Hovers an element identified by reference or CSS selector, then reports changes in network activity, console messages, and URL.
Hover an element (by ref from page_snapshot, or CSS selector) and report the network/console/url delta it caused.
| Name | Required | Description | Default |
|---|---|---|---|
| ref | No | ||
| waitMs | No | settle time after the hover before reporting the delta (default 700ms) | |
| selector | No | ||
| sessionId | No |
Changes observed during successful MCP inspections.
v0.6.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations present, the description carries the full burden of behavioral disclosure. It does reveal meaningful behavior: the hover triggers a network/console/url delta report and accepts either a ref or selector. Yet it does not clarify prerequisites such as element visibility, whether the hover is synthesized, what happens on failure, or how deltas are returned.
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?
A single sentence with no filler. The verb and target are front-loaded, and the parameter clarifications are packed compactly into the parenthetical. Every part of the sentence earns its place.
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 description conveys the core purpose and output dimensions, which is adequate for a relatively simple tool. However, with no output schema, no annotations, and only 25% schema description coverage, an agent is left guessing about how the delta is reported, whether a ref or selector is required, and what happens when multiple or no locators are provided.
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%, so the description must compensate. It adds meaning for ref and selector by explaining that ref comes from page_snapshot and selector is a CSS selector, but sessionId remains undocumented and the relationship/precedence between ref and selector is not addressed.
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 uses a specific verb ('Hover'), identifies the resource ('an element'), and specifies the two accepted input forms ('ref from page_snapshot, or CSS selector'). It also names the output ('network/console/url delta'), which clearly distinguishes it from siblings like page_click or page_find.
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 makes the core use case clear: hover an element and observe resulting deltas. However, it does not explicitly state when to choose this over sibling tools such as page_click or page_find, nor does it provide exclusion criteria or alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.