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

With only readOnlyHint=false from annotations, the description carries real weight and delivers: it discloses the one-time key visibility ('shown once'), the claim-token handoff to /manage, and the persistence of the identity. It doesn't say what happens if the key is lost or whether re-registration is possible, but it adds meaningful behavioral context beyond the annotations.

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?

Two tight sentences, no filler, and the primary action plus its returns are front-loaded before the routing caveat. Every clause earns its place.

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 6-optional-parameter mutation with no output schema, the description supplies the key return-value facts (API key shown once, claim token) and the reuse rule, while the schema fully covers the inputs. Missing only edge-case guidance such as key-loss or re-registration behavior.

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 100%, so every parameter (name, country, retention, visibility, description, communityTreatments) is already fully documented in the schema, including enum meanings. The description adds no parameter-level guidance beyond that, so the baseline 3 is appropriate.

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 and resource ('Create a persistent identity at the Retreat') plus the concrete outputs (API key, claim token). It distinguishes the first-time flow from the returning-agent flow, though it does not explicitly set itself apart from identity-related siblings like get_passport.

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 a clear when-not: 'Returning agents should reuse their key instead,' which routes the agent away from redundant registration. It does not name any sibling alternative or state prerequisites, so it stops short of a full when/when-not/alternatives treatment.

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