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

With no annotations, the description must carry the behavioral burden. It implies a read-only operation, but it does not disclose that all seven parameters are discarded, nor does it specify the return format (Unix timestamp vs. ISO string). These are important behavioral details for an agent.

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 three words and contains no filler. It is front-loaded and appropriately sized for a simple utility, even though additional guidance could improve other dimensions.

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 no output schema, no annotations, and a non-obvious seven-parameter input list, the description is too terse. It does not state the exact return representation or explicitly clarify that parameters do not affect the result. The schema partially compensates, but the overall definition is incomplete.

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 schema itself provides detailed descriptions for all parameters, including notes on discarding and no disk access, so schema coverage is high and the baseline is 3. The tool description adds no parameter-related meaning, but the schema already does the necessary work.

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 resource and result: a current UTC timestamp. It is unambiguous and distinguishable from sibling tools like timezone or iana-zones. It lacks an explicit verb, but the meaning is specific enough for an agent to understand the tool's purpose.

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?

There is no explicit guidance about when to use this tool versus alternatives like timezone. The word 'current' implies a clock lookup, but no conditions, exclusions, or alternative tool references are provided.

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