Take browser session screenshot

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description still adds real behavior: no navigation occurs, element capture waits and scrolls into view, and the return includes the image plus the current URL. It omits cost/size implications and timeout behavior, keeping it below a 5.

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 tight sentences, front-loaded with the core action and the 'no navigation' constraint, then the alternative tool. Nothing is redundant, though the second sentence's phrasing is slightly clipped.

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?

No output schema exists, and the description compensates by stating what is returned (the image and current URL). Combined with annotations and full schema coverage, an agent has enough to call it correctly; missing pieces like full_page behavior and timeout effects are minor and schema-documented.

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% and each parameter (ref, selector, full_page, quality, image_type, timeout) is documented in-schema, so the baseline of 3 applies. The description's only additional signal is that capture targets either the page or 'one element', which is already inferable from the schema.

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 ('Capture the current page or one element') and adds the key constraint 'without navigating', which separates it from navigation-capable siblings like browser_open/browser_fetch. It does not explicitly contrast with browser_extract or browser_evaluate, so sibling differentiation is partial.

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?

One usage pointer is given ('Use browser_actions for other waits before capture'), which is genuinely useful. However there is no guidance on when to prefer screenshots over browser_extract/browser_evaluate, nor on when not to use it (e.g. session not yet fetched, non-visual data extraction).

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