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

No annotations are present, so the description carries the burden, but it does not disclose whether parameters are ignored, whether side effects occur, or whether the tool requires network access. The schema's oddly unrelated parameters make this omission especially problematic.

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 phrase with no filler. It front-loads the key fact that the tool provides the current UTC timestamp.

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 too sparse given the unusual 9-parameter schema and the absence of an output schema. It does not explain why those parameters exist, whether they affect the result, or what format the timestamp is returned in.

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?

Although the schema has 100% description coverage, the parameters are unrelated to returning a UTC timestamp and the descriptions do not tie them to the tool's function. Some, like 'zone', could mislead an agent into thinking timezone conversion is supported.

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 'Current UTC timestamp' clearly identifies the resource and distinguishes the tool from siblings like timezone and iana-zones. It lacks an explicit verb such as 'returns' or 'gets', but the intent is still unambiguous.

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 given about when to use this tool instead of timezone, iana-zones, or other time-related tools. The description provides no conditional context or alternatives.

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