# update_flow

Returns ok/version or an error with validation details..

## Purpose

Rename a flow and/or replace its definition. On a LIVE flow this creates a new version; merchants already in the flow finish on the version they entered with.

## Credentials and scope

Owner workspace credential. The credential determines tool visibility. For tools with appId, use the HeyCrust app UUID from list_apps; the dashboard app selector does not supply MCP arguments for you.

## Inputs

- `flowId`: required; string; format: uuid — Flow id from list_flows.
- `name`: optional; string; minLength: 1; maxLength: 80
- `definition`: optional complete FlowDefinition object. See the [nested definition contract](/docs/mcp/flow-definition); structure and business checks are validated by the handler.

## Example request

The identifiers and merchant are fictional. Replace them with records returned for your own workspace; this example is schema-checked, not a promise that the fictional record exists.

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "update_flow",
    "arguments": {
      "flowId": "11111111-1111-4111-8111-111111111111",
      "name": "Welcome follow-up"
    }
  }
}
```

POST this JSON to `https://heycrust.com/api/mcp` with `Content-Type: application/json` and `Authorization: Bearer <YOUR_CREDENTIAL>`. The tool result normally contains JSON encoded as text in `result.content`; inspect JSON-RPC errors and `result.isError` before using it.

## Result

Returns ok/version or an error with validation details.

## Effects and verification

Renames a Flow or saves a replacement definition as a new version. Existing runs retain their saved version. Read get_flow again and inspect the saved scope/version before activation.

## Troubleshooting

A missing tool can mean that the credential lacks its catalog or required scopes. Invalid arguments are different from unavailable source data or a record outside the workspace. A handler can return a business error even when the argument schema is valid. Read [MCP overview](/docs/mcp) and [Help](/docs/help).