sim_control

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the mutation/safety profile is partly covered. The description adds the state-transition vocabulary but does not disclose whether 'stop' resets the timeline, whether 'step' advances exactly one frame, or whether any action blocks until completion — meaningful gaps for a control tool even with annotations present.

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?

One short sentence, front-loaded with the resource and immediately followed by the action set. Zero filler and nothing an agent must scan past to find the operative information.

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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. Still, for a simulation-control tool the description omits what each transition actually does to sim state and any preconditions, leaving the agent to guess at the effects of 'stop' and 'step'.

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% and the single 'action' parameter is a closed enum, so the schema already carries the semantics; the description merely restates the four allowed values. Baseline would be 3, but the description's enumeration confirms the enum is exhaustive and complete, adding slight practical value for a 1-parameter tool.

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+resource ('Control simulation') and enumerates the exact operations (play, pause, stop, step), so an agent knows precisely what the tool does. It does not name or distinguish itself from the adjacent sibling get_sim_state, which reads simulation state rather than mutating it, so it falls short of a 5.

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 by the action list: play/pause/stop/step clearly signal the tool is for driving simulation playback. However, there is no explicit guidance on when to use this versus get_sim_state (inspect state) or set_joint_targets (drive motion), and no mention of prerequisites such as needing a loaded scene or paused state before stepping.

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