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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: the result is an *unpaid* campaign, creative lineage is preserved, prices are re-fetched, and a fresh review plus payment are required. That payment/review requirement is exactly the kind of extra context annotations cannot express.

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 tight sentences with no filler, and the core operation (copy into a new unpaid campaign) is front-loaded before the lineage/price and review/payment consequences. Every clause earns its place.

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 output schema exists, so return values need no explanation, and annotations cover safety and idempotency. The description supplies the key operational consequences (new unpaid campaign, fresh pricing, required review and payment). The only gap is eligibility — which prior campaigns can be rebooked and what happens to the original — leaving it just short of complete.

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 100% with all four parameters documented, including the idempotency key retry semantics and the YYYY-MM-DD date pattern, so the baseline is 3. The description's 'for new dates' loosely maps to flightStart/flightEnd and 'previous campaign' to advertisementId, but it adds no format, constraint, or validation detail beyond what the schema already provides.

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 gives a precise verb and resource: copy a previous campaign into a new unpaid campaign for new dates. The phrase 'copy a previous campaign' is specific enough to distinguish it from siblings like save_campaign_draft or prepare_campaign_booking, but it never names or contrasts those siblings explicitly, which is the only thing separating this from a 5.

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?

'Rebooking requires a new review and payment' signals a prerequisite, which is useful context for deciding whether to proceed. However, there is no explicit when-to-use vs when-not guidance, no statement of what campaign states are eligible for rebooking, and no routing to alternatives such as prepare_campaign_booking or save_campaign_draft.

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