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

The description adds behavioral context beyond the destructive and idempotent annotations by explaining the limitation that you cannot add an exclusion (which names the caller's own browser) and the permission requirement. This reveals constraints and side effects that are not fully captured by the annotations alone.

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 concise, consisting of just a few sentences that cover purpose, limitations, and permissions without any fluff or repetition. Each sentence adds valuable information, and the structure is logical and easy to scan.

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?

Given the tool's simplicity and the presence of an output schema, the description provides all necessary context: what the tool does, when to use it, its constraints, and its permission requirements. Nothing essential is missing for an agent to correctly invoke it.

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?

Both parameters are described with meaningful, user-oriented explanations. The label is defined as the human-given device label, and siteId is explained with its conditional necessity. These descriptions go beyond mere type info and clarify the intended use, which justifies a score above the baseline for full schema coverage.

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 tool's purpose: to remove an exclusion and put a device back into measurement. It also provides helpful context about what exclusions are and explicitly contrasts with adding an exclusion, making the purpose unambiguous.

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 gives practical usage guidance by stating that adding an exclusion is not possible with this tool and by mentioning the required measurement permission. It does not explicitly enumerate alternative sibling tools, but the contrast with ADD and the permission note serve as clear usage instructions.

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