Mailtrap

Mailtrap provides a RESTful email infrastructure API with high deliverability rates, an email sandbox for safe testing, and actionable analytics. It offers SDKs for smooth integration and supports both transactional sending and bulk email delivery.

Mailtrap publishes 3 API contracts indexed on the APIs.io network: Inboxes API, Messages API, and Send API. Tagged areas include Email, Email Delivery, Email Sandbox, Email Testing, and Transactional Email.

The Mailtrap catalog on APIs.io includes 1 Spectral governance ruleset.

Mailtrap’s developer surface includes authentication, developer portal, documentation, signup flow, pricing, support, engineering blog, and 15 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

37.8/100 thin ▬ flat Agent 21/100 agent aware Front door AI 6/6 dominant saas Full breakdown ↓
scored 2026-10-23 · rubric v0.25.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

2 published contracts

Email Email DeliveryEmail SandboxEmail Testing Transactional Email

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Software Product Engineering Management

BC-4200

Messages

GET /api/accounts/{account_id}/inboxes/{inbox_id}/messages GET /api/accounts/{account_id}/inboxes/{inbox_id}/messages/{message_id}/spam_report GET /api/accounts/{account_id}/inboxes/{inbox_id}/messages/{message_id}/analyze

Kin Score

Kin Score How this is scored →
scored 2026-10-23 · rubric v0.25.0

Composite quality — 37.8/100 · thin

Contract Quality 9.0 / 19

Developer Ergonomics 7.9 / 15

Access Clarity 3.8 / 15

Operational Transparency 1.8 / 10

Contract Governance 1.4 / 9

Discoverability 5.5 / 8

Regulatory Posture 1.8 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 21/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 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

Pagination 5 / 5

Distinct Operations 3 / 3

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

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.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

Show this score on your site.

It updates itself when the score changes. Paste this where you link to your API docs:

<a href="https://apis.io/providers/mailtrap/"><img src="https://apis.io/badge/mailtrap/card.svg" alt="Mailtrap on APIs.io — Kin Score by API Evangelist"></a>

Other styles, a README pill and a shields.io endpoint are on the badge page.

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/mailtrap: 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 →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Agent Skills (SKILL.md packages)	undeclared	-	1	1
Raycast Store Extensions (first-party publishers + community-wrapped products)	undeclared	-	1	1

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

APIs 3

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

Mailtrap Inboxes API

Manage sandbox inboxes

Mailtrap Messages API

Inspect captured messages

Mailtrap Send API

Send transactional and bulk emails

Open Collections 5

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Mailtrap Email Sending API

OPEN COLLECTION

Mailtrap Email Sandbox API

OPEN COLLECTION

Mailtrap Email Sending Inboxes API

OPEN COLLECTION

Mailtrap Email Sending Inboxes Messages API

OPEN COLLECTION

Mailtrap Email Sending Inboxes Send API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Mailtrap Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Mailtrap Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Mailtrap Finops

FINOPS

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Mailtrap — mailtrap openapi rules

0 rules ·

SPECTRAL

Security Posture 2

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

Mailtrap Authentication

apiKey/http · 2 schemes

SECURITY

Mailtrap Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

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

Mailtrap Agentic Access

23 operations · 12 acting · 1 human-in-the-loop

23 operations · 12 acting

AGENTIC

Resources

Get Started 3

Portal, sign-up, and the first successful call

Portal

Portal

Signup

Signup

Login

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LlmsText

LlmsText

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

SpectralRules

SpectralRules

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 3

Status, limits, changes, and where to get help

RateLimits

RateLimits

StatusPage

StatusPage

Support

Support

Commercial 5

Pricing, plans, and the legal terms of use

Plans

FinOps

Pricing

TermsOfService

PrivacyPolicy

Company 3

The organization behind the API

Website

Website

LinkedIn

Blog

Blog

Other 1

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: mailtrap
name: Mailtrap
description: Mailtrap provides a RESTful email infrastructure API with high deliverability rates, an email sandbox for safe
  testing, and actionable analytics. It offers SDKs for smooth integration and supports both transactional sending and bulk
  email delivery.
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: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/mailtrap.png
x-docs-platform: gitbook
x-docs-platform-confidence: high
x-docs-platform-checked: 2026-10-03
tags:
- Email
- Email Delivery
- Email Sandbox
- Email Testing
- Transactional Email
url: https://raw.githubusercontent.com/api-evangelist/mailtrap/refs/heads/main/apis.yml
created: '2025-02-06'
modified: '2026-09-16'
specificationVersion: '0.23'
apis:
- aid: mailtrap:mailtrap-inboxes-api
  name: Mailtrap Inboxes API
  description: Manage sandbox inboxes
  humanURL: https://mailtrap.io/email-api/
  baseURL: https://send.api.mailtrap.io
  tags:
  - Inboxes
  properties:
  - type: OpenAPI
    url: openapi/mailtrap-inboxes-api-openapi.yml
  - type: Documentation
    url: https://docs.mailtrap.io/developers
  - type: Reference
    url: https://api-docs.mailtrap.io/
  - type: GettingStarted
    url: https://docs.mailtrap.io/docs/sending-emails-overview
  - type: Documentation
    url: https://docs.mailtrap.io/docs/email-sandbox-overview
- aid: mailtrap:mailtrap-messages-api
  name: Mailtrap Messages API
  description: Inspect captured messages
  humanURL: https://mailtrap.io/email-api/
  baseURL: https://send.api.mailtrap.io
  tags:
  - Message
  tags_raw:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/mailtrap-messages-api-openapi.yml
  - type: Documentation
    url: https://docs.mailtrap.io/developers
  - type: Reference
    url: https://api-docs.mailtrap.io/
  - type: GettingStarted
    url: https://docs.mailtrap.io/docs/sending-emails-overview
  - type: Documentation
    url: https://docs.mailtrap.io/docs/email-sandbox-overview
- aid: mailtrap:mailtrap-send-api
  name: Mailtrap Send API
  description: Send transactional and bulk emails
  humanURL: https://mailtrap.io/email-api/
  baseURL: https://send.api.mailtrap.io
  tags:
  - Send
  properties:
  - type: OpenAPI
    url: openapi/mailtrap-send-api-openapi.yml
  - type: Documentation
    url: https://docs.mailtrap.io/developers
  - type: Reference
    url: https://api-docs.mailtrap.io/
  - type: GettingStarted
    url: https://docs.mailtrap.io/docs/sending-emails-overview
  - type: Documentation
    url: https://docs.mailtrap.io/docs/email-sandbox-overview
common:
- type: Plans
  url: plans/mailtrap-plans-pricing.yml
- type: RateLimits
  url: rate-limits/mailtrap-rate-limits.yml
- type: FinOps
  url: finops/mailtrap-finops.yml
- type: CapabilityMap
  url: capabilities/mailtrap-capability-edges.yml
  name: Mailtrap Business Capability Map
- type: Website
  url: https://mailtrap.io
- type: AgenticAccess
  url: agentic-access/mailtrap-agentic-access.yml
- type: DomainSecurity
  url: security/mailtrap-domain-security.yml
- type: Authentication
  url: authentication/mailtrap-authentication.yml
- type: GitHubOrganization
  url: https://github.com/mailtrap
- type: LinkedIn
  url: https://www.linkedin.com/company/mailtrap
- type: Portal
  url: https://mailtrap.io/
- type: Documentation
  url: https://docs.mailtrap.io/
- type: Signup
  url: https://mailtrap.io/register/signup
- type: Login
  url: https://mailtrap.io/users/sign_in
- type: Pricing
  url: https://mailtrap.io/pricing/
- type: StatusPage
  url: https://status.mailtrap.io/
- type: Support
  url: https://help.mailtrap.io/
- type: TermsOfService
  url: https://mailtrap.io/terms-of-use/
- type: PrivacyPolicy
  url: https://mailtrap.io/privacy-policy/
- type: LlmsText
  url: https://docs.mailtrap.io/llms.txt
- type: Blog
  url: https://mailtrap.io/blog/feed/
- type: SpectralRules
  url: https://github.com/mailtrap/mailtrap-openapi/blob/4e2f059c72ebaeb85202188ca7f361e02d0341ad/.spectral.yaml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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