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

Annotations already provide idempotentHint, destructiveHint, readOnlyHint. The description adds nuanced behavior: pausing is temporary, can be reactivated, and returns an updated media buy object. No contradiction with annotations.

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?

Four short labeled sections, each with a single focused sentence. No filler; every sentence adds information.

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 simple state-change tool with two parameters and no output schema, the description covers purpose, usage constraints, lifecycle (temporary vs permanent), and output format. Complete.

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 have descriptive schema text (100% coverage), so the description need not repeat them. It does not add extra parameter-level detail, but the baseline of 3 applies due to high 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 uses a specific verb ('Pause') and resource ('media buy campaign'), and explicitly contrasts with 'activate' and 'cancel' in combination hints, clearly distinguishing it from sibling 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 'when_to_use' section explicitly states the use case (temporarily stop a running campaign) and the constraint (only works on active campaigns). It also names alternatives (activate, cancel) and their permanence.

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