Stannp provides a direct mail API enabling users to send postcards and letters programmatically.
Stannp provides a direct mail API enabling users to send postcards and letters programmatically. On Nagent, Stannp is exposed as a fully-configurable marketing automation integration that any agent can call — 32 actions, and API key authentication. No code is required to wire Stannp into your workflow — connect it once via the External Integrations panel and reuse it across every agent you build.
Agent builders use Stannp to automate the kinds of tasks marketing automation teams previously handled manually. Concrete examples — each one is a single agent step in Nagent — include:
Every action and trigger is paired with a structured input/output schema (visible in the sections below), so when you wire Stannp into Helix — our agentic agent builder — the editor knows exactly what each step expects and produces. Configure once, deploy anywhere across your Nagent agents.
Every operation an agent can call against Stannp, with input parameters and output schema. Drop these into any step of an agent built in Helix.
STANNP_ADD_RECIPIENTS_TO_GROUPTool to add existing recipients to a mailing list group. Use when you need to add recipients from your account to an existing group for campaign management.
Input parameters
ID of the group to add recipients to.
Comma-separated list of recipient IDs to add to the group (e.g., '1,2' or '45112,45113').
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_ADD_RECIPIENT_TO_GROUPTool to add a recipient to a recipient group. Use when you need to add new mailing list subscribers.
Input parameters
Recipient city.
Recipient email address.
Recipient company name.
Recipient country code; defaults to 'GB'.
Custom field 1.
Custom field 2.
Custom field 3.
First line of recipient address.
Second line of recipient address.
Third line of recipient address.
The ID of the recipient group to add the recipient to.
Recipient postcode.
Recipient last name.
Recipient first name.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CANCEL_POSTCARDTool to cancel a postcard if processing has not started yet. Use when you need to cancel a scheduled postcard before it enters production.
Input parameters
The ID of the postcard to cancel.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_CAMPAIGNTool to create a new direct mail campaign on the platform. Use when you need to set up a campaign with recipients and design templates. Requires a valid group_id with recipients.
Input parameters
A PDF or JPG file for the back image.
A PDF file URL or binary for the design artwork.
Name your campaign for reference.
Save the uploaded file as a new design template.
Required when using file or front/back. Example: A4, A5, A6.
The type of campaign: a6-postcard, a5-postcard, or letter.
A PDF or JPG file for the front image.
Addon code if available.
A group ID for the recipients.
A template ID to copy. If left out, a blank template will be used.
Filter for what recipients to include in the campaign.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_CAMPAIGN_SAMPLETool to produce a PDF sample of your campaign. The generated link will be valid for 30 minutes. Use when you need to preview a campaign before sending it to recipients.
Input parameters
ID of the campaign to produce a sample for.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_FOLDERTool to create a folder in your secure file transfer area. Use when you need to organize files or prepare a storage location before uploading documents.
Input parameters
The name of the folder you wish to create.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_GROUPTool to create a new recipient group in Stannp. Use when you need to organize contacts into a distinct group before sending campaigns.
Input parameters
Name of the group (must be unique within your account).
Optional description for the group.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_LETTERTool to create a letter with mail merge to insert address and variable data. Use when you need to send physical mail via Stannp API.
Input parameters
URL to a PDF/DOC file or base64-encoded file content. Maximum of 10 pages. Use this as alternative to template parameter.
Comma-separated tags for reference, searchable in reporting
If true, produces a sample PDF without dispatching or charging. Defaults to false.
Addon codes to upgrade your letter (e.g., FIRST_CLASS for first-class postage)
Set to false to print only on the front of each page. Defaults to true.
ID of a template already set up on the platform
If true, overlay clear zones with white background. Defaults to true.
ID of an existing recipient in your account. Use this OR recipient_details, not both.
If false, the item will not be posted if the recipient address cannot be verified. Defaults to true.
Detailed recipient information for creating a new recipient.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_POSTCARDTool to create a postcard. Use when you need to send a postcard via direct mail.
Input parameters
URL or path to back image (JPG or PDF)
Postcard size: "4x6", "6x9", or "6x11"
Tags for tracking and reporting
Test mode - generates PDF but doesn't dispatch
URL or path to front image (JPG or PDF)
Message text to include on the postcard
Recipient information including firstname, lastname, address1, city, zipcode, country
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_CREATE_SELECTIONTool to create a new recipient selection for targeting in Stannp. Use when you need to create an auto filter selection to target specific recipients within a group based on criteria.
Input parameters
Optional name for the filter selection to help identify it.
Specially formatted filter string: \[column_name\]:::\[operator\]:::\[value\]. Valid operators: matches, contains, begins, ends, before, after, less_than, more_than, is_not. Chain multiple filters with :::AND:::. Example: 'firstname:::contains:::test' or 'firstname:::contains:::john:::AND:::age:::more_than:::25'.
The ID of the group to associate this selection with.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_DELETE_GROUPTool to delete a recipient group in Stannp. Recipients remain on your account unless delete_recipients is true. Use when you need to remove a mailing list group.
Input parameters
ID of the group to delete.
If true, completely delete all recipients in the group. Defaults to false (recipients remain on your account).
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_DELETE_RECIPIENTTool to permanently delete a recipient from your account. Use when you need to remove a recipient from your mailing list.
Input parameters
ID of the recipient to delete.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_ACCOUNT_BALANCETool to retrieve the current account balance. Use when you need to check available account funds.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_CAMPAIGNTool to retrieve details of a specific campaign. Use when you need to get information about a campaign by its ID.
Input parameters
ID of the campaign to retrieve
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_CAMPAIGN_AVAILABLE_DATESTool to get available dates for scheduling a campaign (up to 30 days). Use when you need to check which dates are available for campaign dispatch.
Input parameters
End date in YYYY-MM-DD format for the date range query.
Start date in YYYY-MM-DD format for the date range query.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_CAMPAIGN_COSTTool to get the estimated cost of booking a campaign. Use when you need to calculate the total cost before booking a direct mail campaign.
Input parameters
ID of the campaign to get the cost of booking.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_CONTACTTool to retrieve details of a specific contact. Use when you need all stored fields of a contact by its ID.
Input parameters
The ID of the contact to retrieve
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_CURRENT_USERTool to get information about the currently authenticated user including rate limit status. Use when you need to retrieve the current user's account details or check API rate limit status.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_GET_REPORTING_SUMMARYTool to get a status summary on individual items within a date range. Use when you need reporting metrics for mailpieces including delivery status, printing status, and counts.
Input parameters
End date in YYYY-MM-DD format for the reporting period
Start date in YYYY-MM-DD format for the reporting period
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_IMPORT_RECIPIENTSTool to import recipients from a CSV or XLS file into a Stannp recipient group. Use when you have a mailing list file ready to upload.
Input parameters
Base64-encoded CSV or XLS file content to upload
ID of the recipient group to import into
Whether to update existing recipients if duplicates are found
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_CAMPAIGNSTool to get a list of all campaigns. Use when you need to retrieve campaigns after authentication.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_CONTACTSTool to list all contacts. Use when you need to retrieve contacts with optional pagination filters.
Input parameters
Page number for paginated results
Number of results per page
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_FOLDERSTool to get a list of folders in your secure file transfer area. Use when you need to retrieve available folders for file organization.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_GROUPSTool to get a list of mailing groups on your account. Use when you need to retrieve all groups with optional pagination.
Input parameters
Limit for pagination. Specifies the maximum number of groups to return.
Offset for pagination. Specifies the starting point for the result set.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_MAILPIECESTool to retrieve mailpiece objects sent within a date range. Use when you need to query mailing history with optional status or tag filters.
Input parameters
Filter by custom tag associated with mailpieces
Filter by delivery status (e.g., delivered, returned, printing, local_delivery)
End date of the reporting period in YYYY-MM-DD format
Start date of the reporting period in YYYY-MM-DD format
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_LIST_TEMPLATESTool to list all templates associated with the account. Use when you need to retrieve available templates after authentication.
Input parameters
Page number for paginated results
Number of records per page
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_MERGE_PDFSTool to merge multiple PDF files into a single file. Use when you need to consolidate multiple PDFs into one document.
Input parameters
An array of URLs for the PDF files to merge. Provide at least 2 URLs to merge.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_PURGE_GROUPTool to remove all recipients from a mailing list. Recipients remain on your account if delete_recipients is false.
Input parameters
ID of the group to purge.
If true, completely delete all recipients. Defaults to false.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_RECALCULATE_GROUPTool to recalculate a group to ensure stats are up to date. Use when you need to refresh group statistics after adding or removing recipients.
Input parameters
The ID of the group to recalculate.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_REMOVE_RECIPIENTS_FROM_GROUPTool to remove recipients from a group without deleting them. Use when you need to remove contacts from a mailing group while keeping them in your account.
Input parameters
ID of the group to remove recipients from.
Comma-separated recipient IDs to remove from the group.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_UPLOAD_FILETool to upload a file to your secure file transfer area. Use when you need to upload files for direct mail campaigns. Supports both URL-based imports and binary file uploads.
Input parameters
File to upload. Can be either a file or a URL string pointing to a remote file to be imported (e.g., 'https://example.com/file.pdf').
A folder ID for placing the file in a specific folder
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
STANNP_VALIDATE_ADDRESSTool to validate a postal address. Currently supports UK and US addresses only. Use when you need to verify if a given address is valid before sending mail.
Input parameters
Address city.
Two-letter state abbreviation if possible.
Company name.
ISO 3166-1 Alpha 2 Country Code (US, GB, CA, FR...).
Address zipcode.
Address line 1.
Address line 2.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
No publicly available marketplace agent is found using this tool yet. There are 96 agents privately built on Nagent that already use Stannp.
Build on Nagent
Connect Stannp to any Nagent agent in minutes — no API key management, no boilerplate. Just configure and deploy.
The five questions agent builders ask before adopting a new integration.
Open the External Integrations panel inside Nagent (app.nagent.ai/externalIntegration), find Stannp, and click "Connect Now." You'll authenticate with an API key — Nagent handles credential storage and refresh automatically. Once connected, Stannp is available to any agent in your workspace.
No. Nagent provides no-code integration for every tool. Once Stannp is connected, you configure its 32 actions directly in the agent builder UI — no API calls, no boilerplate, no schema management.
Helix — Nagent's agentic agent builder — lets you drop Stannp steps into any workflow visually. Pick an action (e.g., one of those listed above), fill in the inputs (Helix knows the required vs. optional schema for each parameter), and connect it to upstream/downstream steps. Triggers run as the entry point of an agent, so when a Stannp event fires, the agent kicks off automatically.
Every Stannp action and trigger ships with a fully-typed schema — input parameters with name, type, required flag, and description, plus the output payload shape. The schemas are documented in the sections above. Helix uses these schemas to validate your configuration at build time and to type-check the data flowing between steps.
Yes. While Stannp ships with 32 pre-built marketing automation actions, you can layer custom logic around them inside Helix — pre/post-processing steps, conditional branches, retries, or stitching Stannp together with other connected tools. For deeper customization, talk to our team about Nagent's Agentic AI Lab — forward-deployed engineers who build Stannp-based workflows tailored to your business.