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

With no annotations provided, the description carries the full burden, but it only repeats the tool name. It fails to disclose output behavior, edge cases, or assumptions such as ISO dates or leap-year handling.

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 short but this is under-specification rather than useful conciseness. The single sentence earns no value, as it merely mirrors the tool name.

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 tool with no output schema and no annotations, the description leaves the agent without key information: what value is returned, what date string format is expected, and how this differs from sibling date utilities. The adjacent tools make this ambiguity more problematic.

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%, and the schema describes the date parameter as 'Date to process.' Because the schema already documents the parameter, the description needs no additional parameter detail, though it adds nothing about expected format.

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 is a tautology: 'Day Of Year: Day Of Year' restates the tool name/title and contains no verb, resource, or operational detail. It does not distinguish this from the many sibling date utilities such as week-of-year or julian-day.

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?

There is no guidance on when to use this tool, what date formats it accepts, or how it differs from sibling date tools. The description offers no exclusions or alternatives.

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