post--v3-lists-list_address-members

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

With no annotations provided, the description carries full burden for behavioral disclosure. 'Create' implies a write operation, but the description doesn't mention authentication requirements, rate limits, error conditions, or what happens on success. It doesn't explain that 'upsert' can update existing members or that 'subscribed' defaults to true—these are only in the schema.

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, efficient sentence with zero wasted words. It's appropriately sized for a creation tool and front-loads the core purpose immediately.

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 mutation tool with 6 parameters, no annotations, and no output schema, the description is inadequate. It doesn't explain what happens on success (e.g., returns member ID), error conditions, or behavioral nuances like the upsert capability. The schema covers parameters but the description fails to provide necessary operational context.

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 67% (4 of 6 parameters have descriptions), so the schema does substantial work. The description adds no parameter information beyond the tool name implying 'list_address' and 'member' creation. It doesn't clarify what 'vars' contains or provide context beyond the schema's parameter descriptions.

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 'Create a mailing list member' clearly states the verb ('Create') and resource ('mailing list member'), making the purpose immediately understandable. However, it doesn't distinguish this tool from its sibling 'put--v3-lists-list_address-members-member_address' which likely updates existing members, so it misses full sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives. With siblings like 'put--v3-lists-list_address-members-member_address' for updates and 'get--v3-lists-list_address-members' for retrieval, there's no indication of when this creation tool is appropriate versus those operations.

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