Trello MCP Server

Create Webhook

create_webhook

Set up a webhook to monitor a Trello board, list, card, or member and get notified when it changes. Provide a publicly accessible callback URL to receive POST notifications.

Instructions

Create a webhook to receive notifications when a Trello model changes. The callback URL must be publicly accessible and respond to HEAD requests.

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": {
      "idModel": "<idModel>",
      "callbackURL": "<callbackURL>"
    },
    "name": "create_webhook"
  }
}

Input Schema

Name	Required	Description
`active`	No	Whether the webhook is active (default: true)
`idModel`	Yes	The ID of the model to watch (board, list, card, member, etc.)
`callbackURL`	Yes	The URL to receive webhook POST callbacks
`description`	No	Description of the webhook

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.0Sep 6, 2026

TDQS

A4.1/5.0

Behavior3/5

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

No annotations are provided, so the description carries the behavioral disclosure burden. It usefully discloses a key external constraint (callback URL must be publicly accessible and respond to HEAD requests), but does not mention side effects, permissions, idempotency, failure behavior, or what happens upon creation.

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 sentences, front-loaded with the tool's purpose, followed by a critical constraint. No filler or repetition of values already expressed in the schema.

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 mutation tool with no annotations and no output schema, the description covers the core purpose and a key prerequisite. However, it omits behavioral details like whether creation is idempotent, what response or webhook ID to expect, and whether any authorization is needed beyond normal API access. These are meaningful gaps for an agent invoking the tool.

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

Parameters4/5

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

The schema already describes all 4 parameters (100% coverage), so the baseline is 3. The description adds meaningful extra meaning by specifying that the callback URL must be publicly accessible and respond to HEAD requests, which is not stated in the schema's parameter description.

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

Purpose5/5

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

The description clearly states the action (create), the resource (webhook), and the purpose (receive notifications when a Trello model changes). This makes it immediately distinguishable from sibling tools like get_webhook, update_webhook, and delete_webhook.

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

Usage Guidelines4/5

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

The description provides clear context for when to use the tool: to register a webhook for Trello model change notifications. It also gives a prerequisite for successful use (publicly accessible callback URL that responds to HEAD requests). However, it does not explicitly mention alternatives or when not to use it.

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

Deploy Server