set_campaign_content

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

Disclosures: overwrites all previous content, authenticates via API key, subject to rate limits (max 10 concurrent), respects read-only/dry-run modes, returns error if not draft, large payload timeout (under 200KB). No annotations exist, so description covers behavioral aspects thoroughly.

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?

Efficient two-paragraph structure: first paragraph states purpose and usage context, second describes parameters and return format. Front-loaded with key purpose. Example included. Every sentence adds value without 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 simplicity (2 required params, output schema exists), the description covers all needed context: authentication, rate limits, prerequisites, parameter details, return format, error conditions, and workflow integration. No gaps.

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?

With 0% schema description coverage, the description adds full semantics: campaign_id explained with examples and source functions, html explained with validity, inline CSS, merge tags, and size limit. This completely compensates for the schema's lack of descriptions.

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 'Set the full HTML body of a campaign draft, replacing any existing content entirely.' It clearly identifies the action and resource, and distinguishes from sibling tools like update_campaign (for settings) and create_campaign (for initial creation).

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 states when to use: after create_campaign, before sending; provides workflow (create_campaign -> set_campaign_content -> send_test_email -> send_campaign); specifies when not to use: use update_campaign for settings; mentions prerequisites (draft status) and constraints (rate limits, dry-run).

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