simulate_input

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses the basic action (injecting input) but does not explain side effects, error conditions, or runtime requirements (e.g., whether a scene must already be running headlessly, what happens if the injection fails). There is no mention of return values or output, leaving the agent without critical behavioral context.

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, concise sentence that immediately conveys the core purpose. It is well front-loaded and contains no filler or redundant 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?

Despite having 7 parameters, no output schema, and no annotations, the description provides only the barest functional overview. It does not explain essential context such as the relationship between scenePath and a running scene, the meaning of durationFrames, or the distinction between key and mouse_button events. The tool would be difficult to invoke correctly without additional information.

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 only 14% (only projectPath is described), so the description must compensate. However, it only mentions 'keyboard or mouse input event', which maps to the eventType parameter, but fails to explain keycode, buttonIndex, pressed, durationFrames, or scenePath. These parameters remain semantically opaque, and the description adds minimal value beyond the schema.

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's function: 'Inject a keyboard or mouse input event while a scene runs headlessly.' It uses a specific verb ('inject'), names the resource ('keyboard or mouse input event'), and provides a context ('while a scene runs headlessly'). This distinguishes it from sibling tools like run_automation_test or capture_screenshot, which have different purposes.

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 implies usage during a headless scene run but provides no explicit guidance on when to use this tool versus alternatives. It does not mention any prerequisites, such as a scene currently running, nor does it compare to related tools like run_automation_test or run_project. The user is left to infer the intended automation/testing context.

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