Convert a watertight surface into a solid. Ensure surface pieces are joined and healed to bound a closed volume before closing.
Close a watertight surface into a solid. The surface must bound a closed volume, so join and heal the pieces first if needed.
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | Name for the resulting feature. | |
| surface | Yes | Reference token of the closed surface. |
Changes observed during successful MCP inspections.
v1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=false and destructiveHint=false, so the agent knows this is a modifying operation. The description adds the precondition of watertightness and the tip to join/heal first, which is useful context. However, it doesn't describe the exact result or side effects, but given annotations cover the safety profile, this is adequate.
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 one concise sentence that front-loads the action, states the condition, and offers a practical tip. No redundancy or wasted words.
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 operation with no output schema, the description provides the essential precondition (watertight) and a remediation tip (join/heal). It's complete enough for an agent to know when and how to use it. Minor gap: it doesn't explicitly state that the result is a new solid feature, but that's implied by 'into a solid'.
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 both parameters (name and surface) having descriptions. The description doesn't add parameter-specific details but provides context about the surface needing to be watertight, which is relevant. Baseline 3 is appropriate since 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 'close' with a specific resource 'watertight surface' and result 'solid'. It clearly distinguishes from sibling tools like join and heal by defining the condition that must be met, making the tool's unique purpose unambiguous.
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 explicitly advises to 'join and heal the pieces first if needed', which implies when to use this tool (only on watertight surfaces) and when not to (when surface is not watertight). While it doesn't name alternative tools, the reference to join and heal serves as clear guidance for preparation.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.