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

The description is minimal and does not disclose whether parameters are accepted or ignored. The schema lists unrelated optional parameters, creating ambiguity about the tool's actual behavior.

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 very short and avoids fluff, but it may be too terse given the mismatched schema. Additional context about parameters would improve usefulness without sacrificing conciseness.

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?

The tool is incomplete in context: the schema seems copied from other tools, and the description does not reconcile this. There is no output schema or parameter guidance, leaving significant ambiguity for an agent.

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?

The description adds no meaning to the schema parameters. The schema properties (url, host, json, zone) appear unrelated to a UTC timestamp tool, and the description does not clarify their role.

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 current UTC timestamp, which distinguishes it from related timezone tools. It is concise and specific, though it lacks an explicit verb.

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 is provided about when to use this tool versus alternatives like timezone or iana-zones. The description does not mention any selection criteria or context.

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