> For the complete documentation index, see [llms.txt](https://help.openloyalty.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.openloyalty.io/api-reference/custom-field-value/set-a-single-custom-field-value.md).
# Set a single custom field value
Management\
\
Sets or clears the value of a single custom field. Passing `null` as the value clears the field.
````json
{"openapi":"3.0.0","info":{"title":"Open Loyalty","version":"0.0.1"},"tags":[{"name":"Custom Field Value","description":"These endpoints allow you to set and clear custom field values on entities."}],"servers":[{"url":"http://openloyalty.localhost"}],"security":[{"Bearer":[]},{"token":[]}],"components":{"securitySchemes":{"Bearer":{"type":"http","description":"Open Loyalty has the JWT authorization.\nTo learn what a JSON Web Token is and how it works, check out Introduction to JSON Web Tokens \n\n### Obtain an access token\n\nSend a request with the parameters username and password\n\n#### Definition\n\n`POST /api/admin/login_check` [Go to definition](#operation/adminLoginCheck)\\\n`POST /api/{storeCode}/member/login_check` [Go to definition](#operation/memberLoginCheck)\n\n#### Example\n\n```bash\ncurl {HOST}/api/admin/login_check\n -H 'Content-Type: application/json;charset=UTF-8'\n -H 'Accept: application/json, text/plain, */*'\n --data-binary '{\"username\":\"admin\",\"password\":\"password\"}'\n```\n\n#### Example Response\n\n```json\n{\n \"token\":\"eyJhbGciOiJSUzI1NiIsInR5cCI6...\",\n \"refresh_token\":\"0558f8bb29948c4e54c443f...\"\n}\n```\n\n### Using JSON Web Token\n\nAdd authorization header to each request\\\n`Authorization: Bearer eyJhbGciOiJSUzI1NiIsInR5cCI6...`\\\nYou can now access any API method you want under the /api prefix.\n\n#### Example\n```bash\ncurl {HOST}/api/{storeCode}/analytics/members\n -H 'Accept: application/json'\n -H 'Content-type: application/x-www-form-urlencoded'\n -H 'Authorization: Bearer eyJhbGciOiJSUzI1NiIsInR5cCI6...'\n```\n\n### Refresh JSON Web Token\nYou can refresh token using refresh_token that was given during login.\\\nThere are two endpoints\\\nTo refresh admin token `POST /api/token/refresh` [Go to definition](#operation/tokenRefresh)\\\nTo refresh member token `POST /api/{storeCode}/token/refresh` [Go to definition](#operation/tokenRefreshMember)\n","bearerFormat":"JWT","scheme":"bearer"},"token":{"type":"apiKey","name":"X-AUTH-TOKEN","in":"header"}},"parameters":{"storeCode":{"name":"storeCode","in":"path","description":"Store code","required":true,"schema":{"type":"string"}}},"schemas":{"CustomFieldEntityType":{"type":"string","description":"Entity type the custom field is associated with.","enum":["member","direct-campaign","automation-campaign","referral-campaign","leaderboard","challenge","reward","fortune-wheel-reward"]},"SingleCustomFieldValueRequest":{"type":"object","required":["value"],"additionalProperties":false,"properties":{"value":{"anyOf":[{"type":"string","nullable":true},{"type":"integer","nullable":true},{"type":"number","nullable":true},{"type":"boolean","nullable":true},{"type":"array","nullable":true,"items":{"type":"string"}},{"type":"array","nullable":true,"items":{"type":"object"}}],"description":"Value to set. Pass null to clear the field. Type depends on the field's fieldType:\ntext → string, integer → integer, float → number, boolean → boolean,\nsingle_select → string, multi_select → array of strings.\n"}}},"ExpiredToken":{"required":["code","message"],"properties":{"code":{"type":"string"},"message":{"type":"string"}},"type":"object"},"InvalidToken":{"required":["code","message"],"properties":{"code":{"type":"string"},"message":{"type":"string"}},"type":"object"},"Unauthorized":{"required":["code","message"],"properties":{"code":{"type":"integer"},"message":{"type":"string"}},"type":"object"}},"responses":{"BadRequest":{"description":"Bad request.","content":{"application/json":{"schema":{"required":["code","message","errors"],"properties":{"code":{"type":"integer"},"message":{"type":"string"},"errors":{"type":"array","items":{"required":["message","parameters","plural","code","path"],"properties":{"message":{"type":"string"},"parameters":{},"plural":{"type":"integer","nullable":true},"code":{"type":"string"},"path":{"type":"string"}},"type":"object"}}},"type":"object"}}}},"AccessDenied":{"description":"Forbidden.","content":{"application/json":{"schema":{"required":["code","message"],"properties":{"code":{"type":"integer"},"message":{"type":"string"}},"type":"object"}}}},"NotFound":{"description":"Not found.","content":{"application/json":{"schema":{"required":["code","message"],"properties":{"code":{"type":"integer"},"message":{"type":"string"}},"type":"object"}}}}}},"paths":{"/api/{storeCode}/custom-fields/{entityType}/{entityId}/{groupKey}/{fieldKey}":{"patch":{"operationId":"_customFieldValuePatchSingle","tags":["Custom Field Value"],"summary":"Set a single custom field value","description":"
\nSets or clears the value of a single custom field.\nPassing `null` as the value clears the field.\n","parameters":[{"$ref":"#/components/parameters/storeCode"},{"name":"entityType","in":"path","required":true,"description":"Entity type","schema":{"$ref":"#/components/schemas/CustomFieldEntityType"}},{"name":"entityId","in":"path","required":true,"description":"ID of the entity to update","schema":{"type":"string"}},{"name":"groupKey","in":"path","required":true,"description":"Group key containing the field","schema":{"type":"string"}},{"name":"fieldKey","in":"path","required":true,"description":"Field key to update","schema":{"type":"string"}}],"requestBody":{"required":true,"content":{"application/json":{"schema":{"$ref":"#/components/schemas/SingleCustomFieldValueRequest"}}}},"responses":{"204":{"description":"Value set successfully"},"400":{"$ref":"#/components/responses/BadRequest"},"401":{"description":"Unauthorized","content":{"application/json":{"schema":{"anyOf":[{"$ref":"#/components/schemas/ExpiredToken"},{"$ref":"#/components/schemas/InvalidToken"},{"$ref":"#/components/schemas/Unauthorized"}]}}}},"403":{"$ref":"#/components/responses/AccessDenied"},"404":{"$ref":"#/components/responses/NotFound"}}}}}}
````
---
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