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

The description adds a behavioral fact the annotations do not carry: copies are created PAUSED, which materially changes what an agent must do afterward. It also discloses that campaigns/ad sets bring their children along. It does not say what the tool returns (no output schema exists) or how name collisions are resolved beyond the schema's rename_suffix.

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?

Three short sentences, front-loaded with the action and resource, then the two facts an agent most needs (resulting PAUSED state, optional target placement). No filler or redundant restatement of the title.

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 openWorldHint and no output schema, the description covers the essentials: what gets copied, what state the copy lands in, and where it can be placed. It omits the return value (presumably new entity IDs) and whether the source must be in the same account, which an agent may need before chaining further calls.

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 71%, and the two required params (level, id_or_name) have no schema descriptions at all; the description partially compensates by mapping "campaign, ad set or ad" to the level enum and framing id_or_name as the source entity. It restates the 'into' semantics already in the schema and adds nothing about account/folder scoping or how id_or_name resolves ambiguity.

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?

"Copy a campaign, ad set or ad" names a specific verb and the three resource levels, which inherently separates it from the create_* siblings (meta_create_campaign, meta_create_adset, meta_create_ad) and from meta_rename. It also states the child-copying scope, but never names an adjacent tool explicitly, so it stops just short of full sibling differentiation.

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?

"Optionally into another campaign/ad set" conveys the cross-placement use case, so an agent can infer this is for reusing an existing structure rather than authoring a new one. There is no explicit when-not guidance (e.g. cross-account copying, or when to prefer building fresh with the create_* tools), leaving that to inference.

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