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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the concrete guarantee 'without sending or changing records' and notes the 'authorized' single-campaign scope, which is useful but does not add return format or pagination behavior.

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?

The description is a single sentence that front-loads the action and resource, then adds a meaningful safety qualifier. There is no filler or 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?

For a simple read-only two-parameter preview tool, the description combined with schema and annotations is nearly complete. The only notable gap is the absence of what the preview return value looks like, but no output schema is declared and the meaning is largely inferable.

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%, so both parameters are already documented well: limit has min/max/default, and campaign_id notes it comes from search-reactivation-campaigns. The description's phrase 'one authorized reactivation campaign' reaffirms campaign_id but does not add substantive meaning beyond the schema.

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 uses a specific verb ('Previews') and a specific resource ('dormant customers eligible for one authorized reactivation campaign'). It also explicitly distinguishes itself from sending or changing records, which differentiates it from campaign-sending siblings and other preview tools.

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?

The description implies when to use the tool: to safely see which dormant customers are eligible for one reactivation campaign. However, it does not explicitly state when not to use it, nor does it point to search-reactivation-campaigns as the way to obtain campaign_id beyond what the schema already says.

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