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

With no annotations, the description carries the full burden of behavioral disclosure. It does not mention that the tool accepts nine parameters that are effectively discarded, nor does it specify the output format (e.g., ISO string vs. Unix timestamp). This is a significant gap for a tool with an unusual parameter set.

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, but it is under-specified. It does not front-load critical information such as the ignored parameters or the return format. The brevity is not backed by substantive content, making it less helpful than it could be.

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 has nine parameters, no output schema, and no annotations, the description is incomplete. It fails to explain the purpose of the parameters, the exact nature of the returned timestamp, or any side effects. An agent cannot fully understand how to invoke it correctly without additional information.

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 input schema already provides detailed descriptions for all parameters, including notes that they are discarded after checks. The tool description adds no additional meaning beyond the schema, so it does not improve on the baseline score of 3 for high schema coverage.

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 states 'Current UTC timestamp,' which clearly identifies the tool's purpose as returning the current UTC time. However, it does not differentiate it from sibling tools like 'timezone' or 'iana-zones' that also relate to time.

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 no guidance on when to use this tool versus alternatives such as 'timezone' or 'iana-zones.' There is no mention of use cases, exclusions, or when other tools would be more appropriate.

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