list_timezones

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds some context by mentioning the use of the system's full IANA timezone database, but does not detail aspects like rate limits, authentication needs, or the format of the returned data (e.g., list structure, pagination). It adequately describes the operation as a read-only list without contradictions.

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 front-loaded with the core purpose in the first sentence and efficiently adds filtering details in the second. Every sentence earns its place by providing essential information without redundancy, making it appropriately sized and well-structured.

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?

Given the tool's low complexity (2 parameters, no annotations, no output schema), the description is mostly complete. It covers the purpose, source, and filtering options. However, without an output schema, it could benefit from mentioning the return format (e.g., list of timezone objects with offset and time) to fully compensate for the lack of structured output details.

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 schema already fully documents the two parameters (query and continent). The description adds marginal value by mentioning filtering by query text or continent, but does not provide additional semantics beyond what the schema descriptions specify (e.g., examples of continent prefixes). Baseline 3 is appropriate as the schema handles most of the parameter documentation.

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's purpose with a specific verb ('List') and resource ('IANA timezones'), and distinguishes it from siblings by specifying it provides timezone data with current offset and time, unlike other tools that perform calculations or conversions. It explicitly mentions the IANA database source.

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 provides clear context for usage by stating it can filter by query text or continent, which helps differentiate it from other time-related tools. However, it does not explicitly mention when not to use it or name specific alternatives among the siblings, such as 'convert_timezone' or 'get_current_time', for comparison.

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