Skip to main content
Glama
yogesh-joshi-0333

browser-control-mcp-server

by yogesh-joshi-0333
OverviewSchemaSourceRelated ServersDiscussionsAdmin
TypeScript
Local

Browser Emulate

browser_emulate

Emulate device and environment conditions on the current page by applying presets for viewport, color scheme, motion, timezone, locale, geolocation, permissions, network, and CPU throttling.

Instructions

Emulate device/environment conditions on the current page — device presets, dark mode, reduced motion, timezone, locale, geolocation, permissions, network throttling, and CPU throttling. Pass only the options you need; each is applied independently and the response lists what was actually changed. Geolocation and permissions are scoped to the page's current origin, so navigate first.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
modeNoForce a specific mode. Defaults to extension.
deviceNoA known device name, e.g. "iPhone 15 Pro", "Pixel 7", "iPad Mini". Sets viewport, user agent, and touch support together.
localeNoLocale/language, e.g. "fr-FR" — sent as the Accept-Language header (approximation; does not change navigator.language)
timezoneNoIANA timezone id, e.g. "America/New_York", "Asia/Kolkata"
sessionIdNoPuppeteer session ID for headless mode. Skips mode selection.
colorSchemeNoEmulate prefers-color-scheme
cpuThrottleNoCPU slowdown factor (e.g. 4 = 4x slower). Pass 1 to clear.
geolocationNoCoordinates to report for navigator.geolocation. Automatically grants the geolocation permission for the current origin.
permissionsNoPermissions to grant for the current origin, e.g. ["notifications", "midi"]. For clipboard-read/clipboard-write specifically, use browser_clipboard instead — this generic path does not reliably grant clipboard permissions in headless Chrome.
reducedMotionNoEmulate prefers-reduced-motion
networkThrottleNoNamed network condition preset, "offline" to disable the network, or "none" to clear throttling

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv1.5.0

TDQS

A4.2/5.0
Behavior4/5

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

With no annotations, the description carries the full burden and does disclose meaningful traits: independent per-option application, a response that reports what actually changed, and origin-scoped geolocation/permissions. It omits persistence/reset semantics (whether emulation survives navigation or how to clear it) and any mode-selection interaction, which are the main remaining behavioral gaps.

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 tightly written sentences that front-load the capability list, then the operating rule, then the one prerequisite. No filler and no repetition of the schema.

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

Completeness4/5

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

For an 11-parameter tool with no output schema, the description compensates by stating the response lists what changed and by flagging the origin-scoping prerequisite. Persistence across navigation and reset behavior are the only notable omissions.

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?

Schema description coverage is 100% and all 11 parameters are documented inline, so the schema already does the heavy lifting. The description's enumeration mirrors the schema rather than adding syntax, defaults, or interaction rules beyond it.

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

Purpose5/5

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

Specific verb (emulate) plus resource (device/environment conditions on the current page) with an explicit enumeration of the condition categories covered. No sibling tool in the list does emulation, so an agent can route to it unambiguously.

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

Usage Guidelines4/5

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

States that only needed options should be passed, that each is applied independently, and gives a real prerequisite ("navigate first" for origin-scoped geolocation/permissions). It stops short of naming alternatives or when-not-to-use cases in the description itself (the browser_clipboard carve-out lives in the schema).

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

Deploy Server

Other Tools