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

# Replace a partner's companion-guide **overlay** (extra segments + element

> overrides) without touching any other field — the save path behind the visual mapping editor…

overrides) without touching any other field — the save path behind the
visual mapping editor. Validate-before-publish is enforced: an overlay with
blocking errors is rejected. An empty overlay clears it.

### Path parameters

<ParamField path="id" type="string" required>
  Partner ID
</ParamField>

### Request body

`PartnerOverlay`

<ParamField body="element_overrides" type="ElementOverride[]">
  Force an element's value on the first matching segment of an outbound transaction (optionally scoped to a set) — e.g. a fixed qualifier.
</ParamField>

<ParamField body="extra_segments" type="OverlaySegment[]">
  Extra segments appended to outbound transactions (optionally scoped to a transaction set) — e.g. a partner-required `REF`/`N9`/`DTM`.
</ParamField>

### Response

No response body. Overlay saved (returns the redacted partner + validation warnings).

### Status codes

| Code  | Meaning                                                            |
| ----- | ------------------------------------------------------------------ |
| `200` | Overlay saved (returns the redacted partner + validation warnings) |
| `422` | Overlay has blocking errors                                        |

<RequestExample>
  ```bash cURL theme={null}
  curl --request PUT \
    --url 'https://edi.stateset.com/v1/partners/{id}/overlay' \
    --header 'Authorization: Bearer YOUR_API_KEY' \
    --header 'Content-Type: application/json' \
    --data '{
    "element_overrides": [
      {
        "element": 1,
        "segment": "string",
        "transaction_set": "string",
        "value": "49.00"
      }
    ],
    "extra_segments": [
      {
        "elements": [],
        "tag": "priority",
        "transaction_set": "string"
      }
    ]
  }'
  ```
</RequestExample>