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, and it discloses nothing. The name weakly implies a pure read-only calculation with no side effects, but there is no statement about return format, optional/omitted year behavior, or edge cases such as leap years.

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?

It is short, but that shortness reflects under-specification rather than conciseness: the same phrase is duplicated twice and encodes no information. There is nothing to front-load because there is no content.

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 trivial one-parameter calculation with no output schema, an agent still needs to know the return value and the accepted year format, and to distinguish this tool from the cluster of week/date siblings. None of that is provided.

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?

There is a single parameter with 100% schema description coverage, so the schema already documents it; per the baseline rule this yields a 3. The description adds no meaning beyond the schema and does not clarify the expected year 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?

"Weeks In Year: Weeks In Year" is a tautology that merely restates the tool name/title. It never states the verb or what is actually returned (a count? a list of week numbers?), and it does nothing to distinguish itself from siblings such as x402-days-in-year, x402-week-of-year, or x402-week-number.

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 versus the many adjacent week/date tools in the sibling set. No context, no prerequisites, no exclusions are offered.

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