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Glama

list_tabs

Retrieve all open browser tabs in the shared browser session, including ID, URL, title, loading status, and active state, to inspect what the human sees.

Instructions

List all open browser tabs (id, url, title, loading, active). The human sees the same tabs.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.2.1

TDQS

A4/5.0
Behavior3/5

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

With no annotations provided, the description carries the full burden. It does disclose that it returns all tabs unfiltered and that the human sees the same set (useful context), but it says nothing about ordering, permissions, or how the operation behaves. Adequate but incomplete for a tool with zero annotation coverage.

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 short sentences with zero waste. The purpose is front-loaded and the field list follows immediately.

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?

There is no output schema, so the description's enumeration of returned fields (id, url, title, loading, active) is genuinely load-bearing and covers the return contract. For a parameterless read tool the only remaining gap is ordering/behavioral detail.

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

Parameters4/5

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

The tool takes no parameters, so the baseline is 4. The description's field list arguably describes the (absent) input, but there is nothing to misinterpret.

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 names a specific verb+resource ('List all open browser tabs') and enumerates the returned fields (id, url, title, loading, active), which lets an agent distinguish it from siblings like new_tab, close_tab, and switch_tab without opening any schema.

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?

Usage is only implied by the verb 'List' and the fact that it returns all tabs; there is no explicit when-to-use guidance, no mention of the obvious alternatives (switch_tab, close_tab), and no exclusions. An agent can infer purpose but gets no routing help.

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