tz_offset

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

No annotations are provided, so the description carries the full burden. It mentions DST-awareness and fractional offset handling, but it does not disclose potential behavioral traits such as error handling for invalid timezones, rate limits, authentication needs, or the format of the returned offset. The description is minimal and lacks depth beyond the core function.

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 two concise sentences that front-load the core purpose and include a helpful example of fractional offsets. Every word adds value, with no redundant or tangential information.

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 tool with 2 parameters and no output schema, the description covers the essential purpose and DST-awareness. However, it does not specify the return format (e.g., string like '+05:30'), error scenarios, or edge cases. While minimal, it is adequate for a straightforward tool.

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%, providing descriptions for both parameters (instant and timezone). The description adds that instant defaults to 'now' and references IANA timezones, but it does not add significant new meaning beyond the schema. The baseline of 3 is appropriate.

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 returns the exact UTC offset of a timezone at a given instant, with DST awareness, and specifically highlights handling of fractional offsets like India +05:30 and Nepal +05:45. This differentiates it from sibling tools like convert_timezone (which converts time) or list_timezones (which lists names).

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 the tool should be used to get the UTC offset at a specific instant, but it does not provide explicit guidance on when to use it versus similar sibling tools (e.g., lookup_timezone) or when not to use it. No alternatives are mentioned, so the usage context is only implicitly clear.

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