Execute click, type, or select actions on indexed browser elements using an action_id from jev_observe; provide text for fill actions.
Execute an action on an element. Use action_id from jev_observe.
Args: action_id: Element ID from jev_observe (e.g., 'e1', 'e2') text: Text to type (required for fill actions)
| Name | Required | Description | Default |
|---|---|---|---|
| text | No | ||
| action_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It discloses that text is required for fill actions and that action_id comes from observation, but says nothing about side effects, waiting behavior, error handling, or reversibility—significant gaps for a mutating execute tool.
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?
Front-loads the purpose, then the prerequisite, then a compact Args block that is necessary given zero schema descriptions. Every sentence earns its place with no filler.
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?
An output schema exists, so return values need not be explained. The description covers purpose, prerequisite, and parameters, but leaves action types and behavioral traits underspecified, which matters for an execute tool with 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 0%, so the description must compensate. It explains action_id as an element ID from jev_observe with examples ('e1','e2') and text as required for fill actions, adding real meaning beyond the bare schema. It leaves action-type mapping somewhat implicit.
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 ('Execute'), resource ('an action on an element'), and ties the action_id to sibling tool jev_observe, distinguishing it as the acting counterpart to observing. It does not enumerate action types, but the core purpose is clear.
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?
'Use action_id from jev_observe' gives the prerequisite and workflow relation, making it clear this tool is used after observing. It stops short of explicit when-not guidance or naming alternative siblings like jev_navigate.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.