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

With no annotations provided, the description carries the full burden of behavioral disclosure. It simply states 'Current time' without detailing output format, error handling, or the fact that only the 'zone' parameter is used while others are discarded. The schema's parameter descriptions hint at this, but the tool description itself omits it.

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. However, it under-specifies by not clarifying the key parameter, which could be seen as too terse for a tool with nine parameters.

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 tool appears simple, but the schema is cluttered with irrelevant parameters that are marked as discarded. The description doesn't clarify that only 'zone' matters, making it incomplete for an agent trying to call the tool correctly. Without an output schema or annotations, the agent has insufficient context.

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 the schema documents all parameters. The description adds no parameter-level information beyond what's in the schema, earning the baseline score of 3.

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 tool's function: returning the current time for a given IANA timezone. It is distinct from sibling tools like utc-time and iana-zones, though it doesn't explicitly mention alternatives. However, the schema includes many unrelated parameters that could confuse an agent about the tool's actual input, reducing clarity slightly.

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 versus alternatives like utc-time. It doesn't mention any conditions or exclusions, leaving the agent to infer usage from the name and description alone.

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