list_faces

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

No annotations are provided, so the description carries the full behavioral burden. It does disclose the compact output format and min_area filtering, but it omits read-only status, max_count truncation behavior, error conditions, and instance handling details.

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?

Two compact sentences with the output format front-loaded and no wasted phrasing. The example line is useful, though the opening is dense and assumes familiarity with the face-table notation.

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?

The tool is simple and has an output schema, and the description gives the return-line format plus min_area meaning. Still, it leaves max_count/truncation behavior and 'body 1' ambiguous, which are relevant for correct invocation.

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 low at 33%; instance is described in the schema, and the description explains min_area as an mm² filter for small faces. However, max_count is not explained in either the schema or the description, so compensation for the low coverage is only partial.

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?

States a specific verb and resource (list faces) and includes an output-line example plus intended use for sketching/cuts. It does not distinguish itself from siblings such as find_face or assembly_faces, and 'body 1' is unexplained.

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?

Says to use it to locate faces for sketching/cuts and notes that min_area filters small faces, which gives implied usage context. It does not say when to choose this over find_face, assembly_faces, or list_edges, nor does it state prerequisites or exclusions.

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