Cyclomatic complexity per function

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

With no annotations, the description carries the burden of behavioral disclosure. It explains what the metric approximates, what counts as a decision point, and that results are sorted. It does not detail whether the file must be indexed or whether large files may be slow, but for a read-only analysis tool, this is reasonable.

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?

One efficient, well-structured sentence states the metric, the decision points, the scope, and the sort order. Every part adds information and no words are wasted.

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 only two simple parameters and no output schema, the description covers the essential behavior. It could mention whether 'file' refers to a workspace-relative path or an absolute path, and could hint at the output shape, but those are minor gaps given the tool's simplicity.

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 coverage is 100%, so the schema already documents the 'file' and 'language' parameters. The description adds value by clarifying that the file is a source file and that the analysis is per function, which is not stated in the parameter descriptions. The language enum is self-documenting.

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 the tool computes approximate cyclomatic complexity per function in a source file, sorted worst first, and explicitly defines the formula. This makes the tool's purpose clear and distinguishes it from sibling tools like ast_search or find_references, which do different things.

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 gives clear context for use: analyzing a source file for complexity metrics, with an optional language override. It does not explicitly name sibling alternatives or give when-not-to-use guidance, but the context is specific enough that an agent can infer when to use it.

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