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

Annotations already declare readOnlyHint=true, destructiveHint=false and idempotentHint=true, so safety is covered; the description reinforces this with 'Writes nothing' and adds the preview-then-apply workflow context, which annotations cannot express. It does not mention failure modes or the 500-character input limit (that lives in the schema), so it is strong but not exhaustive.

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 tight sentences with no filler; the plain-English instruction and the 'Writes nothing' reassurance are front-loaded, and the follow-up call to apply_campaign_change comes last where it belongs.

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?

With no output schema, the description carries the return-value burden and does so ('get back exactly what would change'). Combined with the workflow instruction and the schema's parameter docs, an agent has everything needed to call it correctly and act on the result.

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 baseline is 3, but the description adds real meaning by giving four concrete example values ('only send on weekdays', 'cut it to 10 a day', etc.) that illustrate the expected plain-English input format for 'change'. It says nothing further about workspaceId, which the schema already routes via get_status.

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 ('Describe a change ... and get back exactly what would change') and immediately pins the scope with 'Writes nothing.' It also names the sibling apply_campaign_change as the counterpart, so the agent can distinguish preview from commit without opening a schema.

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 explicit sequencing: 'Show the result to the person, then call apply_campaign_change with the same changes to make it real.' That is both the when-to-use condition and the named alternative, with no inference required.

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