browser_screenshot

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

With no annotations, the description carries the full burden and does disclose two non-obvious traits: the return value ('Returns the saved file path') and that the capture targets the active tab of the focused window rather than a specified tab. Still missing are failure modes (no page loaded, file naming/location, format, whether it blocks), but the core behavioral picture is present.

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 short sentences plus one caveat, front-loaded with the action and its return value, then the tab-scoping note. Every sentence earns its place; nothing is padded.

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 zero-parameter, no-annotation tool with no output schema, the description covers what the tool does, what it returns, and the tab-focus constraint. The remaining gap is disambiguation from browser_full_page_screenshot and browser_element_screenshot, which the sibling set makes a realistic source of wrong-tool selection.

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 tool takes zero parameters, so per the calibration baseline this is a 4. The description correctly implies there is nothing to configure — capture is scoped implicitly to the active tab — and adds no misleading parameter-like language.

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 a screenshot of the current page.' An agent immediately knows the operation. It does not, however, distinguish itself from the closely named siblings browser_full_page_screenshot and browser_element_screenshot, leaving the viewport-vs-full-page boundary to inference.

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?

Gives an explicit precondition — switch to the target tab with browser_switch_tab first — which is real routing guidance to a sibling. It stops short of saying when to prefer this over browser_full_page_screenshot or browser_element_screenshot, which are the most likely alternatives for the same intent.

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