Simulate keyboard input such as Enter, Escape, Tab, or Control+A in a webview, optionally targeting an element by selector or snapshot ref.
Press a key, e.g. Enter, Escape, Tab, Control+a.
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | ||
| ref | No | ref from snapshot, e.g. e3 | |
| tab | No | tab id, defaults to current | |
| selector | No | CSS selector | |
| request_timeout | No | Outer page request deadline in milliseconds; defaults to at least 30000 |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations, so the description carries the entire burden, and it discloses almost no behavior: nothing about whether the key goes to the page, the focused element, or the element identified by ref/selector, nor what happens on failure or timeout. Only the key format is conveyed.
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?
A single front-loaded sentence with zero filler. It is efficient, though arguably so terse that conciseness shades into under-specification.
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 five-parameter input tool with no annotations and no output schema, the description leaves important behavior undefined: which element receives the key, how ref/selector/tab interact, and whether an error is returned if the target is missing.
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 ref, tab, selector, and request_timeout, establishing the baseline of 3. The description's examples add genuine meaning for the required key parameter (key-combo syntax like 'Control+a'), but the targeting parameters are not clarified further.
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?
States a specific verb and resource ('Press a key') with concrete examples of key values, so the agent knows this is keyboard input rather than text entry. It doesn't explicitly contrast with the close siblings 'type' and 'fill', which is the main gap.
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 examples (Enter, Escape, Tab, Control+a) imply shortcut/mnemonic use versus typing content, which is useful implicit guidance. There is no explicit statement of when to use this instead of 'type'/'fill', or prerequisites such as needing an element focused first.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.