Current Time

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds the crucial detail of the return format (RFC3339 string) with an example, which is beyond what annotations provide. It does not contradict annotations and gives the agent the exact expected output shape, though it could have mentioned that the tool has no side effects, but that's already implied by annotations.

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, information-dense sentence that states the purpose, the exact output format, an example, and the recommended usage scenario. Every word earns its place, and the most important information (output format and usage) is front-loaded.

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?

For a zero-required-parameter tool with no output schema, the description provides all necessary context: it tells the agent what it returns (UTC time in RFC3339), gives an example, and explains when to use it. There is nothing an agent needs to know to call this tool correctly that is missing. The annotations cover the safety profile, so the description is complete for its simplicity.

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 only parameter is _jq, and the schema covers it 100% with a thorough description. The tool description adds no parameter-specific information, but with full schema coverage, a baseline of 3 is appropriate. The description's main focus is on the return value, not parameters, and that's acceptable since the schema handles it.

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 gets the current UTC time as an RFC3339 string with an explicit example. It is specific about the verb, resource, and output format, and it is distinct from all sibling tools since none deal with time retrieval.

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 explicitly states when to use this tool: 'Use to determine current date/time before making date-based queries.' This gives a clear, actionable usage scenario. While no alternative is mentioned, that is appropriate because no sibling tool serves the same purpose, and the guidance fully covers the intended use.

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