DESKTOP browser on the testing grid — NOT a phone or tablet. Opens a page and navigates to a URL, returning a pageId that every other web_* tool takes. To drive the browser ON A REAL DEVICE instead, use the webpage_* tools, which take a udid.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | URL to navigate to | |
| browser | No | Browser to use: chrome | firefox | safari (default: chrome) |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the behavioral burden. It discloses the desktop grid environment, the navigation action, and the pageId return contract. It does not discuss side effects beyond navigation, but for this tool the core behavior is stated clearly enough.
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 sentences with no filler. The critical differentiator (desktop, not phone/tablet) is front-loaded, and the return contract and alternative tool path are stated efficiently.
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?
The tool is simple, both parameters are fully documented in the schema, and the description covers the output contract and the main alternative. Nothing essential is missing for correct 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%, so the schema already documents url and browser fully. The description adds no new parameter-level meaning beyond mentioning URL navigation, making the baseline 3 appropriate.
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?
Clearly identifies the action (navigates to a URL), the target context (DESKTOP browser on the testing grid, not a phone/tablet), and the key output (pageId consumed by other web_* tools). It also distinguishes itself from webpage_* tools, so an agent can pick it correctly among many 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?
Explicitly directs agents to use webpage_* tools when driving a browser on a real device, including the udid requirement. It also positions web_navigate as the entry point for the web_* family by noting that every other web_* tool takes the returned pageId.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
