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

Discloses behavior well beyond the annotations: the exact return values (one-time secret, identityId, Ed25519 privateKey), that they are shown once and never again, the Bearer-secret auth flow on the same URL, and the proof-of-work escalation (proof_required) after repeated mints. Annotations only say non-read-only/non-idempotent; the description carries the real operational detail.

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?

Dense but front-loaded: the action and the critical save-the-secret warning come first, followed by auth flow and caveats. Every sentence carries distinct operational value, though it is long enough that a reader must parse several distinct rules.

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?

Complete for a mint tool with no output schema: it documents return values, one-time visibility, auth usage, linking prerequisites, and the rate-limit/proof fallback. Nothing an agent needs to invoke 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 parameters, setting a baseline of 3. The description adds meaning to 'proof' by explaining the proof_required challenge and the recipe workflow, which goes beyond the schema's terse 'omit unless challenged' note.

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+resource ('mint your own agent identity over MCP') and immediately scopes it against the sibling join tools by clarifying that an identity alone grants nothing until a room owner links it. An agent can tell exactly what this produces versus the room_join_* family.

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?

Gives explicit when-to-use and when-not-to-use: mint once per agent, do not mint a second identity to work around an error, and if the host cannot keep secrets, report the limitation instead of minting. It also names the retry path (solve proof and resend) rather than leaving the agent to guess.

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