create_campaign_hierarchy

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

With no annotations provided, the description carries the full disclosure burden and meets it: it reveals the non-atomic partial-failure behavior ('If any step fails, earlier objects remain'), the return shape (all three IDs), and that cleanup requires separate update/archive calls. This is precisely the kind of operational surprise an agent needs to know before invoking.

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?

Five short sentences, each carrying distinct information: purpose, use case, return value, failure semantics, and alternative routing. There is no filler, no restatement of schema fields, and the most decision-relevant facts are front-loaded.

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 mutating composite tool with no output schema and no annotations, the description covers the critical operational facts: single-call creation, three returned IDs, and partial-failure cleanup. The minor gap is that it does not clarify the role or necessity of ad_account_id, which the schema also leaves undocumented.

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 80%, with the schema already documenting the campaign/ad_group/ad payloads and the idempotency_key suffixing behavior, so the baseline applies. The description adds no parameter-level detail and does not compensate for the one undocumented parameter (ad_account_id).

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: 'create a full campaign -> ad group -> ad chain in one call.' It clearly identifies this as a composite workflow, which distinguishes it from the atomic create_campaign, create_ad_group, and create_ad siblings without needing to inspect their 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?

Explicitly states when to use it ('Useful for quick end-to-end creation') and when not to, naming the alternatives ('Prefer atomic tools (create_campaign, create_ad_group, create_ad) for fine-grained control'). It also routes post-failure cleanup to update/archive tools, leaving little to inference.

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