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

With no annotations and a minimal description, there is no disclosure of side effects, read-only status, authentication requirements, or error behavior. The agent cannot infer whether the tool is safe, reversible, or if it might fail under certain conditions.

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 exceptionally concise—a single sentence that conveys the core functionality without extraneous detail. No wasted words or redundant phrasing.

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 fails to explain why the tool accepts parameters like url, host, json, and zone, which are clearly irrelevant to generating a UTC timestamp. This severe mismatch leaves the tool's purpose and usage context incomplete and confusing, potentially leading to incorrect invocations.

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 lists four parameters (url, host, json, zone) with descriptions that appear arbitrary and unrelated to a UTC timestamp tool. Each description suggests a different purpose (e.g., 'HTTPS URL to normalize or cite'), creating complete confusion about what inputs are actually expected or how they affect the output.

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's function in a single, unambiguous phrase. It specifies both the action (current) and the output format (UTC timestamp), leaving no doubt about 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?

The description provides no guidance on when to use this tool or alternatives. There is no mention of conditions, prerequisites, or comparison with sibling tools like 'timezone' or 'validate-json', leaving the agent without context for selection.

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