polar_register_user

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

Annotations already indicate readOnly=false and idempotent=true. Description adds that the tool creates a link between application and Polar user, which is a useful side-effect note, but it omits other behavioral details like required user consent or auth state. With annotations covering the main flags, a 3 is appropriate.

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?

Two succinct sentences, no redundant fluff, and the core action and consequence are conveyed efficiently.

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?

The tool's purpose depends heavily on the Polar OAuth flow (sibling tools include authorization and code exchange), but the description does not explain how the user is identified, what credentials are needed, or the proper sequence. No output schema is provided, so the result shape is also unknown. This leaves significant context gaps for an agent.

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 coverage is 100% (one parameter 'format' fully documented with enum, default, and description). The description does not add extra parameter context beyond the schema, but the baseline holds. The mismatch between the registration operation and only a format parameter is a schema completeness concern, not a parameter-semantics gap.

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?

States a specific verb ('Register') and resource ('new user with the Polar AccessLink API') and clarifies it creates a link. Clearly distinguishes from sibling tools like polar_get_user and polar_exchange_authorization_code.

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?

No guidance on when to use this tool vs alternatives. Does not mention prerequisites such as having an authorization code or being authenticated, nor when polar_exchange_authorization_code or polar_get_user would be more appropriate.

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