create_joint

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

Without annotations, the description discloses behavior comprehensively: explains return values, error cases with conditions, and specific Fusion behaviors (e.g., ball motion ignores axis, accepts only pitch=Z, yaw=X). It also notes persistence of offset_mm across user-param changes.

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 dense but well-organized with bullet-like structure and headers (motion_type, axis, offset_mm, angle_deg, name, Errors). It's slightly long but each sentence adds value; no fluff.

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's complexity (7 params, no annotations, no output schema), the description is exceptionally complete: covers usage, parameter semantics, return format, error modes, and integration with other tools. It enables an agent to invoke correctly without external references.

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 0%, but description covers all 7 parameters with practical details: geometry handles and kinds, motion_type values and DOF, axis relative to local frame, offset_mm with example usage, angle_deg for specific motions, and name. This fully compensates for the schema gap.

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 clearly states the tool creates a joint between two entity handles, specifies supported entity kinds and motion types, and provides detailed examples. It effectively distinguishes from sibling tools like drive_joint and set_joint_limits by noting the joint_name is used for downstream calls.

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?

Provides explicit guidance on when to use: specifies handle formats, which tools to get handles from, and explains motion types with analogies (e.g., revolute for hinges). It also mentions when not to use (e.g., Axis ignored for ball) and how offset_mm is preserved unlike Move-based positioning.

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