Date-time Tools MCP

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 effectively describes the tool's behavior by specifying required input formats (luxon format, IANA timezones) and the prerequisite tool invocation for certain scenarios. However, it doesn't mention error handling, rate limits, or authentication needs, which would be helpful for a complete behavioral picture.

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 appropriately sized and front-loaded with the core purpose in the first sentence. The bullet points efficiently convey important constraints and prerequisites. While every sentence earns its place, the formatting as bullet points (though clear) could be slightly more streamlined for pure text consumption.

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 moderate complexity (timezone conversion with format constraints), no annotations, and no output schema, the description does well by covering purpose, usage guidelines, and behavioral constraints. However, it doesn't describe the return format or error responses, which would be helpful for completeness since there's no output schema.

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 documents all three parameters thoroughly. The description reinforces the format requirements (luxon format, IANA timezones) but doesn't add significant semantic meaning beyond what's in the schema. This meets the baseline expectation when schema coverage is high.

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 specific verb ('converts') and resources ('date time string from one timezone to another'), and it distinguishes from sibling tools by not overlapping with 'currentDateTimeAndTimezone' (which provides current info) or 'mutateDate' (which suggests date manipulation rather than timezone conversion).

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 explicit guidance on when to use this tool vs alternatives: it specifies that for relative dates/times or unspecified dates, the agent must first invoke 'currentDateTimeAndTimezone' to get the user's current context. This creates clear prerequisites and distinguishes usage scenarios from the sibling tools.

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