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

Annotations establish this is a non-idempotent write that is not destructive, and the description adds the critical consequence the annotations cannot express: losing the token means losing the library unless claimed. It also points to the claim endpoint that preserves the data, which is genuinely valuable behavioral 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?

Three short sentences, front-loaded with what is created and what it costs to lose it. The final sentence ('Then the account keeps what the token saved') partially restates the preceding claim condition and is the weakest line.

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?

With no parameters, no output schema, and annotations already covering the safety profile, the description supplies the remaining need: the persistence/ownership model around the token. It does not describe the returned token payload, but with no output schema that omission is minor.

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?

There are zero parameters, so the baseline is 4. The description reinforces this by stating no e-mail or other input is required, which is the only parameter-relevant fact available.

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 (creates a guest) plus the concrete token prefix `ipt_…`, which lets an agent recognize the artifact it produces. No sibling tool in the list creates guests or tokens, so it is unambiguously distinguishable.

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?

Implies usage context ('asks for no e-mail and no other data' suggests anonymous onboarding) and names the follow-up path `POST /api/auth/claim`, but never states explicitly when to choose this over an account-based flow or what preconditions exist. Usage is inferred rather than instructed.

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