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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says 'Current time' without specifying return format, network dependencies, rate limits, or side effects. It also doesn't clarify that only the 'zone' parameter is relevant, despite the schema containing 8 unrelated parameters.

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?

A single, front-loaded sentence with zero wasted words. It states exactly what the tool does in the fewest possible words. No redundancy or filler.

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 is inadequate for a tool with 9 parameters and no output schema. It doesn't specify the return format, whether it includes date or offset, or which parameters actually affect the result. The presence of many unrelated parameters adds confusion. The description should clarify the tool's scope and output but does not.

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?

Schema description coverage is 100%, so every parameter has a description. The relevant 'zone' parameter is described as 'IANA timezone name', which is clear. However, the description adds no parameter info beyond the schema and doesn't indicate that the other 8 parameters are ignored. Baseline 3 applies due to high schema coverage.

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 states a clear verb+resource: returns current time for a named IANA timezone. It distinguishes itself from siblings like utc-time and iana-zones, though not explicitly. The purpose is unambiguous.

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 like utc-time or iana-zones. The description provides no conditions, exclusions, or routing advice. Usage context is left entirely to the agent's inference.

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