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

Annotations already declare non-readOnly, non-destructive, non-idempotent, so safety is covered. The description adds genuinely useful behaviour the annotations cannot carry: the secret is returned once and never stored, and writes on activities/settings/tommos scopes require an admin or owner. It stops short of describing what the response contains or whether the key can be re-fetched later.

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 the purpose before the caveats. The phrasing ('answered once and kept nowhere') is slightly informal but carries meaning economically; nothing is redundant with the schema.

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 mutation tool with no output schema, the description covers the essential behaviour an agent needs: the one-time secret delivery and the permission gate on certain scopes. Missing only return-shape and expiry interaction detail, which is minor given the schema documents expires_in_days.

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 baseline is 3, but the description adds meaning beyond it: it flags a subset of write scopes (activities:write, settings:write, tommos:write) as admin-granted, information present nowhere in the enum or the individual property descriptions. This materially helps scope selection.

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 ('Make an API key') and narrows scope to the agent-with-no-person case, which cleanly separates it from list_api_keys and revoke_an_api_key in the sibling set. An agent can identify the operation without opening the schema.

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 condition for use ('for an agent with no person behind it, with only the scopes it needs') and a prerequisite for privileged write scopes (admin or owner). It does not explicitly name list_api_keys/revoke_an_api_key as the alternatives, so it stops short of full routing guidance.

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