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

Annotations already mark this as read-only, and the description adds meaningful behavioral detail by listing the returned fields: profile, Stripe customer id, unrestricted-access flag, total spend, metadata, address, and subscriptions. It also notes the underlying GraphQL structure, providing useful context beyond the 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?

The description is a single dense sentence that front-loads the core action before enumerating what is returned. Every clause adds useful information, and the GraphQL note is a concise implementation anchor with no wasted words.

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 one-parameter read tool, the description is complete: it states the operation, identifies the input, and enumerates the output fields despite there being no output schema. Combined with the readOnlyHint annotation, an agent has everything needed to select and invoke this tool correctly.

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 input schema already fully documents the single id parameter with 'The member id.' The description says 'by id' but adds no additional semantic detail about id format, required permissions, or related identifiers. Since schema coverage is 100%, baseline 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 starts with a specific verb and resource: 'Fetch one Memberful member by id,' which clearly distinguishes this from sibling tools like list_members or get_subscription. It also enumerates exactly what data is returned, making the tool's 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?

The phrase 'Fetch one Memberful member by id' makes the primary use case clear: retrieve a single member record when the id is known. It does not explicitly name alternatives or state when not to use it, but the contrast with list_members and get_subscription is strongly implied.

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