Convert a wall-clock datetime (YYYY-MM-DDTHH:MM(:SS)?) from one IANA timezone to another using the platform Intl database. Pure/offline; price 0.0 (free).
| Name | Required | Description | Default |
|---|---|---|---|
| toTz | Yes | Target IANA timezone (e.g. Asia/Tokyo) | |
| fromTz | Yes | Source IANA timezone (e.g. America/New_York) | |
| datetime | Yes | Wall-clock datetime, YYYY-MM-DDTHH:MM(:SS)? |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the responsibility. It discloses meaningful traits: uses the platform Intl database, is pure/offline, and costs nothing. However, it does not mention output format, handling of invalid timezones, or DST behavior, leaving some behavioral ambiguity.
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 a single sentence that front-loads the action and format specification. It includes all essential details (what, format, method, purity/cost) with zero filler.
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 conversion tool, the description covers input format, method, and constraints. It does not explicitly describe the return value, but that is implicit for a converter. The lack of an output schema creates a minor gap, but overall completeness is adequate.
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 coverage is 100% with each parameter described in the input schema. The description restates the datetime format but adds no new parameter-specific details beyond what the schema already provides, so it does not elevate the baseline.
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 'Convert a wall-clock datetime from one IANA timezone to another using the platform Intl database', giving a specific verb and resource. It is unambiguous and distinguishes itself from sibling holiday_calendar_* tools which focus on holidays, not 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 implies usage for timezone conversion but does not explicitly state when to use it over alternatives or provide exclusion criteria. The 'Pure/offline; price 0.0' note hints at a safe, free choice, but no direct comparison with other tools is offered. Usage context is inferable from the name and description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.