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

Annotations already mark this as non-readonly and non-idempotent; description adds crucial behavioral details: the key is shown only once and can't be retrieved later, and there is a quota of five active keys. These are not inferable from schema or annotation.

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 with the primary action first, followed by two high-value constraints. No filler or repetition.

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 one-optional-parameter create tool with no output schema, the description covers purpose, quota, and the one-time visibility of the key. It doesn't spell out that the label is optional or what happens when the five-key cap is reached, but these are minor given the low complexity.

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 0% and the description never explains the 'label' parameter or how it relates to the 'machine or assistant' framing. The param name and maxLength in schema are the only signals, so the description adds no semantic value for the one parameter.

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?

Description identifies the operation with the verb 'Mint' and the resource 'API key', and qualifies it as an additional key for another machine or assistant. This clearly differentiates it from siblings like list_api_keys and revoke_api_key.

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?

States the intended context: create an extra key for another machine or assistant, and warns that five active keys is the maximum. It does not explicitly name when not to use list/revoke siblings, but the context is clear enough.

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