browser_open

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action but does not mention potential side effects (e.g., opening a new window, resource usage), permissions required, or error conditions (e.g., invalid URL handling). For a tool that launches an external application with no annotation coverage, 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.

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

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded and every part of the sentence contributes to understanding the tool's function.

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

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

Given the tool's moderate complexity (launching a browser with two parameters) and no annotations or output schema, the description is minimally adequate. It covers the basic action but lacks details on behavior, errors, or integration with sibling tools, leaving gaps for an AI agent to infer usage correctly.

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

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

Schema description coverage is 100%, with both parameters (url and headless) fully documented in the schema. The description does not add any additional meaning beyond what the schema provides, such as explaining URL validation or headless mode implications. Baseline 3 is appropriate when the schema does the heavy lifting.

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

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

The description clearly states the specific action ('Launch Chromium browser and navigate to a URL'), including the resource (Chromium browser) and the operation (launch and navigate). It distinguishes itself from siblings like browser_navigate (which navigates an already open browser) and desktop_app_launch (which launches other desktop applications).

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

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

The description implies usage for opening a new browser instance, which differentiates it from browser_navigate (for existing browsers) and desktop_app_launch (for non-browser apps). However, it lacks explicit guidance on when to use this versus alternatives like browser_navigate or when not to use it (e.g., if a browser is already open).

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