Lob Letters API is one of 48 APIs that Lob publishes on the APIs.io network, described by a machine-readable OpenAPI specification.
Tagged areas include Letters. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.
This API exposes
2 operations
across 1 path,
and defines 80 schemas.
It is described by OpenAPI 3.2.0, at version 1.20.2.
Requests are made against a single base URL, https://api.lob.com/v1.
The identity and technical contract details declared by the specification.
qr_code
object
Customize and place a QR code on the creative at the required position.
10 properties
3 required
user_provided
stringnull
Accepts an envelope ID for any customized envelope with available inventory. If no inventory is available for the specified ID, the letter will not be sent, an…
evnt_id
string
Unique identifier prefixed with evnt.
error
object
Lob uses RESTful HTTP response codes to indicate success or failure of an API request. In general, 2xx indicates success, 4xx indicate an input error, and 5xx…
1 property
1 required
card_id
string
Unique identifier prefixed with card.
return_envelope_returned
object
4 properties
buckslip_description
stringnull
Description of the buckslip.
buckslip_id
string
Unique identifier prefixed with bck.
ltr_file
Notes: - HTML merge variables should not include delimiting whitespace. - All pages of a supplied PDF file must be sized at 8.5"x11", while supplied HTML will…
tmpl_id
string
Unique identifier prefixed with tmpl. ID of a saved [HTML template](section/HTML-Templates).
object
string
Value is resource type.
vrsn_id
string
Unique identifier prefixed with vrsn.
custom_envelope_returned
objectnull
A nested custom envelope object containing more information about the custom envelope used or null if a custom envelope was not used.
3 properties
3 required
ltr_use_type
stringnull
The use type for each mailpiece. Can be one of marketing, operational, or null. Null usetype is only allowed if an account default usetype is selected in Accou…
remote_file_url
string
The location of a remote file. Remote URLs have a 5 MB file size limit and must be downloaded within 40 seconds.
failure_status_code
integer
A conventional HTTP status code: 401 - Authorization error with your API key or account 403 - Forbidden error with your API key or account 404 - The requested…
generated
object
7 properties
2 required
metadata
object
Use metadata to store custom information for tagging and labeling back to your internal systems. Must be an object with up to 20 key-value pairs. Keys must be…
country_extended
string
Must be a 2 letter country short-name code (ISO 3166). Does not accept US, AS, PR, FM, GU, MH, MP, PW, or VI. For these addresses, please use the US verificati…
return_address
Specifies the address the return envelope will be sent back to. This is an optional argument that is available if an account is signed up for the return envelo…
card_base
object
2 properties
ltr_id
string
Unique identifier prefixed with ltr.
buckslip_base
object
2 properties
failure_reason
object
An object describing the reason for failure if the resource failed to render.
3 properties
card_description
stringnull
Description of the card.
send_date
string
A timestamp in ISO 8601 format which specifies a date after the current time and up to 180 days in the future to send the letter off for production. Setting a…
address_fields_us
object
5 properties
4 required
billing_group_id
string
An optional string with the billing group ID to tag your usage with. Is used for billing purposes. Requires special activation to use. See Billing Group API fo…
address_placement
string
Specifies the location of the address information that will show through the double-window envelope. To see how this will impact your letter design, view our l…
failure_reason_error
object
Failure error details
7 properties
thumbnail
object
3 properties
date_filter
object
Filter by ISO-8601 date or datetime, e.g. { "gt": "2012-01-01", "lt": "2012-01-31T12:34:56Z" } where gt is , lt is <, gte is e, and lte is d.
merge_variables
objectnull
You can input a merge variable payload object to your template or QR code redirect URLs to render dynamic content. For example, if you have a template like: {{…
company
stringnull
Either name or company is required, you may also add both. Must be no longer than 40 characters. If both name and company are provided, they will be printed on…
list
object
Multiple items returned in order
5 properties
html_string
string
An HTML string of under 10,000 characters.
extra_service
stringnull
Add an extra service to your letter. Can only be non-null if mailtype isn't uspsstandard. See pricing for extra costs incurred. certified - track and confirm d…
double_sided
boolean
Set this attribute to true for double sided printing, or false for for single sided printing. Defaults to true.
adr_id
string
Unique identifier prefixed with adr.
tracking_event_base
object
As mail pieces travel through the mail stream, USPS scans their unique barcodes, and Lob processes these mail scans to generate tracking events.
5 properties
4 required
ltr_size
string
Specifies the size of the letter. It accepts two values usletter and uslegal. If the [Lob-Version header](tag/Versioning-and-Changelog) in the request is set t…
date_modified
string
A timestamp in ISO 8601 format of the date the resource was last modified.
return_envelope_user_provided
Indicates if a return envelope is requested for the letter. The value corresponding to this field is by default a boolean. But if the account is signed up for…
bo_id
string
Unique identifier prefixed with bo.
resource_description
stringnull
An internal description that identifies this resource. Must be no longer than 255 characters.
editable
object
5 properties
expected_delivery_date
string
A date in YYYY-MM-DD format of the mailpiece's expected delivery date based on its senddate.
count
integer
number of resources in a set
signed_link
string
A [signed link](section/Asset-URLs) served over HTTPS. The link returned will expire in 30 days to prevent mis-sharing. Each time a GET request is initiated, a…
tracking_event_details
object
4 properties
3 required
mail_type
string
A string designating the mail postage type: uspsfirstclass - (default) uspsstandard - a cheaper option which is less predictable and takes longer to deliver. u…
lob_base
object
4 properties
3 required
input_to
object
1 property
input_from
object
1 property
status
string
A string describing the PDF render status: processed - the rendering process is currently in progress. rendered - a PDF has been successfully rendered of the m…
campaign_id
stringnull
Denotes resources created by the provided campaign id, prefixed with cmp. In the case of snap packs, booklets, and letters with size uslegal, however, the camp…
date_created
string
A timestamp in ISO 8601 format of the date the resource was created.
color
boolean
Set this key to true if you would like to print in color. Set to false if you would like to print in black and white.
address_fields_intl
object
5 properties
2 required
deleted
boolean
Only returned if the resource has been successfully deleted.
The full machine-readable OpenAPI contract behind this narrative.
Other APIs Lob publishes across the network.
