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Glama

browser_close

Destructive

Close a specific browser instance and release its resources, without affecting other open browsers. Preserves identity so reopening returns to the same session.

Instructions

Close one browser and free what it was holding.

The page it had is gone with it. The other browser is not touched.

Who it was is kept: browser_open with no arguments brings the same person back. To be somebody else, pass a seed, a proxy or a profile.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
browserNoDefaults to `main`; `support` is the helper beside it.

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed1 schema field changedv0.68.0
    • addedInput schema / properties / browser / description
      Added value: +"Defaults to `main`; `support` is the helper beside it."
  2. First observedv0.43.0

TDQS

A4.5/5.0
Behavior5/5

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

Beyond the destructiveHint annotation, the description discloses important behavioral traits: the page is gone after closing, the other browser is not touched, and the browser's identity is preserved across close and reopen. This adds meaningful context about side effects and state persistence.

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?

The description is concise and well-structured: the primary action comes first, followed by immediate side effects, then the useful identity-persistence behavior. Every sentence contributes meaningful information without unnecessary length.

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

Completeness5/5

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

For a tool with one optional parameter, a clear output schema, and destructive annotations, the description covers all important behavioral aspects: what is freed, what is destroyed, what remains untouched, and how to reopen with the same or a different identity. Nothing essential is missing.

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?

The input schema already fully documents the only parameter, including its default value and the main/support distinction. The description adds no additional parameter-level detail, so the schema-description coverage baseline of 3 is appropriate.

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?

The description clearly states the action: 'Close one browser and free what it was holding.' It is specific about the resource affected and distinguishes itself from sibling tools by emphasizing that only one browser is closed and the other remains untouched.

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?

The description gives clear context about when to use the tool: to close a browser and free resources. It also clarifies the non-obvious follow-up behavior by explaining that browser_open with no arguments restores the same browser identity, and that passing a seed, proxy, or profile is needed for a different identity. It does not explicitly state exclusions, but the context is strong.

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