page_scroll

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

With no annotations provided, the description carries the full burden. It discloses that the tool reports the network/console/url delta caused by the scroll and mentions a settle time (waitMs) before reporting. This goes beyond a simple action description, though it does not cover edge cases like scroll-triggered navigation or iframe behavior.

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 two concise sentences, front-loaded with the core action. It efficiently conveys the two modes, default values, and the reporting behavior without any redundant phrasing.

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 description covers the main functionality but omits details such as what happens if both ref and selector are provided (precedence) or if neither is given. It also does not mention potential interactions with page state or nested elements. Given the tool has 5 parameters and no output schema, these gaps leave some ambiguity for edge cases.

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 40% (dy and waitMs have descriptions; ref, selector, sessionId do not). The description adds meaning by explaining that ref/selector trigger element scrolling and dy is the vertical pixel amount, and it clarifies the default for dy and waitMs. It does not explain sessionId, but that appears to be a common context parameter across sibling tools.

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 ('Scroll the page') and specifies two distinct modes: scrolling an element into view via ref/selector, or scrolling the window by dy pixels. This distinguishes it from sibling tools like page_goto (navigation) and page_find (search) without ambiguity.

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 provides clear context on when to use each mode (element scroll vs window scroll) but does not explicitly mention alternatives or when-not-to-use scenarios. Since it is likely the only scroll tool among siblings, the implicit usage is clear, but it lacks explicit exclusion guidance.

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