listmonk-mcp

Update mailing list

list_update

Modify an existing mailing list by passing only the fields to change; unspecified settings remain unchanged.

Instructions

Update a mailing list. Only the fields you pass change; the rest are kept from the current list.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "id": "<id>"
    },
    "name": "list_update"
  }
}

Input Schema

Name	Required	Description	Default
`id`	Yes
`name`	No
`tags`	No
`type`	No
`optin`	No
`description`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Nov 1, 2026

TDQS

B3.3/5.0

Behavior4/5

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

Annotations declare readOnlyHint=false, destructiveHint=false and idempotentHint=false, but say nothing about merge semantics. The description adds a genuinely non-obvious trait: omission of a field means 'keep existing value' rather than 'clear it', which is critical for a PATCH-style mutation and is consistent with idempotentHint=false. It notably omits how to clear a field (e.g. empty string vs null) or what happens if `id` does not exist.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, front-loaded with the action, and the partial-update rule placed immediately after. Zero filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 6-parameter mutation with no output schema and 0% schema coverage, the description covers only the partial-update contract. It leaves out which list fields can be changed, enum meanings, tag replacement behavior, permission requirements, and what the response contains.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% across 6 parameters, so the description carries the burden, yet it names no parameters. The required `id` is never mentioned, the two enums (`type`: public/private; `optin`: single/double) are unexplained, and array-replacement behavior for `tags` (replaced vs appended) is a real ambiguity left open.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a clear verb+resource: 'Update a mailing list', which is readily distinguished from list_create, list_get, and list_delete in the sibling set. It stops short of naming which aspects of the list are updatable (name, tags, type, optin, description), leaving that to the schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No explicit when-to-use guidance, no prerequisites (e.g. must the list exist or be owned), and no routing to alternatives such as list_create for new lists. Usage is only implied by the verb 'update'.

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