whatsapp_get_datetime

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

The description discloses the tool returns the current date and time in a specific timezone, which implies a read-only, non-destructive operation. Since no annotations are provided, the description effectively covers the behavioral aspect adequately for a simple getter.

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 concise, with two sentences that efficiently state the purpose and provide a usage hint. No unnecessary words.

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 fully covers the tool's function for a zero-parameter tool with an output schema present. It explains what it returns (date and time in a specific timezone) and why it's useful, leaving no gaps.

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 tool has no parameters, and the description adds meaning beyond the empty schema by specifying the timezone ('Brazil/São Paulo'). With 100% schema coverage and no params, the description usefully clarifies the output 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 clearly states the action ('Get') and the resource ('current date and time'), with specificity ('Brazil/São Paulo'). It distinguishes from all sibling tools, none of which are time-related.

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 know today's date before comparing message timestamps.' This provides clear context, though it does not explicitly mention when not to use or alternative tools.

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