browser-mcp

browser_wait_for_element

Wait for a matching selector to appear, with optional visibility check, to ensure the element is ready before proceeding.

Instructions

Wait for an element matching selector to appear. Set visible=True to also require it to be rendered.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "selector": "<selector>"
    },
    "name": "browser_wait_for_element"
  }
}

Input Schema

Name	Required	Description	Default
`timeout`	No
`visible`	No
`selector`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 18, 2026

TDQS

B3.2/5.0

Behavior2/5

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

No annotations are provided, so the description must carry behavioral disclosure. It explains the visible toggle but omits what happens on timeout, whether it polls or uses events, and what a successful/failed wait returns or raises.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two clean sentences with no filler. The core behavior is front-loaded and the visible nuance is added in the second sentence.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a wait tool with no annotations and no output schema, the missing timeout outcome and return/error contract are significant. An agent cannot predict what happens if the element never appears, so the definition is not fully complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema description coverage, the description adds meaning for selector and visible, explaining that visible requires rendering. It leaves timeout with only a default value and no unit or behavior, so compensation for the schema gap is partial.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action: wait for an element matching a selector to appear, with an optional visibility requirement. It is clear about the resource, but does not explicitly contrast with sibling browser_wait or browser_wait_for_load.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The described behavior implies when to use it: when an agent needs to block until an element exists (and optionally is visible). However, it gives no explicit guidance on choosing this over browser_wait or browser_wait_for_load, and no conditions or exclusions.

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