Open a URL in a browser session

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

Beyond annotations, the description discloses that the tool waits for the page to settle, reports the final URL and changes, and that the snapshot is off by default because it is expensive. These are meaningful behavioral details. It does not contradict the openWorldHint or destructiveHint annotations.

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?

Two concise sentences front-load the core behavior and then add the key option. Every clause earns its place with no repetition of schema details.

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 navigation tool with no output schema, the description covers the main behavioral contract: navigating, waiting, reporting URL and changes, and the snapshot option. It does not fully describe the shape of the returned changes, but with annotations covering safety and 100% parameter schema coverage, the gaps are acceptable.

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 the baseline is 3. The description adds value by explaining include_snapshot ('also read the page', 'expensive') and by clarifying what navigation returns ('reports the final URL and changes'), which gives context to the url and session_id parameters.

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: 'Navigate a live session and wait for it to settle.' The title 'Open a URL in a browser session' reinforces the resource and action. It does not explicitly compare against sibling tools like steel_scrape or steel_act, so it misses full differentiation.

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 when to use it: to navigate a live session and wait for it to settle, with include_snapshot when page content is needed. However, it offers no explicit exclusions or alternatives among siblings, such as 'use steel_scrape for extraction' or 'use steel_act for actions.'

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