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

With no annotations, the description carries the full burden and does disclose the critical behavioral trait: the old key stops working immediately. This is a key side effect. However, it does not explicitly state that the new key is returned in the response, though it is implied by 'update your site with the new key.' Lacks mention of permissions or reversibility.

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 sentences, front-loaded with the purpose, followed by the key consequence and required action. Every word earns its place; no fluff or redundancy.

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 zero-parameter, security-sensitive action, the description covers purpose, immediate invalidation, and follow-up step. It could be more explicit about the response containing the new key, but the instruction to update the site with the new key implies it. No output schema exists, so the description partially compensates.

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?

The input schema is empty with 0 parameters, so the baseline is 4. The description adds no parameter-specific meaning but does not need to; the tool takes no parameters.

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 clearly states the action ('Rotate the public site API key') with a specific verb and resource, and distinguishes it from siblings like get_site_api_key by focusing on rotation rather than retrieval. The sentence immediately clarifies what rotation entails.

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 implies when to use the tool by explaining the consequence ('The old key stops working immediately') and instructing to update the site with the new key. It indirectly warns against rotating unless ready to update, but does not explicitly name alternatives or exclusions.

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