# Add an option to a custom field API Reference Adds a value to the options of this custom field, for one customer or, without `customer_id`, common to every customer. Use it to seed a catalogue before the first invoice; values used on invoices are added on their own. - **Equivalent values:** two values are equivalent when they match ignoring case, accents and repeated spaces. If the field already has an equivalent option — of that customer or a common one — no option is created: the response is `200` with the existing option, and its text is kept. Only when nothing equivalent exists is the option created, with `201`. - **Archived options:** an equivalent archived option counts as existing. It comes back with `200` and stays archived; reactivate it with `PATCH /v1/companies/{company_id}/custom-fields/{key}/options/{option_id}`. - **Suggestions off:** a field with `suggest_values: false` accepts options in the same way, so a catalogue can be prepared before turning suggestions on. They are not offered on invoices while the setting is off. ## POST /v1/companies/{company_id}/custom-fields/{key}/options **Add an option to a custom field** Adds a value to the options of this custom field, for one customer or, without `customer_id`, common to every customer. Use it to seed a catalogue before the first invoice; values used on invoices are added on their own. - **Equivalent values:** two values are equivalent when they match ignoring case, accents and repeated spaces. If the field already has an equivalent option — of that customer or a common one — no option is created: the response is `200` with the existing option, and its text is kept. Only when nothing equivalent exists is the option created, with `201`. - **Archived options:** an equivalent archived option counts as existing. It comes back with `200` and stays archived; reactivate it with `PATCH /v1/companies/{company_id}/custom-fields/{key}/options/{option_id}`. - **Suggestions off:** a field with `suggest_values: false` accepts options in the same way, so a catalogue can be prepared before turning suggestions on. They are not offered on invoices while the setting is off. ### Authentication Accepts any of: - `ApiKeyAuth` (HTTP bearer, token format `beel_sk_*`) ### Parameters - **company_id** (required) in path `string`: Unique identifier (UUID) of the company the operation acts on — its identifier, not its NIF. It is the only source of context: the account that owns it is derived from it, and the `BeeL-Active-Company` header plays no part. A company you do not reach answers `403`, and so does a company that does not exist, so the existence of a company in another account is never disclosed. - **key** (required) in path: Key of the custom field: lowercase letters, digits and `_`, up to 64 characters. A key outside that format answers `422`. - **Idempotency-Key** (optional) in header `string`: Idempotency key to prevent duplicates in sensitive operations. - Any unique client-generated string (e.g. an order id). A UUID also works but is not required - Allowed characters: letters, digits, `_` and `-` (max 255 chars) - Retrying with the same key replays the first response when it was a success (2xx) or a server error (5xx): same status and body, plus the header `Idempotency-Replay: true`. After a 5xx, check whether the operation took effect before retrying with a **new** key - A 4xx is not stored: the key is released, so the corrected request can reuse it - Stored responses expire 24 hours after processing The key is scoped per user and environment, and bound to the request body, so retrying after a network timeout replays the stored response instead of repeating the operation. | Status | Code | When | |---|---|---| | `400` | `INVALID_IDEMPOTENCY_KEY` | The key breaks the format rules above. | | `409` | `IDEMPOTENCY_KEY_PROCESSING` | The first request is still in flight. Wait for the `Retry-After` seconds (2) and retry with the same key. | | `409` | `IDEMPOTENCY_KEY_MISMATCH` | The key was already used with a **different** body. Use a new key. | ### Request Body Required. **Content `application/json`:** - **value** (required) `string`: Text of the option. Leading and trailing spaces are removed; a value that is empty after that answers `422`. Two values are equivalent when they match ignoring case, accents and repeated spaces (`Gran Via 12` and `gran vía 12`). (example: "Gran Vía 12") - **customer_id** `string` (uuid): Customer of the company the option belongs to. Omit it for an option common to every customer. (example: "4f244735-980b-4d9c-80e8-6331fa0b1958") ### Responses #### 200: An equivalent option already existed; this is that option, unchanged. **Content `application/json`:** - **success** (required) `boolean`: No description (example: true) - **data** (required): The payload. An object for a single resource; an object holding the named collection (and its `pagination`) for a listing. Never a bare array at this level in v1. - **meta** `ResponseMeta` - **data** `CustomFieldOption`: A value of a custom field, offered when filling it in. An option belongs to one customer or, without `customer_id`, is common to every customer of the company. #### 201: The option was created. **Headers:** - `Location` `string`: URI of the created resource — its canonical GET (`/v1/companies/{company_id}/...` or `/v1/accounts/{account_id}/...`). **Content `application/json`:** - **success** (required) `boolean`: No description (example: true) - **data** (required): The payload. An object for a single resource; an object holding the named collection (and its `pagination`) for a listing. Never a bare array at this level in v1. - **meta** `ResponseMeta` - **data** `CustomFieldOption`: A value of a custom field, offered when filling it in. An option belongs to one customer or, without `customer_id`, is common to every customer of the company. #### 400: Bad request. From a dashboard session, a `BeeL-Environment` header whose value is not a known environment answers `ENVIRONMENT_HEADER_INVALID`, with the header named in `error.details` (`{"BeeL-Environment": "invalid"}`); it is never read as production. `BUSINESS_RULE_VIOLATION` is the generic answer to an operation the resource does not admit in its current state when that state has no code of its own. It carries no `details`; read the resource again before retrying. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "BAD_REQUEST", "message": "Invalid request" }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### 401: Missing or invalid authentication. Like every other error, `message`/`detail` is localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English when the header is missing or asks for none of those. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "UNAUTHORIZED", "message": "Authentication is required to access this resource" }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### 403: Your account does not own or manage this company, or does not hold the required access over it. A company that does not exist answers the same way. That case answers `error.code` `ACTIVE_COMPANY_NOT_ACCESSIBLE`. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") #### 404: Two causes, told apart by `error.code`: `CUSTOM_FIELD_NOT_FOUND` (this company has no custom field with this `key`) and `INVOICE_CLIENT_NOT_FOUND` (the `customer_id` of the body is not a customer of this company, or was deleted). **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") #### 409: The request is well formed but collides with the state that is already there. Three families, told apart by `error.code`: - **Uniqueness** — something with that identity already exists (`CLIENT_DUPLICATE`, `PRODUCT_DUPLICATE`, `SERIES_CODE_DUPLICATED`, `NIF_ALREADY_REGISTERED`, `MEMBER_ALREADY_IN_ACCOUNT`, `INVOICE_DUPLICATE_EXTERNAL_REFERENCE`). - **Lifecycle** — the transition does not apply from where the resource is (`INVOICE_ALREADY_VOIDED`, `PROFORMA_ALREADY_CONVERTED`, `CLIENT_HAS_INVOICES`, `RECURRING_ALREADY_ENDED`, `CUSTOM_FIELD_ARCHIVED` — the custom field is archived and cannot be assigned, `RECURRING_OCCURRENCE_ALREADY_CONSUMED` — the occurrence the recurring template points at has already been billed; read its history instead of retrying). Read the resource before retrying: the state you assumed is not its state. - **Concurrency and idempotency** — another write got there first (`CONCURRENT_MODIFICATION`), or the `Idempotency-Key` you sent is still in flight (`IDEMPOTENCY_KEY_PROCESSING`, retry after a moment) or was already used for a different body (`IDEMPOTENCY_KEY_MISMATCH`, use a new key). `CONFLICT` is the generic fallback of the uniqueness family, when the uniqueness that was violated has no code of its own. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "CONCURRENT_MODIFICATION", "message": "The resource was modified by another request; read it again and retry" }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### 422: `VALIDATION_ERROR` — the body parses but a value is not acceptable. `details` is a flat map from the offending property's name (in the contract's `snake_case`, nested paths joined with a dot, e.g. `recipient.address.postal_code`) to a message describing what is wrong with it, one entry per property. When the rejected value is one outside an enum's vocabulary, `details` instead follows `FieldDeserializationError` (`field`, `invalid_value`, `allowed_values`). Two more codes share this status for a value that passes the contract but does not fit where it is stored: `VALUE_TOO_LONG` (a text longer than its column holds) and `VALUE_OUT_OF_RANGE` (a number outside what its column holds). Nothing was written. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "VALIDATION_ERROR", "message": "The provided data is not valid.", "details": { "legal_name": "The field 'legal_name' cannot be empty", "recipient.address.postal_code": "Contains invalid characters." } }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### 429: Rate limit exceeded. `RATE_LIMIT_EXCEEDED` when the request rate of your credential is over its limit; `TOO_MANY_REQUESTS` when an email the operation sends is held back because too many went out to that recipient in a short time. Either way, retry after the `Retry-After` seconds. `QUOTA_EXCEEDED` is the other `429`: the operation would go over a quota of your plan for the current period (issued invoices, for instance). Retrying does not help until the quota resets or the plan changes. `error.details` carries `feature_code`, `current_usage`, `quota_limit` and `reset_date`, and `RateLimit-Reset` the seconds until the reset when it is known. **Headers:** - `Retry-After` `integer`: Seconds until the rate limit resets - `RateLimit-Limit` `integer`: Maximum requests allowed in the window - `RateLimit-Remaining` `integer`: Remaining requests in the current window - `RateLimit-Reset` `integer`: Seconds until the current window resets **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "RATE_LIMIT_EXCEEDED", "message": "Too many requests. Please try again in 60 seconds." }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### 500: Internal server error **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "INTERNAL_ERROR", "message": "Internal server error" }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` #### default: Any status code the operation does not list above. Every operation declares it, so a generated client always has a branch to fall into and never loses the cause of a failure it did not anticipate. This is where the transport-level answers land — `405`, `406`, `415` and `429` — together with any status a future version of the API starts returning. All of them carry the same error envelope as the codes listed explicitly, so `error.code` is what tells them apart: switching on the status code alone is not enough. See «Transport-level errors» in the API description for when each one is produced. A `402` carrying `SUBSCRIPTION_REQUIRED` lands here when the account has no active subscription. `error.details` says why and what to do: `current_status` (absent if it never had one), `required_permission` and `action`. A `503` carrying `SERVICE_UNAVAILABLE` lands here too, with a `Retry-After` header: a dependency of BeeL itself (the database, the email provider) was momentarily unavailable and nothing was done. Retry after those seconds. A `502` carrying `EXTERNAL_SERVICE_ERROR` also lands here: an outbound integration the operation depends on failed or did not answer in time. It is a transient condition — retry with the same `Idempotency-Key` where the operation accepts one. One exception to the envelope: a failure of the network edge that never reaches the application (`502`, `503`, `504`, `524`) is generated by Cloudflare and its body is not BeeL's — it may not even be JSON. Treat those as "no answer", and retry. **Content `application/json`:** - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") **Example:** ```json { "success": false, "error": { "code": "UNSUPPORTED_MEDIA_TYPE", "message": "Unsupported media type: text/plain. Supported: application/json" }, "meta": { "timestamp": "2025-01-15T10:30:00Z", "request_id": "4bf92f3577b34da6a3ce929d0e0e4736" } } ``` --- # Related Schema Definitions ## CreateCustomFieldOptionRequest A value to add to the options of the field, for one customer or, without `customer_id`, common to every customer. - **value** (required) `string`: Text of the option. Leading and trailing spaces are removed; a value that is empty after that answers `422`. Two values are equivalent when they match ignoring case, accents and repeated spaces (`Gran Via 12` and `gran vía 12`). (example: "Gran Vía 12") - **customer_id** `string` (uuid): Customer of the company the option belongs to. Omit it for an option common to every customer. (example: "4f244735-980b-4d9c-80e8-6331fa0b1958") ## CustomFieldOptionResponse - **success** (required) `boolean`: No description (example: true) - **data** (required): The payload. An object for a single resource; an object holding the named collection (and its `pagination`) for a listing. Never a bare array at this level in v1. - **meta** `ResponseMeta` - **data** `CustomFieldOption`: A value of a custom field, offered when filling it in. An option belongs to one customer or, without `customer_id`, is common to every customer of the company. ## SuccessResponse The envelope every successful JSON response of the BeeL. API is wrapped in. There are no bare resources in v1 and none are planned: the payload always hangs off `data`. - A **single resource** is an object in `data`. - A **collection** hangs off a named key inside `data`, together with its `pagination`, also inside `data` — `data: {invoices: [...], pagination: {...}}`. - A collection carries `pagination` unless its operation declares itself a **closed catalogue**: a fixed, bounded list with nothing to page through. The declaration is explicit in the operation; a missing `pagination` is never something to infer. - `GET /v1/accounts` pages by cursor (`data: {accounts: [...], next_cursor}`). It is a documented variant of pagination, not another envelope. Putting the array straight into `data` with `pagination` as its sibling is the shape a v2 would adopt; v1 is not being flipped to it. - **success** (required) `boolean`: No description (example: true) - **data** (required): The payload. An object for a single resource; an object holding the named collection (and its `pagination`) for a listing. Never a bare array at this level in v1. - **meta** `ResponseMeta` ## ResponseMeta - **timestamp** `string` (date-time): No description (example: "2025-01-15T10:30:00Z") - **request_id** `string`: No description (example: "4bf92f3577b34da6a3ce929d0e0e4736") ## CustomFieldOption A value of a custom field, offered when filling it in. An option belongs to one customer or, without `customer_id`, is common to every customer of the company. - **id** (required) `string` (uuid): Unique identifier of the option. (example: "c3d4e5f6-a7b8-4c9d-8e0f-1a2b3c4d5e6f") - **value** (required) `string`: Text of the option, exactly as it is shown and copied onto an invoice. (example: "Gran Vía 12") - **customer_id** (required) `string` (uuid): Customer the option belongs to, or `null` for an option common to every customer. It is set when the option is created and never changes. (example: "4f244735-980b-4d9c-80e8-6331fa0b1958") - **is_archived** (required) `boolean`: An archived option is no longer offered and is left out of listings unless `include_archived=true`. Invoices that already carry its text keep it. (example: false) ## ErrorResponse Error response shared by all BeeL. APIs. The payload carries **two contracts at once** (additive, non-breaking): - **Legacy** (`success`, `error.{code,message,details}`, `meta`) — kept intact for existing consumers. - **RFC 9457** (`type`, `title`, `detail`, `instance`) — new fields for integrators following Problem Details for HTTP APIs. The `type` URI is the stable, shareable link to the error's documentation page (e.g. `https://docs.beel.es/errors/{code}`). Future migration: the legacy fields will be deprecated via `Deprecation`/`Sunset` headers after a sufficient adoption window, and the response Content-Type will move to `application/problem+json`. - **success** (required) `boolean`: No description (example: false) - **error** (required) `ErrorDetail` - **meta** `ResponseMeta` - **type** `string` (uri): Stable URI that identifies the problem type and where the integrator will find its documentation. (example: "https://docs.beel.es/errors/INVOICE_NO_LINES") - **title** `string`: Short summary of the problem type. Stable between occurrences of the same `type`. (example: "INVOICE_NO_LINES") - **detail** `string`: Specific message for this occurrence, localized according to `Accept-Language` (`es`, `en`, `ca`); defaults to English. Matches the legacy `error.message`. (example: "The invoice must have at least one line") - **instance** `string` (uri-reference): URI that identifies the specific occurrence of the problem — typically the path of the affected resource. (example: "/v1/invoices/abc-123") ## ErrorDetail - **code** (required) `string`: No description (example: "VALIDATION_ERROR") - **message** (required) `string`: No description (example: "The provided data is not valid") - **details** `object`: No description (example: {"field":"specific error message"}) --- Full OpenAPI spec: https://docs.beel.es/api/openapi