set_joint_command

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

With no annotations, the description carries the full burden of behavioral disclosure. It reveals that the operation is atomic, that selectors/values are pre-validated and that invalid inputs apply nothing, and that effort commands are one-shot. It does not describe whether position/velocity commands persist across steps or the meaning of idempotency_key, but the disclosed traits are substantive.

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 well-structured: a one-sentence purpose, then the critical behavioral caveats, then a compact Args list. Every sentence adds value, and important details like atomicity and effort renewal are front-loaded.

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 7-parameter tool with no annotations, the description covers the core semantics, validation failure behavior, effort renewal, and selector constraints. Gaps remain for command_id and idempotency_key, and for whether position/velocity commands persist, so it is not fully complete, but it is strong enough for an agent to safely invoke the tool.

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 0%, so the description must compensate. It does add meaning for prim_path, mode (position/velocity/effort), values (ordered by selected joints), joint_names (exact, case-sensitive subset), and joint_indices (mutually exclusive with joint_names). Yet it omits command_id and idempotency_key, leaving two parameters semantically unexplained.

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 opens with a specific verb and resource: 'Apply an atomic position, velocity, or effort joint command.' This clearly identifies the tool's function and distinguishes it from sibling tools like set_joint_positions, which only handle positions, and set_joint_drive_config, which configures drive settings rather than issuing commands.

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 important usage context for effort mode — commands must be renewed each simulation update and this tool applies one update's effort command. However, it does not explicitly contrast this tool with alternatives such as set_joint_positions or plan_joint_trajectory, so an agent must infer when to choose this tool over the available siblings.

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