion. It does not say what happens on rejected or duplicate submissions, 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?

The purpose is front-loaded in the first clause and every clause carries payload requirements rather than filler. It is dense and run-on, with per-kind tag lists packed into nested parentheticals that are harder to scan than a bulleted layout, but nothing is redundant.

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 an output schema exists, the description need not explain return values, though it helpfully notes the log inclusion is returned. It covers all supported kinds, tag semantics, and the proof-of-work edge case; only error/rejection behavior and guidance on unsupported kinds remain unspecified.

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% and the single parameter is a nested object, so the schema does the structural work. The description still adds real meaning the schema cannot express: which tag keys (d, x, r, p, e, status, tx, outcome) each kind requires, that kind 4200 content must be empty, and the allowed network/outcome value sets.

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 states a specific action ('submit one Nostr event signed by YOUR key') and then enumerates the exact event kinds accepted (30422 release, 0 passport, 4200 receipt, 4201 confirmation, 4202 purchase report). An agent knows precisely which payload shapes this tool accepts, which distinguishes it from invoice or discovery siblings.

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?

Each kind carries its own triggering condition, e.g. kind 4202 is for use 'after paying an x402 endpoint', and the signer is told to 'sign locally; never send keys'. What is missing is explicit routing away from siblings such as report_purchase or create_invoice, and any statement of which kinds are not accepted here.

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