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

The description goes beyond the destructiveHint annotation by explicitly warning that the operation may mutate Memberful data and by disclosing that it can run 'any' mutation with no guardrails. It also names the endpoint. This is useful context, though it does not detail authentication, rate limits, or error behavior.

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 with no filler. It front-loads the mutating risk, states the tool's escape-hatch role, and closes with a clear alternative routing instruction.

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 an arbitrary GraphQL escape hatch with a simple two-parameter schema, the description gives enough context to call the tool correctly: what it runs, where it runs, and when to use the sibling instead. Since there is no output schema, the description could note that the response shape depends entirely on the GraphQL operation, but the arbitrary-operation framing implies this.

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 description coverage is 100%, so the schema already documents both query and variables parameters. The description adds only the context that variables are optional and that the operation is against a specific endpoint, which does not significantly improve parameter-level understanding beyond the schema.

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 identifies a specific action: running an arbitrary Memberful GraphQL operation, including mutations, against the account's /api/graphql endpoint. It also distinguishes itself from memberful_query by noting the read-only sibling is preferred for non-mutating calls.

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 description explicitly says to prefer memberful_query for read-only calls, which gives the agent a clear routing rule. The 'escape hatch' framing also communicates that this tool is for cases where a specialized tool does not exist or where arbitrary GraphQL is required.

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