Testmail

Testmail is an email testing API platform for developers and QA teams that provides programmable inboxes with unlimited email addresses via a namespace.tag routing scheme. It offers both a JSON REST API and a GraphQL API for instant, programmatic retrieval of test emails, supporting automated end-to-end email testing in development workflows and CI/CD pipelines. Key capabilities include wildcard tag searches, live queries, pagination, spam score testing via SpamAssassin, and attachment handling.

Testmail publishes 2 APIs on the APIs.io network: GraphQL API and Inbox API. Tagged areas include Email Testing, Developer Tools, API Testing, GraphQL, and REST API.

The Testmail catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Testmail’s developer surface includes authentication, documentation, engineering blog, pricing, and 9 more developer resources.

🌐 Visit website 📡 Source on GitHub

44.5/100 developing ▬ flat Agent 31/100 agent ready Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0

AccessFreemiumSelf serve⚡ Free to try

2 APIs

Email Testing Developer Tools API Testing GraphQL REST API CI/CD QA AutomationProgrammable Inboxes

Kin Score

Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0

Composite quality — 44.5/100 · developing

Contract Quality 17.0 / 25

Developer Ergonomics 4.8 / 20

Access Clarity 10.0 / 20

Operational Transparency 4.8 / 13

Contract Governance 1.2 / 12

Discoverability 6.9 / 10

Agent readiness — 31/100 · agent ready

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 8 / 8

Request/Response Examples 7 / 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 Surface 0 / 5

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/testmail-app: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 2

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

GraphQL 1

GraphQL schemas published by this provider.

Rate Limits 1

Documented rate limits and quota policies.

Testmail App Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

JSON Schema 3

Standalone JSON Schema definitions for this provider's data models.

Examples 4

Example request and response payloads for these APIs.

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrg

GitHubOrg

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

StatusPage

StatusPage

RateLimits

RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

Plans

Plans

FinOps

FinOps

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Source (apis.yml)

aid: testmail-app
name: Testmail
description: Testmail is an email testing API platform for developers and QA teams that provides programmable inboxes with
  unlimited email addresses via a namespace.tag routing scheme. It offers both a JSON REST API and a GraphQL API for instant,
  programmatic retrieval of test emails, supporting automated end-to-end email testing in development workflows and CI/CD
  pipelines. Key capabilities include wildcard tag searches, live queries, pagination, spam score testing via SpamAssassin,
  and attachment handling.
type: Index
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/testmail-app.png
url: https://raw.githubusercontent.com/api-evangelist/testmail-app/refs/heads/main/apis.yml
created: '2026-06-13'
modified: '2026-06-13'
specificationVersion: '0.23'
tags:
- Email Testing
- Developer Tools
- API Testing
- GraphQL
- REST API
- CI/CD
- QA Automation
- Programmable Inboxes
apis:
- aid: testmail-app:testmail-graphql-api
  name: Testmail GraphQL API
  description: Full-featured GraphQL API for querying test emails from Testmail programmable inboxes. Supports advanced filtering,
    custom sorting, field selection, live queries, pagination, and spam reports. Bearer token authentication via Authorization
    header.
  humanURL: https://testmail.app/docs/
  baseURL: https://api.testmail.app/api/graphql
  tags:
  - Email Testing
  - GraphQL
  properties:
  - type: Documentation
    url: https://testmail.app/docs/
  - type: GraphQLEndpoint
    url: https://api.testmail.app/api/graphql
  - type: OpenAPI
    url: openapi/testmail-app-graphql-api-openapi.yml
- aid: testmail-app:testmail-app-inbox-api
  name: Testmail Inbox API
  description: Retrieve test emails from programmable inboxes
  humanURL: https://testmail.app/docs/
  baseURL: https://api.testmail.app/api/json
  tags:
  - Inbox
  properties:
  - type: OpenAPI
    url: openapi/testmail-app-inbox-api-openapi.yml
  - type: Documentation
    url: https://testmail.app/docs/
  - type: GraphQL
    url: graphql/testmail-app-graphql.md
common:
- type: AgenticAccess
  url: agentic-access/testmail-app-agentic-access.yml
- type: DomainSecurity
  url: security/testmail-app-domain-security.yml
- type: Authentication
  url: authentication/testmail-app-authentication.yml
- type: Website
  url: https://testmail.app
- type: Documentation
  url: https://testmail.app/docs/
- type: GitHubOrg
  url: https://github.com/testmail-app
- type: X
  url: https://x.com/testmailapp
- type: Blog
  url: https://testmail.app/blog/
- type: Pricing
  url: https://testmail.app/pricing/
- type: StatusPage
  url: https://status.testmail.app
- type: Plans
  url: plans/testmail-app-plans-pricing.yml
- type: RateLimits
  url: rate-limits/testmail-app-rate-limits.yml
- type: FinOps
  url: finops/testmail-app-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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