Create API Key

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

With no annotations, the description takes on the full burden of behavioral disclosure and does so well by warning that the token is only shown once and MUST be displayed to the user. This is a critical, non-obvious behavior that an agent needs to handle correctly.

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 concise sentences front-load the core action and immediately follow with the critical security behavior. Every word earns its place, and the must-display note is actionable.

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 simple create operation with three optional/required parameters and a detailed schema, the description is largely complete: it says what is created, and the token-display warning addresses the only truly hidden part of the response. It could mention response shape beyond the token, but this is only a minor gap.

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 the parameter details live entirely in the schema. The description adds no additional parameter-level meaning, but per the baseline for high schema coverage, this is adequate.

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?

The description uses a specific verb ('Create') with a clear resource ('a new API key in Resend') and immediately distinguishes this from sibling tools like list-api-keys or remove-api-key. The one-time-token warning further clarifies what makes this operation unique.

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?

The description does not state when to use this tool versus alternatives like update-api-key or list-api-keys. While 'Create' strongly implies its own use case, there is no explicit guidance on prerequisites, decisions between full_access and sending_access, or exclusions.

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