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

Annotations already declare this is a non-read-only but non-destructive, closed-world mutation. The description adds one genuinely useful behavioral fact beyond that: the result is a NEW DRAFT (not launched) campaign, and the original is untouched ('copy'). It does not say what is included in the copy (ads, keywords, targeting, extensions) or whether credits/publish state are affected.

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?

A single short sentence with zero filler, and the most decision-relevant fact (the output is a new draft) is placed at the end where it lands. Nothing needs trimming.

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 2-parameter tool with full schema coverage the description is adequate, and it correctly signals the resulting draft state. However, with no output schema, an agent would benefit from knowing what the call returns (e.g., the new campaign's id/name) and what content gets carried over, neither of which is covered.

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%, and the schema already explains campaign_id status restrictions and the name auto-generation pattern in detail. The description adds nothing parameter-specific; 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?

States a specific verb (duplicate/copy) and resource (campaign), plus the outcome state (a NEW DRAFT campaign), which distinguishes it from create_campaign. It never names a sibling explicitly, so an agent must infer that this is the copy path rather than the build-from-scratch path.

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?

There is no guidance on when to choose this over create_campaign, manage_campaign, or duplicate_negative_keywords_list, and no prerequisites are stated. The only hint is the 'new draft' outcome, which implies cloning as an alternative to building a campaign from scratch but does not say so.

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