page_drag

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

With no annotations, the description carries the full behavioral burden. It discloses the exact event sequence (mousedown → move → mouseup), the coordinate system, the fact that no DOM target is required, and that it reports the resulting network/console/url delta, making side effects visible.

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 a single dense sentence where every clause earns its place: coordinate space, units, image-space equivalence, event sequence, no-DOM-target usage, and reported output. It is front-loaded with the action and contains no filler.

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 required parameters are semantically covered, the event behavior is explicit, and the reported delta is stated even without an output schema. The only notable gaps are the undocumented optional sessionId and the lack of detail about the exact shape of the reported delta.

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 description coverage is only 17%, but the description compensates for the four coordinate parameters by defining them as raw viewport CSS-px coordinates in screenshot space. waitMs is already described in the schema, while sessionId remains unexplained, preventing a 5.

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 uses a specific verb ('drag'), a precise resource (mouse at raw viewport coordinates), and a clear outcome (report network/console/url delta). It also distinguishes itself from coordinate-based siblings like page_click_at and page_tap_at by specifying mousedown→move→mouseup and no DOM target.

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?

It clearly implies when to use this tool: when a drag gesture is needed in the same coordinate space as page_screenshot/page_look images and no DOM element is targeted. It does not explicitly name alternative tools or state when not to use it, so it stops short of a 5.

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