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

Annotations already declare idempotentHint=true and destructiveHint=true; the description's idempotency sentence largely restates the annotation, though the 'never makes the campaign active' clause is genuinely useful behavioral context the annotations cannot convey. The destructiveHint=true is never explained — an agent cannot tell why restoring is destructive (e.g., dropped unsent drafts or contacts) or what side effects the optional body fields trigger.

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 core action and the state outcome. The final idempotency sentence is largely redundant with the idempotentHint annotation, but overall there is little waste.

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?

No output schema exists, and the description does not cover the return shape, the two undocumented nested body parameters, or the concrete effect captured by destructiveHint. For a mutating restore tool with a nested request body, an agent has enough to know what it does but not enough to call it safely or correctly in every case.

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 0% and the description mentions no parameters at all — not the required campaign id, nor the optional nested body fields after_message_id and discard_unsent_drafts. For a tool with a nested optional object whose semantics are far from obvious, this leaves the agent guessing at what those fields do.

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 and resource ('Restores an archived or discarded campaign') and names the resulting states, so the agent knows exactly what object is affected. It does not distinguish itself from the closely related sibling restoreCampaignDrafts (which restores drafts inside a campaign), leaving that disambiguation to inference.

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?

Clearly scopes when to use it: only for archived or discarded campaigns, and adds that the restored campaign is never made active and a paused campaign must still be resumed to send. It stops short of naming alternatives (restoreCampaignDrafts, duplicateSequenceTemplate, createCampaign) or stating preconditions such as required permissions.

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