Measure the angle between two planar faces, two lines, or a line and a plane. Supply reference tokens for two elements to get the angle.
Measure the angle between two elements - two planar faces, two lines, or a line and a plane.
| Name | Required | Description | Default |
|---|---|---|---|
| first | Yes | First element reference token. | |
| second | Yes | Second element reference token. |
Changes observed during successful MCP inspections.
v1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds no further behavioral context (e.g., return format, side effects, or prerequisites). It does not contradict annotations, but adds little beyond them.
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 sentence that front-loads the action ('Measure the angle') and immediately provides the specific element types. Every word earns its place, with no 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?
For a simple read-only measurement tool with two parameters and no output schema, the description covers purpose and element types. It does not explicitly state the return value (e.g., angle in degrees), but that is implied by the action. Annotations cover safety, so the definition is nearly complete.
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% with generic 'element reference token' descriptions. The tool description adds meaningful semantics by specifying that the elements can be planar faces, lines, or a line and a plane, clarifying the acceptable input types beyond the schema.
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 (measure) and resource (angle between two elements), and explicitly enumerates the supported element pairs (faces, lines, line-plane). This clearly distinguishes it from sibling tools like catia_measure_distance and catia_measure.
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 specifies the exact element combinations that are valid (two faces, two lines, or line-plane), giving the agent a clear usage context. However, it does not explicitly mention alternatives or when not to use this tool, so it stops short of a 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.