Create a new contact list to organize email recipients. Returns a list ID for adding contacts in subsequent steps.
Create a contact list. Returns the list with its id (lst_…); add contacts with addListContacts. Requires a management session token.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes |
Changes observed during successful MCP inspections.
v0.20.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the annotations, it discloses the return shape ('list with its id (lst_…)') and the auth requirement ('management session token'). It does not discuss duplicates, limits, or errors, but for a simple create operation the added context is meaningful.
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?
Two sentences, front-loaded with the action, with no filler. Each clause adds useful information: action, return value, next step, and auth requirement.
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 one-parameter creation tool with no output schema, this is complete: the return value is specified, the auth requirement is stated, and the natural follow-up action is mentioned. An agent can invoke this tool correctly with minimal guessing.
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?
There is only one required parameter, name, and its meaning is reasonably inferable from the property name and 'contact list.' However, the description never explicitly explains the name parameter or any constraints, and the schema has 0% description coverage, so this is a minor gap.
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 states the specific verb ('Create'), the resource ('a contact list'), and the expected return (the list with its id). It also distinguishes itself from the closely related add-contacts operation by explicitly referencing addListContacts.
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 gives useful procedural context: create the list first, then add contacts via addListContacts. It also notes the auth prerequisite. It does not explicitly state exclusions versus other list-manipulation siblings, but the workflow is clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.