time_by_coordinatesResolve the timezone for a latitude/longitude coordinate (via geo-tz) and return the local time there.
| Name | Required | Description | Default |
|---|---|---|---|
| at | No | Optional ISO 8601 instant to evaluate instead of now (read as UTC if it has no zone). | |
| latitude | Yes | Latitude in degrees [-90, 90]. | |
| longitude | Yes | Longitude in degrees [-180, 180]. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate read-only and idempotent behavior. The description adds that it uses geo-tz and returns local time, but lacks details on edge cases (e.g., ocean coordinates) or whether it returns timezone name alongside time.
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?
Single sentence, 18 words, front-loaded with main action. Every word serves a purpose; no redundancy.
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?
Without an output schema, the description should clarify the return format. It only says 'return the local time,' which is vague. The essentials are present but incomplete for full agent guidance.
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 covers 100% of parameters with descriptions. The description does not add any new information beyond the schema, so baseline score 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?
Clearly states it resolves timezone and returns local time for coordinates. However, it does not explicitly differentiate from siblings like search_cities or get_current_time, but the coordinate-based approach is distinct.
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?
No guidance on when to use this tool vs alternatives. The description does not mention prerequisites or situations where it is preferred over get_current_time or convert_time.
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.
Tools are mostly distinct, but convert_time and get_current_time have overlapping functionality as both can provide times for multiple locations at a given instant, potentially confusing an agent.
Most tools follow verb_noun pattern (convert_time, get_current_time, get_dst_transitions, search_cities), but time_by_coordinates deviates by starting with a noun, causing inconsistency.
With 5 tools, the server is well-scoped for a time utility, covering essential operations without being too sparse or excessive.
The tool set covers key time-related operations (current time, conversion, DST, location lookup), but lacks a direct tool for listing timezones or offsets, which is a minor gap.