browser_click_at

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

Annotations already flag destructiveHint=true and readOnlyHint=false, but the description adds critical behavior beyond that: it moves the pointer first (no teleport), does down/up, holds if hold_seconds is set, returns a screenshot, and crucially discloses that coordinates are viewport-relative and go stale, with no exception raised on staleness. This is exactly the kind of behavioral context an agent needs and is not provided by annotations.

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 structured with purpose first, then mechanics, then critical caveats, then alternative routing. Each sentence earns its place—no filler. The front-loaded purpose and explicit contrast with the sibling make it immediately scannable for an agent.

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 coordinate-click tool with no output schema, the description covers the essential context: how the click is performed, coordinate system, staleness risk, error behavior, and the recommended alternative. Nothing an agent needs to decide when and how to call it correctly is missing.

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 only 25% (only 'browser' has a description). The description compensates by clarifying x/y as raw viewport coordinates (relative to viewport, not page) and explains hold_seconds behavior. It doesn't specify units or allowed ranges, but it adds meaning beyond the bare schema, so a 4 is fair.

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 opens with a precise verb and resource: 'Click (or press-and-hold) a raw viewport coordinate instead of a selector' and immediately contrasts it with browser_click, its sibling. It names the exact use case (slider track, canvas-drawn captcha, precise point) and explicitly states it is an alternative to selector-based clicking, leaving no ambiguity.

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?

It gives explicit when-to-use ('for targets a selector cannot reliably reach'), when-not-to-use ('prefer browser_click with the element's `selector` whenever it has one'), and a practical condition (take a fresh snapshot after anything that could have moved the page). This fully routes the agent to the correct tool in context.

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