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

The annotations already disclose that this is a destructive, non-idempotent write, and the description adds meaningful context: the 1000-member cap and the fact that campaigns that already captured addresses retain them. It does not explain partial-failure behavior or authorization requirements, but it adds useful side-effect information 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 compact, front-loaded statement with no wasted text. The write marker, action, ID source, limit, and side-effect note are all packed 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?

For a three-parameter mutation tool with rich annotations and no output schema, this description covers the key operational details: what it removes, where the member IDs come from, the limit, and campaign retention behavior. The main remaining gap is not specifying id/uuid mutual exclusivity and error behavior for invalid or partial IDs.

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 0%, so the description must carry parameter meaning. It explains that email_list_member_ids are IDs from list_email_list_members with a maximum of 1000, and that the target saved list is identified by either email_list_id or email_list_uuid. It leaves some ambiguity about whether exactly one of the list ID fields is required, but it substantially compensates for the bare 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 states a specific verb and resource: it removes email list members from a saved list. It also clarifies that member IDs come from list_email_list_members, which distinguishes it from sibling listing and add-member tools.

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?

It gives clear usage context by naming the source of email_list_member_id values and the 1000-member limit. It does not explicitly name add_email_list_members as the alternative for the opposite operation, but the intended use is clear from the action and constraints.

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