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

The annotations already declare destructiveHint=true, readOnlyHint=false, and openWorldHint=false. The description adds useful scope by clarifying that the removal is list-specific, single-contact, and email-based, but it does not explain permanence, whether the contact remains elsewhere, or any authorization requirements.

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 short and front-loaded with the core action. It is slightly redundant, repeating "Remove a Contact from a List" as "Remove a single contact from a list by email," but the repetition is minor.

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?

With a rich input schema, an output schema, and destructive annotations already present, the description provides the essential scope and identifier needed to call the tool. The remaining gap is the lack of clarity about how this differs from archive or global unsubscribe operations.

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 email, list_id, and workspace_id. The description only restates that removal is by email from a list, adding no meaningful semantics beyond the schema baseline.

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 ("Remove a Contact") with clear scope ("from a List") and identifier ("by email"). It is distinguishable from generic deletion, but it does not explicitly differentiate itself from nearby siblings such as archive_contact or unsubscribe_lead_globally.

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 "Remove a single contact from a list by email" implies the use case: removing one list membership by email. However, it gives no explicit when-not guidance and does not name alternatives such as archive_contact, unsubscribe_lead_globally, or remove_from_blocklist.

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