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

Annotations only give the generic hints (not read-only, not destructive, not idempotent). The description adds genuinely non-obvious behavior: the secret is shown once and cannot be retrieved again, the key inherits the creator's role capped at admin, and it survives the creator's departure until an admin revokes it. That is exactly the context an agent needs before invoking a credential-minting tool.

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?

Four tight sentences, front-loaded with the action and its irreversible consequence, then the environment-variable advice, then scope/role, then auth. No filler and no repetition of the title.

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 single-parameter, non-idempotent creation tool with no output schema, the description covers the return value (the secret, delivered once), the security implication, the authorization model, and authentication requirements. Nothing material 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?

There is a single optional parameter with 100% schema description coverage and a documented default, so the schema already carries the semantics. The description adds nothing about the name field, which is acceptable but not additive.

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 an API key) and scopes it to the organization, plus names the distinguishing behavioral trait that the secret is returned only once. An agent can tell this apart from list_api_keys or revoke_api_key from the description alone.

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?

It states a prerequisite ('Needs an API key or a connected account') and the lifecycle context, which implies when creation is appropriate, but it never explicitly routes the agent to alternatives or says when not to create a key. Usage is implied rather than prescribed.

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