browser_click_at

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

With no annotations, the description carries the full burden. It discloses that it uses 'real CDP mouse events' and 'pierces through iframes and ad overlays', but does not detail other behavioral aspects like mouse movement, scroll triggering, or behavior when coordinates are outside the viewport.

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 concise with only two sentences. The first sentence states the core action and method, and the second provides a key differentiator. No unnecessary words.

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 simple coordinate-click tool with no output schema, the description is mostly complete. It covers the action and a key use-case. However, it could improve by mentioning the coordinate origin (e.g., viewport vs page) and any post-click behavior (e.g., waiting for page load).

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%, with each parameter described in the schema. The description adds no additional meaning beyond what the schema provides for x and y, so a baseline score of 3 is 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?

The description clearly states it clicks at absolute (x,y) coordinates using CDP mouse events, and distinguishes itself from sibling `browser_click` by noting it pierces through iframes and ad overlays that block CSS-selector clicks. This tells the agent exactly what the tool does and how it differs.

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 description implies usage when CSS-selector clicks fail due to overlays, providing clear context. However, it does not explicitly state when not to use it or mention alternatives like `browser_click` for normal clicks, nor does it specify any prerequisites for obtaining coordinates.

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