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

With no annotations, the description must carry the full burden of disclosing side effects and behavior. It suggests a read-only, pure operation but does not explicitly state that there are no side effects or explain how the many optional parameters are handled.

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, concise sentence with no unnecessary words. It is well-structured for a tool whose core function is simple.

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 description is incomplete given the complexity of the input schema. It does not explain why the schema includes nine seemingly irrelevant optional parameters, what happens if they are supplied, or what the output format of the timestamp is.

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?

All nine parameters are documented in the schema, so the baseline for this dimension is 3. However, the parameter descriptions are semantically odd and unrelated to 'UTC timestamp', and the tool description adds no clarification about why these parameters exist or whether they are ignored.

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: returning the current UTC timestamp. It is a simple, specific resource/action pairing, though it lacks an explicit verb like 'get' or 'return'.

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 usage guidance is provided. The description implies use when a current UTC timestamp is needed, but it does not mention alternatives like 'timezone' or 'iana-zones', nor does it state when not to use this tool.

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