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

Annotations provide only destructiveHint=true; the description earns credit by explaining why — it can execute ANY mutation, so effects are unbounded and potentially irreversible. It also names the endpoint hit and the optional-variables surface. It stops short of describing auth requirements, rate limits, or error/partial-failure behavior, which matters for an arbitrary-operation tool.

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?

Front-loads the critical warning ('MUTATES Memberful data') and ends with the routing directive. The middle sentence is long and slightly clause-stacked, but every element — risk, scope, endpoint, variables, alternative — earns its place.

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 passthrough with no output schema (returns are unknowable in advance), the description covers what an agent needs: what it does, the endpoint, the mutation risk, and the safer sibling. Return-shape documentation is impossible here, so the omission is acceptable, though a note on permission requirements would complete it.

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% with both parameters documented (query and variables), so the schema carries this dimension. The description only echoes 'with optional variables' without adding format guidance or examples, which is the expected baseline 3 when the schema does the heavy lifting.

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 and resource: run an arbitrary Memberful GraphQL query or mutation against the account's /api/graphql endpoint with optional variables. It explicitly distinguishes itself from the sibling memberful_query, so an agent can route between the two without opening either schema.

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?

Gives an explicit alternative and the condition that selects it: 'Prefer memberful_query for read-only calls.' The 'escape hatch' framing implies this is the fallback when no dedicated tool covers the operation, though it never explicitly says which sibling mutations to prefer, leaving some inference to the agent.

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