find_face

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the return type, default min_area filtering for tiny edge faces, and default centroid tolerance, but it omits important behavior such as what happens when no face or multiple faces match.

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 short, front-loaded with purpose and return value, and uses a clean Args block for parameter meanings. Every sentence adds useful information with no repetition or filler.

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?

An output schema exists, so return-value details need not be expanded. For a 9-parameter search tool with no annotations, the description covers the core matching behavior well, though it could mention coordinate frame assumptions or no-match/multi-match behavior.

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 only 11%, so the description must explain parameters, and it does: x/y/z are target centroid coordinates, use_x/y/z control which coordinates are matched, and min_area/tolerance have defaults and purpose. The instance parameter is documented in the schema rather than the description, which is a minor gap.

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 verb and resource: "Find a planar face by its centroid coordinates (mm)," and it explicitly says it returns a face index string. It is clear about what the tool does, but it does not explicitly contrast itself with siblings such as list_faces or find_edge.

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?

It gives a concrete usage context: sheet metal Cut, locating the outer panel face to sketch on. That is clear guidance for when the tool is useful, though it does not state when not to use it or name alternative tools for other face-finding cases.

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