cosine

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

With no annotations, the description carries the behavioral disclosure burden, and it does add one useful behavioral detail: angles are degrees by default. However, it does not explicitly describe what happens when the 'degrees' parameter is false, nor any other behavioral traits such as return value shape, though the output schema partially covers that.

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 concise, front-loaded sentence: 'Calculate cosine' leads with the core purpose, and the unit clarification follows immediately. Every word earns its place.

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 simple pure-math tool with only two parameters and an output schema, the description plus schema is largely sufficient. The only notable gap is that the radians behavior is not explicitly spelled out, but the 'degrees' boolean and its default make it reasonably inferable.

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 0%, so the description must compensate. It provides the key semantic detail that angles are degrees by default, which clarifies the 'angle' parameter's unit. It does not explicitly explain the 'degrees' boolean beyond the default, but the parameter name and schema default make the intended behavior fairly clear.

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 specific operation ('Calculate cosine') on a clear resource, which distinguishes it from sibling trigonometric tools like sine and tangent. It could be slightly stronger by explicitly referencing the input angle, but the meaning 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 is provided about when to use this tool versus alternatives such as sine or tangent. The description only states what the tool does, leaving the agent to infer selection purely from the tool name.

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