Postmark

Postmark is an email delivery service that helps businesses send and track transactional and broadcast email reliably, replacing SMTP with a scalable service that surfaces detailed delivery analytics, bounce tracking, open and click tracking, and dedicated IP addresses.

Postmark publishes 30 APIs on the APIs.io network, including Activate API, Alias API, Batch API, and 27 more. Tagged areas include Emails, Messaging, Transactional Email, Deliverability, and SMTP.

The Postmark catalog on APIs.io includes 1 event-driven AsyncAPI specification and 2 Spectral governance rulesets.

Postmark’s developer surface includes documentation, getting-started guide, pricing, signup flow, engineering blog, support, changelog, and 57 more developer resources.

🌐 Visit website 📡 Source on GitHub

71.3/100 exemplar ▬ flat Agent 40/100 agent ready saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessFreemium

3 APIs 1 MCP Servers 6 Agent Skills 16 Features

Emails Messaging Transactional Email Deliverability SMTP Email API Webhookinbound emailEmail TemplatesEmail Analytics

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 71.3/100 · exemplar

Contract Quality 13.1 / 23

Developer Ergonomics 16.3 / 18

Access Clarity 14.9 / 18

Operational Transparency 9.5 / 12

Contract Governance 3.6 / 11

Discoverability 7.3 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 40/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/postmark: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 30

Individual APIs this provider publishes, each with its own machine-readable definition.

Postmark Activate API

The Activate API from Postmark — 1 operation(s) for activate.

Postmark Alias API

The Alias API from Postmark — 1 operation(s) for alias.

Postmark Batch API

The Batch API from Postmark — 2 operation(s) for batch.

Postmark Bounceid API

The Bounceid API from Postmark — 3 operation(s) for bounceid.

Postmark Bounces API API

The Bounces API API from Postmark — 5 operation(s) for bounces api.

Postmark Bounces API

The Bounces API from Postmark — 2 operation(s) for bounces.

Postmark Browser Families API

The Browser Families API from Postmark — 1 operation(s) for browser families.

Postmark Bypass API

The Bypass API from Postmark — 1 operation(s) for bypass.

Postmark Deliverystats API

The Deliverystats API from Postmark — 1 operation(s) for deliverystats.

Postmark Domains API API

The Domains API API from Postmark — 6 operation(s) for domains api.

Postmark Dump API

The Dump API from Postmark — 2 operation(s) for dump.

Postmark Email API

The Email API from Postmark — 4 operation(s) for email.

Postmark Emailclients API

The Emailclients API from Postmark — 1 operation(s) for emailclients.

Postmark Inbound API

The Inbound API from Postmark — 4 operation(s) for inbound.

Postmark Inbound Rules API API

The Inbound Rules API API from Postmark — 2 operation(s) for inbound rules api.

Postmark Locations API

The Locations API from Postmark — 1 operation(s) for locations.

Postmark Message Identifier API

The Message Identifier API from Postmark — 2 operation(s) for message identifier.

Postmark Messages API API

The Messages API API from Postmark — 11 operation(s) for messages api.

Postmark Messages API

The Messages API from Postmark — 11 operation(s) for messages.

Postmark Outbound API

The Outbound API from Postmark — 20 operation(s) for outbound.

Postmark Sender Signatures API API

The Sender Signatures API API from Postmark — 5 operation(s) for sender signatures api.

Postmark Sending API API

The Sending API API from Postmark — 4 operation(s) for sending api.

Postmark Server Configuration API API

The Server Configuration API API from Postmark — 1 operation(s) for server configuration api.

Postmark Server Management API API

The Server Management API API from Postmark — 2 operation(s) for server management api.

Postmark Servers API

The Servers API from Postmark — 1 operation(s) for servers.

Postmark Stats API API

The Stats API API from Postmark — 12 operation(s) for stats api.

Postmark Templates API API

The Templates API API from Postmark — 6 operation(s) for templates api.

Postmark Templates API

The Templates API from Postmark — 4 operation(s) for templates.

Postmark Triggerid API

The Triggerid API from Postmark — 1 operation(s) for triggerid.

Postmark Triggers API

The Triggers API from Postmark — 4 operation(s) for triggers.

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MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Postmark MCP Server

Postmark ships an official, first-party MCP server. It is distributed ONLY as a local-stdio npm package — there is no hosted remote endpoint an MCP client can POST to. Postmark'...

Pricing Plans 1

Published pricing tiers and plan structures.

Postmark Plans Pricing

4 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Postmark Rate Limits

11 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Postmark Finops

FINOPS

Features 16

Notable capabilities this provider offers.

Free: 100 emails/month

Basic: $15/mo for 10K emails

Pro: $16.50/mo for 10K emails with templates and webhooks

Platform: $18/mo for 10K emails with multiple servers and dedicated IPs

Email API and SMTP server

Templates with versioning (Pro+)

Webhooks for delivery, bounce, open, click, spam, subscription events

Bounce and spam complaint handling

Server tokens for per-environment isolation

Send up to 500 emails per batch request

Inbound email parsing

Message Streams (broadcast vs transactional)

OpenTracker beacon for opens/clicks

Suppression management

Dedicated IPs (Platform)

Best-in-class deliverability

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Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Postmark Webhooks

AsyncAPI description of Postmark's outbound webhook surface. Postmark delivers event notifications by issuing HTTP POST requests with a JSON body to a URL the customer configure...

ASYNCAPI

Spectral Rules 2

Spectral governance rulesets for linting and validating these APIs.

Postmark API Rules

8 rules · 1 errors 7 warnings

SPECTRAL

Postmark API Rules

5 rules · 4 warnings 1 info

SPECTRAL

3 properties

JSON SCHEMA

TemplatesPushResponse

2 properties

JSON SCHEMA

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JSON Structure 1

JSON Structure definitions describing this provider's data shapes.

Postmark Structure

0 properties

JSON STRUCTURE

Security Posture 3

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Postmark Authentication

3 schemes

SECURITY

Postmark Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Postmark Trust Center

SOC 2, SSAE 16 SOC 1 Type 2, PCI DSS Level 1, HIPAA, GDPR

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Postmark Agentic Access

108 operations · 42 acting

AGENTIC

Resources

Get Started 5

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Signup

Signup

Login

Sandbox

Sandbox

DeveloperPortal

DeveloperPortal

Documentation 3

Reference material describing how the API behaves

Documentation

Documentation

AsyncAPI

AsyncAPI

APIReference

APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgentSkills

MCPServer

LLMsTxt

AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conformance

ErrorCatalog

Lifecycle

Conventions

DataModel

Webhooks

Vocabulary

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Build 7

SDKs, sample code, and the tooling you integrate with

GitHub

Packages

SDKs

ToolCrosswalk

CLI

GitHubOrganization

GitHubOrganization

Postman

Postman

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Access & Security 4

Authentication, authorization, and security posture

DomainSecurity

Compliance

TrustCenter

Authentication

Operate 6

Status, limits, changes, and where to get help

Support

StatusPage

ChangeLog

Deprecation

ChangeLog

RateLimits

Commercial 5

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

FinOps

Company 4

The organization behind the API

Website

Website

Blog

Blog

Twitter

Twitter

LinkedIn

Other 18

Properties that don't map to a standard resource type

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Templates

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Source (apis.yml)

aid: postmark
name: Postmark
description: Postmark is an email delivery service that helps businesses send and track transactional and broadcast email
  reliably, replacing SMTP with a scalable service that surfaces detailed delivery analytics, bounce tracking, open and click
  tracking, and dedicated IP addresses.
type: Index
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/postmark.png
url: https://raw.githubusercontent.com/api-evangelist/postmark/refs/heads/main/apis.yml
tags:
- Emails
- Messaging
- Transactional Email
- Deliverability
- SMTP
- Email API
- Webhook
- inbound email
- Email Templates
- Email Analytics
tags_raw:
- Emails
- Messaging
- Transactional Email
- Deliverability
- SMTP
- Email API
- Webhooks
- Inbound Email
- Email Templates
- Email Analytics
created: '2024-04-14'
modified: '2026-08-13'
specificationVersion: '0.23'
apis:
- aid: postmark:postmark-activate-api
  name: Postmark Activate API
  description: The Activate API from Postmark — 1 operation(s) for activate.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Activate
  properties:
  - type: OpenAPI
    url: openapi/postmark-activate-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-activate-api-overlay.yaml
- aid: postmark:postmark-alias-api
  name: Postmark Alias API
  description: The Alias API from Postmark — 1 operation(s) for alias.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Alias
  properties:
  - type: OpenAPI
    url: openapi/postmark-alias-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-alias-api-overlay.yaml
- aid: postmark:postmark-batch-api
  name: Postmark Batch API
  description: The Batch API from Postmark — 2 operation(s) for batch.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Batch
  properties:
  - type: OpenAPI
    url: openapi/postmark-batch-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-batch-api-overlay.yaml
- aid: postmark:postmark-bounceid-api
  name: Postmark Bounceid API
  description: The Bounceid API from Postmark — 3 operation(s) for bounceid.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Bounceid
  properties:
  - type: OpenAPI
    url: openapi/postmark-bounceid-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-bounceid-api-overlay.yaml
- aid: postmark:postmark-bounces-api-api
  name: Postmark Bounces API API
  description: The Bounces API API from Postmark — 5 operation(s) for bounces api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Bounces API
  properties:
  - type: OpenAPI
    url: openapi/postmark-bounces-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-bounces-api-api-overlay.yaml
- aid: postmark:postmark-bounces-api
  name: Postmark Bounces API
  description: The Bounces API from Postmark — 2 operation(s) for bounces.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Bounces
  properties:
  - type: OpenAPI
    url: openapi/postmark-bounces-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-bounces-api-overlay.yaml
- aid: postmark:postmark-browser-families-api
  name: Postmark Browser Families API
  description: The Browser Families API from Postmark — 1 operation(s) for browser families.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Browser Families
  properties:
  - type: OpenAPI
    url: openapi/postmark-browser-families-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-browser-families-api-overlay.yaml
- aid: postmark:postmark-bypass-api
  name: Postmark Bypass API
  description: The Bypass API from Postmark — 1 operation(s) for bypass.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Bypass
  properties:
  - type: OpenAPI
    url: openapi/postmark-bypass-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-bypass-api-overlay.yaml
- aid: postmark:postmark-deliverystats-api
  name: Postmark Deliverystats API
  description: The Deliverystats API from Postmark — 1 operation(s) for deliverystats.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Deliverystats
  properties:
  - type: OpenAPI
    url: openapi/postmark-deliverystats-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-deliverystats-api-overlay.yaml
- aid: postmark:postmark-domains-api-api
  name: Postmark Domains API API
  description: The Domains API API from Postmark — 6 operation(s) for domains api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Domains API
  properties:
  - type: OpenAPI
    url: openapi/postmark-domains-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-domains-api-api-overlay.yaml
- aid: postmark:postmark-dump-api
  name: Postmark Dump API
  description: The Dump API from Postmark — 2 operation(s) for dump.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Dump
  properties:
  - type: OpenAPI
    url: openapi/postmark-dump-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-dump-api-overlay.yaml
- aid: postmark:postmark-email-api
  name: Postmark Email API
  description: The Email API from Postmark — 4 operation(s) for email.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Email
  properties:
  - type: OpenAPI
    url: openapi/postmark-email-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-email-api-overlay.yaml
- aid: postmark:postmark-emailclients-api
  name: Postmark Emailclients API
  description: The Emailclients API from Postmark — 1 operation(s) for emailclients.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Email Clients
  tags_raw:
  - Emailclients
  properties:
  - type: OpenAPI
    url: openapi/postmark-emailclients-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-emailclients-api-overlay.yaml
- aid: postmark:postmark-inbound-api
  name: Postmark Inbound API
  description: The Inbound API from Postmark — 4 operation(s) for inbound.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Inbound
  properties:
  - type: OpenAPI
    url: openapi/postmark-inbound-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-inbound-api-overlay.yaml
- aid: postmark:postmark-inbound-rules-api-api
  name: Postmark Inbound Rules API API
  description: The Inbound Rules API API from Postmark — 2 operation(s) for inbound rules api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Inbound Rules API
  properties:
  - type: OpenAPI
    url: openapi/postmark-inbound-rules-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-inbound-rules-api-api-overlay.yaml
- aid: postmark:postmark-locations-api
  name: Postmark Locations API
  description: The Locations API from Postmark — 1 operation(s) for locations.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Locations
  properties:
  - type: OpenAPI
    url: openapi/postmark-locations-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-locations-api-overlay.yaml
- aid: postmark:postmark-message-identifier-api
  name: Postmark Message Identifier API
  description: The Message Identifier API from Postmark — 2 operation(s) for message identifier.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Message Identifier
  properties:
  - type: OpenAPI
    url: openapi/postmark-message-identifier-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-message-identifier-api-overlay.yaml
- aid: postmark:postmark-messages-api-api
  name: Postmark Messages API API
  description: The Messages API API from Postmark — 11 operation(s) for messages api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Messages API
  properties:
  - type: OpenAPI
    url: openapi/postmark-messages-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-messages-api-api-overlay.yaml
- aid: postmark:postmark-messages-api
  name: Postmark Messages API
  description: The Messages API from Postmark — 11 operation(s) for messages.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Message
  tags_raw:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/postmark-messages-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-messages-api-overlay.yaml
- aid: postmark:postmark-outbound-api
  name: Postmark Outbound API
  description: The Outbound API from Postmark — 20 operation(s) for outbound.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Outbound
  properties:
  - type: OpenAPI
    url: openapi/postmark-outbound-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-outbound-api-overlay.yaml
- aid: postmark:postmark-sender-signatures-api-api
  name: Postmark Sender Signatures API API
  description: The Sender Signatures API API from Postmark — 5 operation(s) for sender signatures api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Sender Signatures API
  properties:
  - type: OpenAPI
    url: openapi/postmark-sender-signatures-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-sender-signatures-api-api-overlay.yaml
- aid: postmark:postmark-sending-api-api
  name: Postmark Sending API API
  description: The Sending API API from Postmark — 4 operation(s) for sending api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Sending API
  properties:
  - type: OpenAPI
    url: openapi/postmark-sending-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-sending-api-api-overlay.yaml
- aid: postmark:postmark-server-configuration-api-api
  name: Postmark Server Configuration API API
  description: The Server Configuration API API from Postmark — 1 operation(s) for server configuration api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Server Configuration API
  properties:
  - type: OpenAPI
    url: openapi/postmark-server-configuration-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-server-configuration-api-api-overlay.yaml
- aid: postmark:postmark-server-management-api-api
  name: Postmark Server Management API API
  description: The Server Management API API from Postmark — 2 operation(s) for server management api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Server Management API
  properties:
  - type: OpenAPI
    url: openapi/postmark-server-management-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-server-management-api-api-overlay.yaml
- aid: postmark:postmark-servers-api
  name: Postmark Servers API
  description: The Servers API from Postmark — 1 operation(s) for servers.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Servers
  properties:
  - type: OpenAPI
    url: openapi/postmark-servers-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-servers-api-overlay.yaml
- aid: postmark:postmark-stats-api-api
  name: Postmark Stats API API
  description: The Stats API API from Postmark — 12 operation(s) for stats api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Stats API
  properties:
  - type: OpenAPI
    url: openapi/postmark-stats-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-stats-api-api-overlay.yaml
- aid: postmark:postmark-templates-api-api
  name: Postmark Templates API API
  description: The Templates API API from Postmark — 6 operation(s) for templates api.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Templates API
  properties:
  - type: OpenAPI
    url: openapi/postmark-templates-api-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-templates-api-api-overlay.yaml
- aid: postmark:postmark-templates-api
  name: Postmark Templates API
  description: The Templates API from Postmark — 4 operation(s) for templates.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Templates
  properties:
  - type: OpenAPI
    url: openapi/postmark-templates-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-templates-api-overlay.yaml
- aid: postmark:postmark-triggerid-api
  name: Postmark Triggerid API
  description: The Triggerid API from Postmark — 1 operation(s) for triggerid.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Triggerid
  properties:
  - type: OpenAPI
    url: openapi/postmark-triggerid-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-triggerid-api-overlay.yaml
- aid: postmark:postmark-triggers-api
  name: Postmark Triggers API
  description: The Triggers API from Postmark — 4 operation(s) for triggers.
  humanURL: https://postmarkapp.com/developer
  baseURL: https://api.postmarkapp.com
  tags:
  - Triggers
  properties:
  - type: OpenAPI
    url: openapi/postmark-triggers-api-openapi.yml
  - type: Documentation
    url: https://postmarkapp.com/developer
  - type: GettingStarted
    url: https://postmarkapp.com/developer/api/overview
  - type: Authentication
    url: https://postmarkapp.com/developer/api/overview#authentication
  - type: AsyncAPI
    url: asyncapi/postmark-webhooks-asyncapi.yml
  - type: Overlay
    url: overlays/postmark-triggers-api-overlay.yaml
common:
- type: Overlay
  url: overlays/postmark-messages-inbound-messageid-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-messages-outbound-clicks-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-messages-outbound-messageid-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-messages-outbound-opens-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-platforms-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-readtimes-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-retry-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-sends-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-spam-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-statistics-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-stats-outbound-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-stats-outbound-clicks-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-stats-outbound-opens-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-template-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-triggers-inboundrules-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-triggers-tags-api-overlay.yaml
- type: Overlay
  url: overlays/postmark-validate-api-overlay.yaml
- type: AgenticAccess
  url: agentic-access/postmark-agentic-access.yml
- type: DomainSecurity
  url: security/postmark-domain-security.yml
- name: Agent Skills
  url: https://github.com/ActiveCampaign/postmark-skills
  type: AgentSkills
- type: Website
  url: https://postmarkapp.com
- type: Documentation
  url: https://postmarkapp.com/developer
- type: GettingStarted
  url: https://postmarkapp.com/developer/api/overview
- type: Pricing
  url: https://postmarkapp.com/pricing
- type: Signup
  url: https://account.postmarkapp.com/sign_up
- type: Login
  url: https://account.postmarkapp.com/login
- type: Blog
  url: https://postmarkapp.com/blog
- type: Support
  url: https://postmarkapp.com/support
- type: StatusPage
  url: https://status.postmarkapp.com
- type: Templates
  url: https://postmarkapp.com/transactional-email-templates
- type: ChangeLog
  url: https://postmarkapp.com/updates
- type: TermsOfService
  url: https://postmarkapp.com/terms-of-service
- type: PrivacyPolicy
  url: https://wildbit.com/privacy
- type: GitHub
  url: https://github.com/ActiveCampaign
- type: Twitter
  url: https://twitter.com/postmarkapp
- type: LinkedIn
  url: https://www.linkedin.com/company/postmarkapp
- type: Features
  data:
  - 'Free: 100 emails/month'
  - 'Basic: $15/mo for 10K emails'
  - 'Pro: $16.50/mo for 10K emails with templates and webhooks'
  - 'Platform: $18/mo for 10K emails with multiple servers and dedicated IPs'
  - Email API and SMTP server
  - Templates with versioning (Pro+)
  - Webhooks for delivery, bounce, open, click, spam, subscription events
  - Bounce and spam complaint handling
  - Server tokens for per-environment isolation
  - Send up to 500 emails per batch request
  - Inbound email parsing
  - Message Streams (broadcast vs transactional)
  - OpenTracker beacon for opens/clicks
  - Suppression management
  - Dedicated IPs (Platform)
  - Best-in-class deliverability
  sources:
  - https://postmarkapp.com/pricing
  updated: '2026-05-04'
- type: Packages
  url: packages/postmark-packages.yml
- type: SDKs
  url: packages/postmark-packages.yml
- type: MCPServer
  url: mcp/postmark-mcp.yml
- type: ToolCrosswalk
  url: mcp/postmark-tool-crosswalk.yml
- type: LLMsTxt
  url: llms/postmark-llms.txt
- type: Conformance
  url: conformance/postmark-conformance.yml
- type: Compliance
  url: security/postmark-trust-center.yml
- type: TrustCenter
  url: security/postmark-trust-center.yml
- type: ErrorCatalog
  url: errors/postmark-problem-types.yml
- type: Lifecycle
  url: lifecycle/postmark-lifecycle.yml
- type: Deprecation
  url: lifecycle/postmark-lifecycle.yml
- type: Authentication
  url: authentication/postmark-authentication.yml
- type: Conventions
  url: conventions/postmark-conventions.yml
- type: ChangeLog
  url: changelog/postmark-changelog.yml
- type: CLI
  url: cli/postmark-cli.yml
- type: DataModel
  url: data-model/postmark-data-model.yml
- type: Sandbox
  url: sandbox/postmark-sandbox.yml
- type: Plans
  url: plans/postmark-plans-pricing.yml
- type: RateLimits
  url: rate-limits/postmark-rate-limits.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Webhooks
  url: asyncapi/postmark-webhooks-asyncapi.yml
- type: AsyncAPI
  url: asyncapi/postmark-webhooks-asyncapi.yml
- type: FinOps
  url: finops/postmark-finops.yml
- type: Vocabulary
  url: vocabulary/postmark-vocabulary.yml
- type: DeveloperPortal
  url: https://postmarkapp.com/developer
- type: APIReference
  url: https://postmarkapp.com/developer/api/overview
- type: GitHubOrganization
  url: https://github.com/ActiveCampaign
- type: Postman
  url: https://god.gw.postman.com/run-collection/15802082-f50b3ffc-9eee-4ab1-bdc5-8b423d19d535?action=collection%2Ffork&source=rip_markdown&collection-url=entityId%3D15802082-f50b3ffc-9eee-4ab1-bdc5-8b423d19d535%26entityType%3Dcollection%26workspaceId%3D55e9c6f2-5d69-40a5-b00b-caec1640454c
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 63
  pass: local-v1

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