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Glama

browser_tab_new

Open a new tab in a controlled Chromium browser, optionally load a URL and switch to the new tab.

Instructions

Open a new tab and optionally switch to it.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
urlNoabout:blank
switchNo
session_idYes
wait_secondsNo

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.5.1

TDQS

C2.7/5.0
Behavior2/5

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

With no annotations, the description carries the full burden but discloses almost nothing: it doesn't say whether existing tabs are preserved, whether the session must be active, what happens if url is omitted (schema default about:blank), or how wait_seconds affects the call. For a state-mutating tab-creation tool this is a significant gap.

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

Conciseness4/5

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

A single short sentence with no filler, front-loaded with the main action. It is concise, but that brevity is partly the result of under-specification rather than tight editing.

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?

An output schema exists, so return values need not be described, but everything else is missing: parameter meanings, interaction with sibling tab tools, and side effects. For a 4-parameter tool with zero schema coverage and no annotations, the definition is too thin.

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

Parameters2/5

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

Schema description coverage is 0% across 4 parameters, so the description must compensate. It only gestures at 'switch' behavior; url, wait_seconds, and the required session_id are entirely unexplained, leaving the agent to infer semantics from bare titles.

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?

States a specific verb and resource ('Open a new tab'), so the agent knows exactly what happens. However, it does not distinguish itself from the sibling browser_tab_switch, which overlaps with the 'switch to it' behavior mentioned here.

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

Usage Guidelines2/5

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

No guidance on when to open a new tab versus reusing or switching tabs, and no mention of the browser_tab_switch/browser_tab_list siblings. The only hint is the word 'optionally', which is not actionable guidance.

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