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 useful context ('without sending or changing records,' 'eligible completed jobs'), but it does not disclose additional behavioral details such as auth requirements, rate limits, or pagination behavior. There is no contradiction with annotations.

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?

A single, compact sentence communicates the tool's purpose, scope, and side-effect-free nature. It is front-loaded with the action and includes no filler or redundant restatement of the title/name.

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 two-parameter, read-only preview tool with full schema coverage, the description is largely sufficient. The only minor gap is that there is no output schema and the description does not explicitly state what fields or format the preview returns, but 'previews eligible completed jobs' gives a reasonable indication.

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: campaign_id is tied to search-referral-campaigns and limit has a clear description and bounds. The main description adds little beyond the schema, so the baseline of 3 is appropriate.

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 states a specific verb ('Previews'), a specific resource ('eligible completed jobs'), and a clear scope ('for one authorized referral campaign'). It also adds the crucial qualifier 'without sending or changing records,' which distinguishes it from campaign execution tools and from sibling 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 makes the usage context clear: it is a read-only preview of eligible jobs for a referral campaign, meant to inspect before sending. It does not explicitly name alternatives or give when-not-to-use conditions, but the combination of 'previews' and 'without sending or changing records' gives an agent clear context for safe selection.

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