Draw a spline through a list of [x, y] control points in millimeters, with an option to close the curve.
Draw a spline through a list of control points. Each point is [x, y] in mm.
| Name | Required | Description | Default |
|---|---|---|---|
| closed | No | Whether to close the spline (default: false) | |
| points | Yes | List of [x, y] control points in mm |
Changes observed during successful MCP inspections.
v0.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=false, and idempotentHint=false, so the agent knows this is a non-destructive write operation. The description adds useful point format and unit context, but it does not disclose whether an active sketch is required or what side effects occur. With annotations covering the safety profile, this is adequate but not rich.
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 two short sentences with no wasted words. It leads with the primary action and follows with the point format, making it well-structured for quick agent consumption.
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 sketch primitive with annotations and full schema coverage, the description covers the core action and point units. It omits important contextual details such as whether an active sketch is required and how it relates to the sibling GSD spline tool. It is minimally adequate but not fully 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 description coverage is 100%, and the input schema already documents both points and closed with clear descriptions. The description repeats the point format and millimeter units rather than adding meaning beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.
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: 'Draw a spline through a list of control points.' It distinguishes this from most sketch primitives like line, circle, and rectangle. However, it does not explicitly distinguish sketch splines from the sibling catia_gsd_spline, so sibling differentiation is incomplete.
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 only says what the tool does, not when to use it. It gives no prerequisites, no when-not conditions, and no alternative tools such as catia_gsd_spline. The agent must infer usage context from the tool name or surrounding workflow.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.