Type text into browser input, textarea, or contenteditable fields, replacing value or typing slowly; submit with Enter.
Type into an input/textarea/contenteditable. Replaces its value unless slowly: true (types key by key). submit: true presses Enter.
| Name | Required | Description | Default |
|---|---|---|---|
| ref | No | Element ref from browser_snapshot, e.g. "e12" | |
| text | Yes | ||
| slowly | No | ||
| submit | No | ||
| selector | No | CSS or Playwright selector (alternative to ref) |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare destructiveHint=true, but the description is what explains why: the default behavior replaces the field's existing value, and only slowly:true preserves key-by-key entry. It also discloses that submit:true fires Enter, a side effect not captured by annotations. Focus/permission requirements remain unmentioned.
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?
Three tight clauses with no filler, and the destination plus the default overwrite behavior are front-loaded. The telegraphic 'slowly: true' shorthand is compact but slightly cryptic without a comma-joined explanation.
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 5-parameter mutation tool with annotations and no output schema, the description covers the main non-obvious behaviors (overwrite default, slow typing, Enter submission). It omits failure handling and ref-vs-selector precedence, which are minor given the schema already defines both targeting options.
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 only 40% and slowly/submit have no schema descriptions, yet the description supplies their exact semantics (slow = per-key typing, submit = Enter press) plus the default replace behavior of text. ref and selector are already documented in the schema, so the remaining gap is small.
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 (type) and the exact target set (input/textarea/contenteditable), which is more precise than the tool name alone. It does not name a sibling or draw an explicit boundary against browser_press_key or browser_click, so it stops 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 target-element list, and the slowly/submit flags hint at when each mode applies (character-by-character vs instant, Enter submission). There is no explicit when-to-use/when-not guidance and no routing to browser_press_key for plain key presses.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.