Sketch arbitrary entities

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

Annotations provide no read-only or destructive hints, so the description carries the behavioral burden. It clearly indicates that the tool creates/adds a sketch and adds the useful closed-profile constraint, but it does not disclose side effects like feature-tree insertion, error behavior, or what happens with an open 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?

Three short sentences with no filler. The core purpose is front-loaded, the usage condition is stated next, and the extrusion tip is a practical final note. Every sentence earns its place.

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 schema fully documents all 8 parameters, and the description covers tool selection plus a critical geometric constraint. It lacks explicit return/error information, but with no output schema and a fully covered input schema, the essential invocation context is present enough for an agent to proceed.

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%, so the baseline is 3. The description adds semantic value beyond the schema by emphasizing that the profile should be closed if extruding and by implicitly framing entities as the core payload. It does not need to repeat parameter details the schema already documents.

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 action and resource: "Add a sketch from a list of entities: lines, circles, rectangles and arcs." It also distinguishes this tool from "single-shape sketch tools," so an agent can immediately tell it apart from onshape_sketch_line, onshape_sketch_circle, and onshape_sketch_rectangle.

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 explicit selection guidance: "Use this when the single-shape sketch tools cannot express the profile." It also adds a conditional follow-up instruction about closing the profile before extruding, which helps the agent use the tool correctly in a downstream workflow.

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