Fetch Timezones

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

The description discloses the HTTP method (GET), the auth token location ('Token: location'), and the required scope ('locations.readonly'), going beyond the annotations. It is consistent with the readOnlyHint and idempotentHint, and does not hide the read-only nature. It does not describe return formatting or potential empty-result behavior, but the annotations already cover the safety profile.

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?

The description is short and mostly efficient, but it opens with an unnecessary duplicate of the title: 'Fetch Timezones Fetch the available timezones.' That repetition wastes two words and makes the structure feel accidental rather than deliberately front-loaded. The endpoint and auth details are compact and useful.

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 read-only list tool, the description covers what it returns, the endpoint, and auth requirements. However, it references a path parameter, locationId, that is not present in the input schema, so an agent could be uncertain whether it must somehow supply that value or whether it comes from the token context. There is no output schema, and the return shape is only implied as a list of timezones.

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 are zero declared parameters, so the baseline is 4. The endpoint path '/locations/{locationId}/timezones' does imply a location-scoped resource, adding context about what the result depends on. The description does not explain how locationId is supplied, but with no parameters in the schema this is not an immediate description failure.

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 tool fetches available timezones, and the included endpoint specifies the resource path. It is distinguishable from all sibling tools, none of which target timezones. However, the opening repeats the title verbatim ('Fetch Timezones Fetch...'), which is redundant and slightly muddies the clarity.

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 intended usage is implicit: call this tool when you need the list of timezones available for a location. There are no competing timezone tools among the siblings, so no alternative routing is necessary. It does not explicitly state when not to use it or provide prerequisites beyond the described token/scope.

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