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

Annotations only declare the safety profile (destructive, non-idempotent). The description adds rich behavior: the first call returns an approval preview, approved execution is atomic, omitted settings are unchanged, null clears a platform, and it never activates/enrolls/sends. This is significantly beyond what annotations provide.

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?

Front-loaded with the action, then logistics. Every sentence carries distinct, necessary information (scope, prerequisite, preview/approval flow, mutation semantics) with no redundancy.

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?

There is no output schema, but the description compensates by explaining the first-call preview return and the atomic save on approval, and by covering mutation semantics and the confirmation_token flow. Minor gaps remain around the exact preview contents, but this is complete enough for correct invocation.

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 baseline is 3. The description adds genuine semantic value beyond the schema by clarifying the omit-vs-null distinction ('Omitted settings remain unchanged'; 'Explicit null sender clears one platform') and the expected_updated_at provenance.

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 ('Change') and resource ('a campaign's manual review, send window, or sender assignments') and precisely scopes what it does NOT do ('never activates, enrolls, or sends'), which cleanly separates it from enable_campaign, pause_campaign, and update_campaign_workflow.

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?

Gives clear workflow context: read get_campaign first and copy its updated_at, and explains the two-step preview-then-approve flow. It does not explicitly name an alternative sibling to prefer or avoid (e.g. update_campaign_workflow), leaving some routing to inference.

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