browser_navigate

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

Annotations already declare destructiveHint=false and openWorldHint=true, so the safety profile is partly covered. The description adds genuine behavioral context beyond them: it creates a session, returns a session_id consumed by all other browser_* tools, and crucially that the session holds one concurrency slot until browser_close releases it.

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?

Front-loads the core action, then lifecycle detail, then option guidance in a scannable list. Every sentence contributes, though the 'backed by Zenrows' hosted browser infrastructure' phrasing is mildly decorative.

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?

For a three-parameter tool with no output schema, it covers purpose, session lifecycle, the returned session_id, the concurrency constraint, and when to use each option. Failure/error behavior on a bad URL or unreachable site is the only notable omission.

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 coverage is 100%, so both proxy parameters are already fully documented in the schema (formats and examples included). The description adds the 'when to use' rationale for each option, which is useful but shallow, so baseline 3 is appropriate.

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?

States a specific verb and resource ('Open a ... session and navigate to a URL') and explicitly frames itself as 'the entry point for all browser automation'. It distinguishes itself from the many browser_* siblings by declaring it creates the session_id that every other browser_* tool requires.

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?

Provides the entry-point context and an explicit 'When to use options' block mapping proxy_country to geo-restricted content and proxy_region to geo-targeted proxies. It does not, however, state when to use this versus non-browser siblings like scrape or extract, so it stops short of naming exclusions.

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