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

With no annotations provided, the description carries full responsibility and does an excellent job: it discloses variable substitution support, UTM auto-tagging on send, automatic legal footer with unsubscribe link, return values (campaign ID and recipient count), draft status, and the requirement of confirm: true. These are meaningful behavioral details beyond a simple 'create'.

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 dense but well-structured: purpose, variable substitution, audience selection, send-time side effects, output, workflow, and confirmation requirement. Each sentence adds valuable information; no fluff 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?

Given the tool's complexity (10 params, nested adHocFilters, no annotations/output schema), the description covers a lot: audience types, UTM behavior, return values, and the draft workflow. Gaps remain for orgSlug and emailSubject, and the type parameter's interaction with the 'email campaign' description is not addressed, so it's not fully complete but is very usable.

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?

The description adds substantial meaning beyond the bare schema: it explains audienceType/audienceId combinations, emailBody as HTML, the confirm flag, and name's role in generating the UTM slug. However, it omits orgSlug (a required param), emailSubject, type, and apiKey. With schema description coverage at 0%, the description partially compensates but leaves some parameters unexplained.

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 opens with a clear action and resource: 'Create a new email campaign with HTML body to send to a segmented audience.' It also distinguishes itself from the sibling comms_send_campaign by noting the campaign starts as a draft, making the purpose unambiguous.

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?

Explicitly instructs to use comms_send_campaign after creation ('Campaign starts as draft — use comms_send_campaign to execute') and provides detailed audience selection instructions (predefined vs adhoc, specific audienceId values). This gives clear when-to-use guidance and names the alternative.

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