Create a campaign on an ad account (created paused unless status is given)

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

Annotations only declare readOnlyHint=false and openWorldHint=true; the description adds the crucial behavior that calls are simulated unless confirm is true, and that campaigns land in paused state unless status is supplied. What it does not cover is permission requirements, validation failure behavior, or what the dry-run preview returns.

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 with the safety-critical dry-run rule placed prominently at the end. The opening sentence largely duplicates the tool title, which is minor redundancy but does no harm.

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 mutation tool with no output schema, the description covers the two things an agent could get wrong: accidental execution (dry run by default) and unexpected entity state (created paused). The remaining details are carried by a rich, mostly documented input schema.

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 67%, and the description only elaborates on two things the schema already documents: the status default and confirm/idempotency semantics. The nested body fields (bid, budget, platformNative, destinationUrl) get no explanation in the description beyond inline schema text.

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?

Names a specific verb and resource (create a campaign on an ad account) and states the endpoint POST /v1/campaigns. The default-paused clause narrows behavior usefully, but the description never distinguishes this from siblings such as campaigns_update or campaigns_setStatus.

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 dry-run-by-default rule plus 'set confirm: true to execute' is genuinely actionable guidance on how to invoke it safely. However, there is no stated when-to-use versus alternatives (e.g., campaigns_update for existing campaigns, crosspost_launch for multi-platform deployment), so routing between siblings is left to inference.

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