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

With NO annotations provided, the description carries the full burden and delivers richly: it discloses that activation 'STARTS REAL AD SPEND', that agents cannot activate and a human must approve, that pausing stops spend, and includes a full outbound-tier rail explaining per-call manager approval, one-time send, and no standing grant. This is exemplary disclosure for a financial mutation tool.

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 essential risk information (spend, human-only activation) is front-loaded, and every sentence carries substance—there is no filler. The outbound-tier block is long but each clause (per-send rail, queues approval card, sends once, no standing grant) is load-bearing, so the density is justified rather than wasteful.

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 annotations and no output schema, the description covers purpose, spend risk, human approval flow, when-to-use, and sibling differentiation comprehensively. The only minor gap is the unspecified return format/confirmation shape after the approval is queued, which is non-critical for a state-change tool.

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 100%, so the baseline is 3. The description conceptually references the status values (ACTIVE/PAUSED with spend semantics) but adds little beyond what the schema already documents for parameters like object_type, object_id, and ad_account_id. The schema does the heavy lifting.

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-resource pair ('Activate or pause an X campaign or line item') and explicitly differentiates from the sibling 'set_meta_ad_status'. The platform and target object are unambiguous, so an agent can distinguish this tool from near-names without opening schemas.

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 names the sibling alternative (set_meta_ad_status) and gives explicit trigger conditions: 'Use after the user has reviewed a paused X draft and explicitly says to launch, or asks to stop a running X ad.' Both when-to-use and the Meta/X routing distinction are stated.

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