create_rigid_groupLock multiple Fusion 360 components together into a rigid group by specifying their names; optionally include child sub-components to keep assemblies fixed.
Lock multiple components together
| Name | Required | Description | Default |
|---|---|---|---|
| component_names | Yes | Names of components to group | |
| include_children | No | Include child sub-components |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations indicate this is a non-read-only, non-idempotent, non-destructive operation, which the description aligns with by implying a creation action ('Lock'). The description adds minimal behavioral context beyond annotations—it hints at grouping behavior but doesn't detail effects like persistence, reversibility, or interaction with other operations. No contradiction with annotations exists.
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 a single, efficient sentence with zero wasted words—'Lock multiple components together' directly conveys the core action. It's front-loaded and appropriately sized for the tool's complexity, making it easy 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?
Given the tool has no output schema and annotations cover basic safety (non-destructive), the description is minimally adequate. It states the purpose but lacks details on behavioral outcomes, error conditions, or integration with sibling tools. For a creation tool with 2 parameters, it meets a bare minimum but doesn't provide rich contextual guidance.
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%, with clear parameter documentation: 'component_names' (array of strings, min 2 items) and 'include_children' (boolean, default true). The description 'Lock multiple components together' loosely relates to 'component_names' but adds no specific semantics beyond the schema, such as format examples or grouping implications. Baseline 3 is appropriate given high schema coverage.
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 'Lock multiple components together' clearly states the tool's function with a specific verb ('Lock') and resource ('components'), and the 'rigid' aspect is implied. However, it doesn't explicitly differentiate from sibling tools like 'create_component' or 'add_joint', which could also involve component relationships, leaving some ambiguity about its unique role.
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 provides no guidance on when to use this tool versus alternatives. With many sibling tools like 'create_component', 'add_joint', or 'boolean_operation' that might handle component interactions, there's no indication of specific use cases, prerequisites, or exclusions for 'create_rigid_group'.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.