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

Description correctly indicates a write operation (create) and adds conditional behavior (if absent). Annotations already show non-read-only, non-destructive, so description adds specific context without contradiction.

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?

Extremely concise single sentence with no unnecessary words. Perfectly front-loaded and efficient.

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 tool with no parameters and no output schema, the description is complete regarding purpose and behavior. Could mention return value but not required.

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?

No parameters exist, so schema coverage is 100%. With 0 parameters, baseline is 4, and the description adds no param info as none are needed.

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 clearly states the action (create), resource (referral code), and scope (authenticated user). It distinguishes from siblings like 'retrieve_or_create_business_referral_code' which targets business codes.

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 phrase 'if absent' implies conditional creation, but no explicit guidance on when to use this vs. alternatives like 'get_referral_code_details' or 'retrieve_or_create_business_referral_code' is provided.

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