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

No annotations are provided, so the description must fully disclose behavior. It only states the output (UTC timestamp) and says nothing about side effects, parameter handling, or limitations. The schema hints that many parameters are discarded, but this is not surfaced in the description, leaving the agent uninformed about 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 extremely brief—only four words—which is concise but under-specified for a tool with 9 parameters and no annotations. It is not front-loaded with useful context, and the minimalism results in a lack of necessary information rather than efficient communication.

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 complexity of 9 parameters and the absence of annotations or an output schema, the description is woefully incomplete. It does not explain how parameters affect the result, what the return format is, or when to use the tool. An agent cannot confidently call this tool correctly based on the description alone.

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?

Schema description coverage is 100%, so the schema already documents each parameter. The description adds no parameter-level meaning and does not explain why 9 diverse parameters are relevant to a UTC time tool. Baseline of 3 is appropriate since the schema carries the weight, but the description fails to clarify the purpose of these parameters in context.

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 states the tool returns the current UTC time, which is a specific resource. However, it does not distinguish itself from sibling tools like 'timezone' or 'iana-zones', and lacks an explicit verb like 'get' or 'return', so it falls short of a 5.

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. It does not mention any context, exclusions, or comparison to sibling tools such as 'timezone' or 'normalize-url'. The agent is left without direction on selection.

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