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

No annotations are provided, so the description must fully convey behavior. It only states the basic purpose, omitting details like timezone handling (despite 'tz' parameter), output format, and whether it returns a string or object. The default timezone behavior is unmentioned.

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 short and front-loaded, making it easy to parse. However, it sacrifices important details for brevity. While concise, it is arguably too sparse for a tool with a parameter and no annotations.

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 tool has one optional parameter and no annotations, the description should provide more context (e.g., return format, timezone handling). An output schema exists, but the description doesn't leverage it. The tool is simple, but the description is still 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 description does not mention the 'tz' parameter, but the input schema already provides a clear description ('Timezone (UTC, America/New_York, etc.)') and a default value. With 100% schema coverage, the description adds no additional meaning, so baseline of 3 is appropriate.

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 'Get current date and time.' clearly states the action and resource, but it is very minimal and does not distinguish from sibling tools like 'current_time' or 'date_to_timestamp'. The lack of details about return format or context reduces clarity.

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 on when to use this tool versus alternatives. With many time-related siblings (e.g., 'current_time', 'unix_to_datetime'), the absence of usage context makes selection harder. No prerequisites or exclusions mentioned.

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