selection_set

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

With no annotations, the description carries the full burden but only discloses the geometry-handling difference between actions. It says nothing about side effects on prior selections, session/auth requirements, or reversibility of a state mutation.

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 purpose and followed by the one non-obvious conditional. 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?

An output schema exists, so return values need not be described. However, with six parameters at 0% coverage and no annotations, the omission of enum semantics and session context leaves the definition short of what an agent needs to call it reliably.

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 0%, so the description must compensate. It usefully explains that x/y/width/height are pixel coordinates and dimensions only relevant to the rectangle action, but it leaves the action enum values and the session_id parameter entirely unexplained.

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 ('Set the current selection') and goes further by explaining that only the rectangle action consumes geometry while others ignore it. There are no sibling selection tools to differentiate against, so this is a clear, self-contained purpose.

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 never says when to use this tool, when not to, or how the four enum actions (none/all/invert/rectangle) should be chosen. It only clarifies geometry relevance for rectangle, which is parameter behavior rather than usage guidance.

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