Send input

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

With no annotations, the description carries the behavioral disclosure burden. It clearly discloses that this injects input events and gives stage coordinate ranges. However, it does not describe important behavioral traits like whether inputs are queued, whether they take effect only while the VM is running, or what happens to a pending ask-and-wait prompt.

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 two focused sentences with no filler. The core purpose and input types are front-loaded, and the coordinate-bound detail is placed second where it is relevant to parameter use.

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?

The description is adequate for basic invocation but leaves out operational context: whether the VM must already be running, whether inputs are processed sequentially or batched, how answer interacts with a pending ask-and-wait block, and what the tool returns. These gaps matter more because there is no output schema and no annotations.

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 80%, so the schema already documents the parameters well. The description adds helpful grouping (keys, mouse, answer) and coordinate ranges, but those ranges already appear in the schema. It does not meaningfully elaborate beyond the schema for parameter interpretation.

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 names a specific verb and resource: feed input into the headless VM. It enumerates the concrete input types (key presses, mouse position/clicks, answers to ask and wait), which clearly distinguishes it from sibling VM tools like vm_run, vm_stop, and vm_state.

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 by saying 'the way the editor would,' and it lists the supported input categories. However, it never explicitly states when to use this tool versus alternatives, nor does it mention prerequisites such as the VM needing to be running or a project needing to be loaded.

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