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

Annotations only provide a title, so the description carries the full behavioral burden. It discloses the sequence of events (press, interpolated moves, release), the timing parameters, and the specific widgets it affects. It does not mention whether it blocks or returns after sending events, but for a drag operation this is a reasonable level of disclosure.

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?

A single, well-structured sentence that front-loads the main action and then explains the mechanism. Every clause adds value; there is no redundancy or 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?

For a 5-parameter tool with no output schema, the description covers the behavior, timing, and target types adequately. It does not explain return values (likely none) or session prerequisites, but these are implicitly covered by the schema and the tool's nature. It is complete enough for an agent to call it correctly.

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 all parameters are already documented in the input schema with descriptions. The tool description essentially restates the flow (press at from, steps interpolated, release at to) but adds no new semantic meaning beyond the schema. The baseline of 3 applies since the schema handles the heavy lifting.

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 a specific action (drag the mouse) with the resource (viewport positions) and details the mechanism (press, interpolated moves, release). It also distinguishes the tool by noting it moves AMarker-style drag targets and canvas selections, separating it from generic click tools.

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 usage for dragging operations that require mouse movement tracking, but it does not explicitly mention when to avoid it or name alternatives. It gives clear context about the type of targets it works on, which helps an agent decide, though not explicitly.

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