# Get an invoice series API Reference

Returns one invoice series of a company, with its code, format, counter state,
document type and whether it is the default of that type.


## GET /v1/companies/{company_id}/series/{series_id}

**Get an invoice series**

Returns one invoice series of a company, with its code, format, counter state,
document type and whether it is the default of that type.

### 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.
- **series_id** (required) in path: Series ID

### Responses

#### 200: Series retrieved successfully

**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** `InvoiceSeries`

#### 400: The request target could not be read as declared, so nothing was looked up. Three causes,
all named in `error.details`: a path or query parameter whose value does not parse as its
type (`VALIDATION_ERROR` — a UUID that is not a UUID, an unknown enum value, an empty
element in a list such as `status=ISSUED,`), a required parameter that was not sent
(`MISSING_PARAMETER`), or a header that is meant to carry an identifier and does not
(`ACTIVE_COMPANY_HEADER_INVALID`). A list parameter sent entirely empty (`status=`) is
not an error: it is the same as omitting it.

The fault is in the target, not in the content — which is what `422` is defined over.


**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 parameter 'invoice_id' has an invalid type. Expected: UUID.",
    "details": {
      "field": "invoice_id",
      "invalid_value": "deliveries",
      "expected_format": "UUID"
    }
  },
  "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 NIF 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: No series with that id under this company. A series belonging to another NIF answers
the same way: under the scope of the NIF in the path it simply does not exist.


**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")

#### 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

## 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")

## InvoiceSeries

- **id** (required) `string` (uuid): Unique series ID
- **document_type** (required) `DocumentType`: Document type associated with a series. Values mirror `InvoiceType`, so the series a document needs is named exactly like the document: - UNASSIGNED: Legacy value of series created before types existed. A series numbers only documents of its own type, so an `UNASSIGNED` series numbers none (`422 SERIES_INCOMPATIBLE_DOC_TYPE`); give it a type to keep using it. No series can be created with it or moved to it (`422 SERIES_UNASSIGNED_TYPE_NOT_ALLOWED`). The live ones were given the type they numbered most. - STANDARD: Standard invoice - SIMPLIFIED: Simplified invoice - CORRECTIVE: Corrects or cancels a previous standard invoice (R1–R4) - SIMPLIFIED_CORRECTIVE: Corrects a simplified invoice (R5). Spanish law requires R5 to be numbered apart from R1–R4, so they have a series type of their own - PROFORMA: Proforma (commercial document, non-fiscal numbering)
- **name** (required) `string`: Descriptive name of the series (example: "Main Series")
- **code** (required) `SeriesCode`: Alphanumeric series code (used in {CODIGO} variable). Allows uppercase letters, numbers, hyphens and underscores.
- **description** `string`: Optional series description (example: "Series for standard invoices")
- **format** (required) `SeriesFormat`: Format template with available variables (UPPERCASE ONLY): - {CODIGO}: Series code (e.g., "FAC") - {YYYY}: Year with 4 digits (e.g., "2025") - {YY}: Year with 2 digits (e.g., "25") - {MM}: Month with 2 digits (e.g., "01") - {NUM}: Sequential number without padding (e.g., "1") - {NUM:X}: Sequential number with padding (e.g., {NUM:4} → "0001") **REQUIRED**: Must contain at least {NUM} or {NUM:X} **IMPORTANT**: Only uppercase (rejects {yy}, {mm}, {codigo}, etc.) Valid examples: - "{CODIGO}-{YYYY}-{NUM:4}" → "FAC-2025-0001" - "{CODIGO}/{NUM:6}" → "FAC/000001" - "{YYYY}{MM}-{NUM:3}" → "202501-001" The generated number is the invoice number sent to the AEAT, which accepts at most 60 printable ASCII characters and none of `"`, `'`, `<`, `>`, `=`. A format whose longest possible number breaks that rule is rejected with `422 SERIES_FORMAT_NUMBER_TOO_LONG` or `SERIES_FORMAT_INVALID_CHARACTERS`. The counter counts as at least 9 digits, with or without padding: `{NUM:X}` is a minimum width, not a maximum.
- **counter_reset** (required) `CounterReset`: Counter reset policy: - NEVER: Counter never resets (continuous numbering) - ANNUAL: Counter resets yearly - MONTHLY: Counter resets monthly
- **initial_number** `integer` (int64): Initial number configured for this series counter: the number the series starts from. It applies only to the first period in which the series issues an invoice: with `counter_reset: ANNUAL` or `MONTHLY`, every later year or month starts at 1. With `NEVER` there is a single period, so numbering simply continues from it. (example: 1)
- **active** (required) `boolean`: Indicates whether the series is active
- **default_series** (required) `boolean`: Indicates whether this is the user's default series (only one can be)
- **numbering_locked** `boolean`: `true` once this series has issued at least one invoice. From that point the fields that drive numbering (`code`, `format`, `counter_reset`, `initial_number`) are permanently locked and any attempt to change them is rejected — numbering can only be adjusted **before** the first invoice of a series. Cosmetic fields (`name`, `description`) remain editable. To use a different numbering, create a new series.
- **created_at** `string` (date-time): Creation date
- **next_number** `integer` (int64): Next invoice number that will be assigned for this series
- **updated_at** `string` (date-time): Last update date

## 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"})

## DocumentType

Document type associated with a series. Values mirror `InvoiceType`,
so the series a document needs is named exactly like the document:
- UNASSIGNED: Legacy value of series created before types existed. A series numbers only
  documents of its own type, so an `UNASSIGNED` series numbers none
  (`422 SERIES_INCOMPATIBLE_DOC_TYPE`); give it a type to keep using it. No series can be
  created with it or moved to it (`422 SERIES_UNASSIGNED_TYPE_NOT_ALLOWED`). The live
  ones were given the type they numbered most.
- STANDARD: Standard invoice
- SIMPLIFIED: Simplified invoice
- CORRECTIVE: Corrects or cancels a previous standard invoice (R1–R4)
- SIMPLIFIED_CORRECTIVE: Corrects a simplified invoice (R5). Spanish law requires R5 to be
  numbered apart from R1–R4, so they have a series type of their own
- PROFORMA: Proforma (commercial document, non-fiscal numbering)

Type: `string` — one of: UNASSIGNED, STANDARD, SIMPLIFIED, CORRECTIVE, SIMPLIFIED_CORRECTIVE, PROFORMA

## SeriesCode

Alphanumeric series code (used in {CODIGO} variable).
Allows uppercase letters, numbers, hyphens and underscores.

Type: `string`

## SeriesFormat

Format template with available variables (UPPERCASE ONLY):
- {CODIGO}: Series code (e.g., "FAC")
- {YYYY}: Year with 4 digits (e.g., "2025")
- {YY}: Year with 2 digits (e.g., "25")
- {MM}: Month with 2 digits (e.g., "01")
- {NUM}: Sequential number without padding (e.g., "1")
- {NUM:X}: Sequential number with padding (e.g., {NUM:4} → "0001")

**REQUIRED**: Must contain at least {NUM} or {NUM:X}
**IMPORTANT**: Only uppercase (rejects {yy}, {mm}, {codigo}, etc.)

Valid examples:
- "{CODIGO}-{YYYY}-{NUM:4}" → "FAC-2025-0001"
- "{CODIGO}/{NUM:6}" → "FAC/000001"
- "{YYYY}{MM}-{NUM:3}" → "202501-001"

The generated number is the invoice number sent to the AEAT, which accepts at most 60
printable ASCII characters and none of `"`, `'`, `<`, `>`, `=`. A format whose longest
possible number breaks that rule is rejected with `422 SERIES_FORMAT_NUMBER_TOO_LONG` or
`SERIES_FORMAT_INVALID_CHARACTERS`. The counter counts as at least 9 digits, with or without
padding: `{NUM:X}` is a minimum width, not a maximum.

Type: `string`

## CounterReset

Counter reset policy:
- NEVER: Counter never resets (continuous numbering)
- ANNUAL: Counter resets yearly
- MONTHLY: Counter resets monthly

Type: `string` — one of: NEVER, ANNUAL, MONTHLY


---

Full OpenAPI spec: https://docs.beel.es/api/openapi