Current Date/Time

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

With no annotations, the description carries the full burden and does disclose the core behavior: it returns the current date and time adjusted for a given timezone. However, it does not specify the output format (e.g., ISO 8601 string, offset inclusion) and there is no output schema to fill that gap.

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, efficient sentence with no filler. The action and the key scoping condition are both front-loaded, making it easy for an agent to parse quickly.

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 simple one-parameter, read-only utility, this description is nearly complete: an agent knows what input to supply and what kind of result to expect. The only notable gap is the exact return format, which is minor given the simplicity of the tool.

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 input schema fully describes the single required parameter, including IANA timezone examples. The description adds no additional parameter semantics, but since schema description coverage is 100%, the baseline of 3 applies.

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 uses a specific verb ('Return') and names a clear resource ('current date and time'), then scopes it to 'a given IANA timezone.' This clearly differentiates it from unrelated siblings like calculator, hash, and base64.

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 makes the usage context clear: use this tool whenever you need the current date and time for a specific IANA timezone. It does not explicitly discuss exclusions or alternatives, but none of the sibling tools perform time-related operations, so no further guidance is necessary.

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