Update a campaign (name, budget, schedule, status, platformNative)

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

Goes well beyond the annotations: annotations only say readOnlyHint=false and openWorldHint=true, while the description discloses the critical safety behavior that the call is a dry run by default and only executes when confirm: true is set. It does not say whether the body is a partial merge or full replacement, or what the dry-run preview contains, which keeps it from a 5.

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 zero waste: purpose and target fields first, then the write/safety constraint. The most consequential detail (dry run by default) is stated plainly and last, which still reads cleanly.

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 a nested body, no output schema, and two required parameters, the description covers the essentials: the endpoint, the writable surface, and the confirm gate. Remaining gaps are patch semantics (are omitted fields preserved?) and permission requirements, which matter for a destructive-capable write on an open-world API.

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 only 50%, so the description should compensate more than it does. It does enumerate the writable fields (name, budget, schedule, status, platformNative), which helps map intent to the nested body, but it uses 'schedule' where the schema has startAt/endAt and says nothing about the nested budget micros/currency shape or platformNative's free-form contents.

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 (Update), resource (campaign), the mutable field groups, and the underlying endpoint (PATCH /v1/campaigns/{id}). It does not distinguish itself from the sibling campaigns_setStatus, which also changes status, so an agent cannot tell from the description alone which of the two to pick for a status change.

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?

Usage is only implied by the verb 'update' – there is no statement of when to prefer this over campaigns_setStatus, campaigns_create, or campaigns_get. The dry-run/confirm sentence is operational guidance for invoking this tool, not guidance for selecting among alternatives.

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