Evaluate a curve at a given parameter to retrieve its exact position and tangent vector for geometric analysis and modeling decisions.
Evaluate position and tangent at a parameter on the curve.
| Name | Required | Description | Default |
|---|---|---|---|
| args | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint and idempotentHint annotations already establish that this is a safe, deterministic query. The description adds the position/tangent behavior but does not discuss out-of-domain parameters, tangent normalization, or error behavior; these are partly covered by the schema and output schema.
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?
A single front-loaded sentence with no wasted words: it states the operation and outputs before the parameter context. It is easy for an agent to parse quickly.
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 curve evaluation, annotations cover safety, the output schema covers the return shape, and the schema covers the parameter and object identity. Nothing essential for correct invocation is missing.
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 nested input schema already documents object_id as a curve GUID, t as a parameter within Domain, and doc_id as a document handle. The description adds no extra parameter-level meaning beyond 'at a parameter,' so the baseline of 3 applies.
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 ('Evaluate'), the exact output ('position and tangent'), and the resource ('a curve'). This clearly distinguishes it from curve length, splitting, or surface-evaluation siblings.
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?
Usage is implied: an agent should call this when it needs a point and tangent on a curve at a parameter. However, there is no explicit when-to-use/when-not-to-use guidance or named alternative tool, so it stops short of 4.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.