NMI

NMI Webhook Events API

Here you can find information about webhook events

GitHub OpenAPI

Operations 8

POST /v5/payments/auth Authorization #
POST /v5/payments/credit Credit #
POST /v5/payments/sale Sale #
POST /v5/payments/validate Validate #
GET /v5/payments/{payment_id} Get #
POST /v5/payments/{payment_id}/capture Capture #
POST /v5/payments/{payment_id}/refund Refund #
POST /v5/payments/{payment_id}/void Void #

Documentation

📖
Documentation
https://docs.nmi.com/docs

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/openapi/nmi-payments-api-openapi.yml

Schemas & Data

📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-get-transaction-data-response-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-get-merchant-list-response-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-assign-fee-schedule-to-merchant-response-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-create-merchant-response-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-get-specific-merchant-information-response-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/json-schema/nmi-get-merchant-processors-and-value-added-services-details-response-schema.json

Other Resources

🔗
Sandbox
https://docs.nmi.com/docs/sandbox-testing

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for apis

7 MCP tools reach this
  • find_apisBrowse and filter every API in the catalog.
  • get_api_artifactsOne API's artifacts, grouped by type.
  • get_openapiThe primary OpenAPI for this API.
  • find_similar_apisAPIs that look like this one.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
This API 
curl "https://apis.io/api/v1/apis/nmi:nmi-payments-api"
All apis 
curl "https://apis.io/api/v1/apis?limit=25"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.

OpenAPI Specification

nmi-payments-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  version: 1.0.0
  title: Payments API
  description: Our payments platform exposes two generations of API.
  x-logo:
    url: https://www.nmi.com/app/themes/nmi/images/NMI_Logo_Primary.webp
servers:
- url: https://sandbox.nmi.com/api
security: []
tags:


# --- truncated at 32 KB (72 KB total) ---
# Full source: https://raw.githubusercontent.com/api-evangelist/nmi/refs/heads/main/openapi/nmi-payments-api-openapi.yml