rhino_polyline

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

The description is consistent with the annotations (readOnlyHint=false implies a mutating create operation, matching 'Add'). It adds the small behavioral detail that the resulting geometry is optionally closed, but discloses nothing else — no mention of layer auto-creation side effects, document targeting via doc_id, or behavior with fewer than two points. No contradiction with annotations.

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 ten words, front-loaded with the verb and object, and contains zero filler. Every word earns its place, and 'optionally closed' is a meaningful qualifier rather than redundancy.

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 creation tool with a well-documented nested schema, an output schema, and annotations covering the read/write nature, the description is minimally adequate. However, it omits any differentiation from the many sibling creation tools and any notes about error conditions (e.g., fewer than 2 points), so an agent would need to rely entirely on the schema for safe 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?

The schema itself carries detailed descriptions for all nested properties (points as 'Ordered vertex list', minItems 2, x/y/z in document units, layer 'created if absent'), so the description's burden is light. The description names the two essential inputs (points and closed) but does not explain the point structure or the args wrapper, so it only partially compensates for the reported 0% schema description coverage at the top level.

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 uses a specific verb ('Add') plus a concrete resource ('a polyline') and an explicit construction method ('through the given points; optionally closed'). It clearly conveys the core operation, though it does not name or differentiate from closely related siblings like rhino_line, rhino_polygon, or rhino_interpolate_curve.

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?

No when-to-use or when-not-to-use guidance is provided. The siblings list contains many similar curve/polyline creation tools (rhino_line, rhino_polygon, rhino_interpolate_curve, rhino_cmd_polyline), and the description gives no criteria for choosing this tool over them, leaving the agent to infer from the name alone.

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