Select and click a specific element in Chrome by its numbered index from a prior accessibility read, enabling targeted interaction with Android browser content.
Click an element by its number from chrome_read.
| Name | Required | Description | Default |
|---|---|---|---|
| index | Yes | ||
| device | No | ||
| tab_id | No |
| 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 provided, the description carries the full burden of behavioral disclosure. It states only the immediate click action and does not mention potential side effects such as navigation, page changes, waiting, or whether the click may trigger destructive actions. For a click operation this is a significant transparency gap.
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 a single sentence with no filler, extraneous detail, or repetition of schema information. The key action and source are front-loaded, making it easy to parse quickly.
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 tool with no annotations, an output schema, and three parameters, the description is too thin. It lacks parameter guidance for device and tab_id, does not explain when to use this tool over alternatives, and omits behavioral side effects that matter for an agent deciding whether clicking is safe or appropriate.
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 0%, so the description must compensate for all parameters. It clarifies that 'index' is the element number from chrome_read, but it gives no meaning for 'device' or 'tab_id', leaving two of three parameters unexplained and relying on the agent to infer their purpose.
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 action ('Click an element') and the resource ('by its number from chrome_read'), making the tool's purpose immediately understandable. It implicitly distinguishes itself from generic tap tools by tying clicks to numbered elements from chrome_read, but it does not explicitly name sibling alternatives.
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 phrase 'from chrome_read' implies a precondition: the agent must first call chrome_read to obtain numbered elements. However, it gives no explicit guidance about when to choose this tool over siblings like tap, tap_coordinates, or tap_text, and provides no 'when not to use' conditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.