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

No annotations are supplied, so the description carries the full behavioral burden and does not meet it: it never states whether the duplicate is created paused (that fact lives only in the schema), whether source ads/keywords/budgets carry over, whether the call is idempotent, whether it requires write permission, or whether it returns the new campaign ID. Only one behavioural detail is offered, that ad placements default from the source supply sources.

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 short sentences with the action front-loaded and no filler. The second sentence is somewhat cryptic ('supplySources' is never defined) and the '(CM REST)' parenthetical is opaque, but there is no padding.

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?

An eight-parameter mutating tool with no annotations and no output schema needs more: what gets copied, whether the result is returned, and what happens on name collisions are all unstated. The description is far too thin for this complexity.

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 schema already documents all eight parameters including defaults like PAUSED and false. The description adds only 'adPlacements default from source supplySources', which largely restates the schema's '(default from source)' note and does not clarify the many string-typed booleans or the notification_message semantics. Baseline 3 applies.

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?

Clear specific verb+resource: 'Duplicate an existing campaign', with a platform hint '(CM REST)'. It is distinguishable from create_campaign, but the near-neighbour sibling reload_campaign_from_campaign is never acknowledged, leaving the agent to infer which of the two to use.

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?

No when-to-use guidance, no prerequisites, and no mention of alternatives such as create_campaign or reload_campaign_from_campaign. The agent must already know the campaign ID before it can pick this tool, and nothing in the text says so.

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