Press a key or keyboard shortcut on the focused browser element to trigger actions like Enter, Escape, Tab, or Control+A during automation.
Press a key or combo on the focused element (e.g. Enter, Escape, Tab, Control+A). Like Claude press_key.
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | Key or combo: Enter, Escape, Tab, ArrowDown, Control+A, Meta+C, ... | |
| session | No | Per-call session override (does not change the process default) |
Changes observed during successful MCP inspections.
v1.3.0Does 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 does not mention what happens if no element is focused, whether the key press triggers navigation or events, or any side effects. The comparison to Claude press_key is vague and doesn't reveal concrete behavior.
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 concise and front-loaded with the action ('Press a key or combo'). The reference to 'Like Claude press_key' is short but may be unnecessary for an agent unfamiliar with Claude. Overall, it is efficient with minimal waste.
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?
Given no annotations, no output schema, and a simple 2-parameter schema, the description is too sparse. It does not explain expected return values, errors (e.g., no focused element), or how the 'session' parameter affects behavior. The tool is simple, but the description lacks context needed for reliable invocation.
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 schema already documents both 'key' and 'session' with examples. The description adds the phrase 'on the focused element' but does not provide additional semantics beyond schema. Baseline 3 is appropriate since the schema does the heavy lifting.
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 presses a key or combo on the focused element, with specific examples (Enter, Escape, Tab, Control+A). This distinguishes it from sibling tools like wb_click or wb_fill, but the reference 'Like Claude press_key' is slightly ambiguous and doesn't explicitly differentiate from all siblings.
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?
No explicit guidance on when to use this tool versus alternatives. The phrase 'on the focused element' implies it is for keyboard interactions, but there is no mention of prerequisites, exclusions, or when to prefer wb_click or wb_fill. The 'Like Claude press_key' comparison is not a practical usage guideline.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.