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

Annotations already flag destructive=true and openWorldHint=true, but the description adds crucial context: recipients start receiving the campaign immediately, the user should be confirmed first, and schedule-level sending limits and pauses still apply. This materially helps an agent understand consequences beyond structured 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?

The description is three short sentences, front-loads the action, then immediately states the critical warning and confirmation requirement. No sentence is wasted.

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 destructive external-send action with rich annotations, complete parameter schema, and no output schema, the description covers the essential context: what it does, the immediate sending consequence, confirmation guidance, and inherited scheduling limits.

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 100%, so both campaignId and apiKey are already documented in the schema. The description adds no campaignId syntax, format, or apiKey override behavior, which is acceptable given 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 states a specific verb and resource: resume a paused campaign. It is immediately distinguishable from siblings such as pause_campaign and schedule_campaign because it names the paused-state precondition.

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?

It gives a clear usage condition—resume a paused campaign—and adds a confirmation requirement before invocation. It references schedule_campaign for sending limits and pauses, but does not explicitly state when to avoid this tool in favor of scheduling or other campaign actions.

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