browser_mouse_click

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden, and it delivers meaningful mechanism detail: it dispatches Input.dispatchMouseEvent through the browser's input pipeline and produces isTrusted events (material for anti-bot behavior), versus JS el.click(). It stops short of covering failure modes, whether the target must be in view, or timing behavior, which keeps it off a 5.

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, front-loaded with what the tool is, then the contrast with the sibling, then the usage trigger. No sentence is redundant and nothing is buried.

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. Purpose, alternative, and usage are complete; the only gap is the undocumented button/wait_seconds parameters, which is minor for a click tool.

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% across 5 parameters, so the description must compensate. It adds real meaning for x/y ('viewport pixel position'), but says nothing about button (default left) or wait_seconds (default 1.2), leaving two parameters undocumented in both places.

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+resource ('coordinate click at viewport pixel position (x, y)') and immediately distinguishes itself from the sibling browser_click by mechanism. An agent can tell the two apart without opening either schema.

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 names the alternative (browser_click) and the condition selecting this one: 'Use when you need to click by coordinates — e.g. inside iframes or at positions obtained from screenshots/evaluation.' Both when and the concrete scenarios are given.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.