> ## Documentation Index
> Fetch the complete documentation index at: https://velt.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Update Definition

Use this API to update an existing workflow definition. Atomically increments the version, snapshots the prior content, and rejects if the stored version mismatches `ifVersion`. In-flight executions keep running on the version they started with.

# Endpoint

`POST https://api.velt.dev/v2/workflow/definitions/update`

# Headers

<ParamField header="x-velt-api-key" type="string" required>
  Your API key.
</ParamField>

<ParamField header="x-velt-auth-token" type="string" required>
  Your [Auth Token](/security/auth-tokens).
</ParamField>

# Body

#### Params

Accepts every field from [Create Definition](/api-reference/rest-apis/v2/approval-engine/definitions/create-definition) plus:

<ParamField body="data" type="object" required>
  <Expandable title="properties">
    <ParamField body="definitionId" type="string" required>
      The definition to update.
    </ParamField>

    <ParamField body="ifVersion" type="integer" required>
      Optimistic-locking version. Must equal the stored definition's current `version`. The update is rejected if the stored version has advanced since you last read it.
    </ParamField>

    <ParamField body="name" type="string">
      1–200 chars.
    </ParamField>

    <ParamField body="description" type="string">
      0–2000 chars.
    </ParamField>

    <ParamField body="nodes" type="array">
      1–100 nodes.
    </ParamField>

    <ParamField body="edges" type="array">
      0–500 edges.
    </ParamField>

    <ParamField body="groups" type="array">
      0–100 parallel-group definitions.
    </ParamField>

    <ParamField body="loops" type="array">
      0–20 loop region declarations. See [loop regions](/ai/approval-engine/customize-behavior#loop-regions) on the Customize Behavior page for the full schema and linter rules.
    </ParamField>

    <ParamField body="triggers" type="array">
      0–50 trigger declarations. Each trigger has the shape `{ triggerId, eventName?, filters? }`:

      | Field       | Type   | Required | Description                                                                                     |
      | ----------- | ------ | -------- | ----------------------------------------------------------------------------------------------- |
      | `triggerId` | string | yes      | 1–128 chars. Stable identifier for this trigger.                                                |
      | `eventName` | string | no       | ≤ 128 chars. The event name your application emits when the workflow should dispatch.           |
      | `filters`   | object | no       | Free-form filter map; consumed by your dispatch wrapper to decide whether to fire this trigger. |

      Triggers are descriptive metadata in v1 — the engine does not auto-dispatch from them. Use them to label which definition belongs to which application event so your own dispatcher can resolve `eventName → definitionId`.
    </ParamField>

    <ParamField body="tags" type="string[]">
      0–20 tags, each ≤ 64 chars.
    </ParamField>

    <ParamField body="custom" type="object">
      Free-form metadata.
    </ParamField>

    <ParamField body="organizationId" type="string">
      Required when scoped to an organization or document.
    </ParamField>

    <ParamField body="documentId" type="string">
      Required when scoped to a document.
    </ParamField>
  </Expandable>
</ParamField>

<Note>
  Every successful update increments `version` and snapshots the prior content. In-flight executions are immune to updates — they keep running on the pinned `definitionVersion` from their dispatch.
</Note>

## **Example Requests**

#### Rename a definition

```JSON theme={null}
{
  "data": {
    "definitionId": "marketing-copy-approval",
    "ifVersion": 1,
    "name": "Marketing copy approval (Q2 revision)"
  }
}
```

# Response

#### Success Response

```JSON theme={null}
{
  "result": {
    "definitionId": "marketing-copy-approval",
    "name": "Marketing copy approval (Q2 revision)",
    "description": null,
    "version": 2,
    "scope": { "level": "apiKey", "organizationId": null, "documentId": null },
    "nodes": [ /* current */ ],
    "edges": [ /* current */ ],
    "groups": [ /* current */ ],
    "triggers": null,
    "tags": null,
    "custom": null,
    "createdAt": 1731432000000,
    "updatedAt": 1731518400000,
    "status": "active"
  }
}
```

#### Failure Response

```JSON theme={null}
{
  "error": {
    "message": "ERROR_MESSAGE",
    "status": "FAILED_PRECONDITION"
  }
}
```

**Errors:** `NOT_FOUND` (definition does not exist) / `FAILED_PRECONDITION` (`ifVersion` mismatch) / `INVALID_ARGUMENT` (schema or linter failure).

<ResponseExample>
  ```js theme={null}
  {
    "result": {
      "definitionId": "marketing-copy-approval",
      "name": "Marketing copy approval (Q2 revision)",
      "description": null,
      "version": 2,
      "scope": { "level": "apiKey", "organizationId": null, "documentId": null },
      "nodes": [],
      "edges": [],
      "groups": [],
      "triggers": null,
      "tags": null,
      "custom": null,
      "createdAt": 1731432000000,
      "updatedAt": 1731518400000,
      "status": "active"
    }
  }
  ```
</ResponseExample>