get_week_number

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

No annotations are provided, so the description must fully disclose behavioral traits. It states the tool returns 'ISO week number and year' but does not mention edge cases (e.g., date near year boundaries), error handling for invalid dates, or the exact output format. This lack of detail is a significant gap for a simple tool.

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 concise and well-structured: it opens with the main action, then provides usage context and parameter details. Every sentence is necessary, and there is no redundant information.

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?

Given the tool has one optional parameter and an output schema (according to context signals), the description covers the essential aspects: purpose, usage, and parameter explanation. However, it lacks behavioral details such as valid date ranges or what happens with invalid input, which would push completeness to a 5.

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 has 0% description coverage, but the description explains the parameter 'date' with an example format ('e.g. 2025-06-07') and default behavior ('Defaults to today if empty'). This adds meaning beyond the schema, which only has a title and type.

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: 'Get the ISO week number and year for a given date.' It uses a specific verb ('Get') and identifies the resource (ISO week number and year). This distinguishes it from other date-related tools like get_season or calculate_date.

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 context for use: 'Use this to determine the week number of the year following ISO 8601 standards, useful for reporting and scheduling.' It indicates when to use the tool but does not explicitly mention alternatives or when not to use it, which would warrant a 5.

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