Browser Hover

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the mechanics ('mouse moves to the element center and stays there'), which tells the agent the hover is positional and persistent rather than a synthetic event. It does not disclose failure behavior when the selector matches nothing, whether it waits for the element, or whether hover state persists across subsequent calls.

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 short sentences, front-loaded with the action, then the mechanics, then the routing guidance. No filler and nothing that restates the tool name or title.

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 three-parameter, no-output-schema, no-annotation tool, the description covers purpose, usage routing, and core mechanics adequately. Remaining gaps are edge behaviors (missing element, timing, persistence of hover state) rather than anything required to invoke it correctly.

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% and every parameter (mode, selector, sessionId) already has its own description in the schema. The description adds no parameter-level detail beyond that, so the baseline 3 applies.

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 (hover) on a specific resource (an element) and enumerates the concrete outcomes it produces: dropdown menus, tooltips, hover effects, mouseover-activated content. It also distinguishes itself from the closely related browser_click by naming that sibling.

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?

Gives an explicit usage condition and sequencing rule: 'Use this before browser_click when a menu only appears on hover, or to reveal hidden UI elements.' That covers when to use it and the alternative it pairs with, but offers no when-not guidance (e.g., for elements that respond to click directly).

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