browser_state

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states it returns a JSON envelope with browser state, which is transparent about the output. However, it doesn't mention whether the operation is read-only (though 'Get' implies it), any side effects, or potential error conditions like an unopened browser. The description is adequate for a simple read but lacks explicit safety or prerequisite context.

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 extremely concise: two short paragraphs, front-loaded with the core purpose, then args and returns. Every sentence adds value with no redundancy. The structure is clean and easy to parse.

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?

The tool has an output schema (as indicated by context), so the description doesn't need to detail return values beyond mentioning the JSON envelope. It covers the single parameter and its source. It's complete for a simple read-only operation, though it could explicitly mention if the browser must be open, but that's implied by 'browser state' and 'from list_devices'.

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?

The schema has zero description coverage for the parameter, but the description compensates by explaining 'serialno: The browser device serialno, from list_devices.' This adds meaning beyond the raw schema, telling the agent where to obtain the value and its purpose. For a single-parameter tool, this is fully sufficient.

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 action (Get) and the specific resource: current URL, title, viewport, and tab count. This distinguishes it from navigation or manipulation tools like browser_navigate or browser_tabs, which focus on changes or tab-specific actions. It's unambiguous and actionable.

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 reading browser state but doesn't explicitly state when to use it vs. alternatives. It mentions 'from list_devices' for the parameter, which hints at a prerequisite, but there's no explicit guidance on when to prefer this over other browser inspection tools like browser_tabs or browser_text. Usage context is inferred rather than stated.

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