mails-ai

Mails.ai provides a self‑serve AI email API designed for artificial‑intelligence agents. It offers programmatic email addresses with built‑in parsing, identity verification, and reputation scoring, enabling agents to send, receive, and process emails as a core primitive. The platform includes free tier access, scalable pricing, and features like structured reply events and prompt‑injection scanning, targeting developers building AI‑driven communication workflows.

mails-ai publishes 19 API contracts indexed on the APIs.io network, including Account API, Agents API, API Keys API, and 16 more. Tagged areas include Company, AI, Email, Infrastructure, and Agents.

The mails-ai catalog on APIs.io includes 1 event-driven AsyncAPI specification, 1 JSON-LD context, and 1 Spectral governance ruleset.

mails-ai’s developer surface includes sandbox, authentication, pricing, changelog, engineering blog, API reference, getting-started guide, and 32 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

64.4/100 strong Agent 65/100 agent native Full breakdown ↓
scored 2026-10-31 · rubric v0.25.0 · Show this score on your site →

1 published contract 1 MCP Servers 4 Agent Skills

CompanyAIEmail Infrastructure Agents

Kin Score

Kin Score How this is scored →
scored 2026-10-31 · rubric v0.25.0

Composite quality — 64.4/100 · strong

Contract Quality 14.4 / 21

Developer Ergonomics 11.6 / 17

Access Clarity 15.7 / 17

Operational Transparency 3.8 / 11

Contract Governance 2.2 / 10

Discoverability 4.8 / 9

Regulatory Posture 4.9 / 15

Agent readiness — 65/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 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 4 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 5 / 5

Registration Without a Human 6 / 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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too
Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's
Dry-Run / Simulate Mode +4 pts — OpenAPI: destructive operations expose a dry_run / simulate / preview / validate_only parameter
Consent & Bot Identity +3 pts — common[].type includes AIPREF, ContentSignal, WebBotAuth, or HTTPMessageSignatures

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Governance scores 22.0 — up to +9.4 composite points
Operational Transparency scores 34.2 — up to +8.6 composite points
Contract Quality scores 67.7 — up to +8.1 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

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 the provider profile at artifacts.apis.io/mails-ai/apis.yml: open an issue on github.com/api-evangelist/mails-ai to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 19

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

mails-ai Account API

Identify the current API key.

mails-ai Agents API

Per-agent email identities and their sending policy.

mails-ai API Keys API

Create, list, and revoke API keys.

mails-ai Billing API

Usage metering and the Stripe billing portal.

mails-ai Connected Apps API

The apps connected by signing in (the mails CLI, Claude, ChatGPT …): list and revoke them.

mails-ai Domains API

Bring-your-own custom sending domains (records-only DNS verification).

mails-ai Drafts API

Compose, edit, schedule, and send drafts.

mails-ai Events API

Typed events (incl. classifier output) and the SSE live stream.

mails-ai Inbound API

Received messages and the test-key inbound simulator.

mails-ai Labels API

Label objects: a name and a colour, applied to threads.

mails-ai Logs API

Audit trail of state-changing operations.

mails-ai Messages API

Send, list, retrieve, reply, forward, schedule, and cancel email.

mails-ai Metrics API

Sent, delivered, bounced, complained, received and reply counts over time.

mails-ai Public API

Unauthenticated endpoints (health, unsubscribe link targets).

mails-ai Reputation API

Workspace- and agent-level deliverability reputation.

mails-ai Search API

Full-text search over received and sent mail.

mails-ai Suppression API

Suppression lookups and the consent allowlist.

mails-ai Threads API

Conversation threads grouping inbound + outbound messages, with read state, folders and labels.

mails-ai Webhooks API

Endpoint registration, delivery history, test, and replay.

Scroll for all 19

MCP Servers 1

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

mails-ai MCP Server

Remote MCP server at help.mails.ai.

MCP SERVER

Agent Skills 4

Packaged agent skills for driving this provider's APIs from an AI assistant.

mails-ai-create-and-retrieve-label

AGENT SKILL

mails-ai-create-and-send-draft

AGENT SKILL

mails-ai-manage-webhook

AGENT SKILL

mails-ai-simulate-and-retrieve

AGENT SKILL

Pricing Plans 1

Published pricing tiers and plan structures.

Mails Ai Plans Pricing

3 plans

PLANS

Event Specifications 1

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

Mails Ai Webhooks

ASYNCAPI

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Mails Ai Context

58 classes · 202 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

mails-ai API Rules

16 rules · 12 errors 3 warnings 1 info

SPECTRAL

Security Posture 4

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

Mails Ai Authentication

1 scheme

SECURITY

Mails Ai Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Mails Ai Vulnerability Disclosure

security.txt · contact published

SECURITY

Mails Ai Trust Center

SOC 2, ISO 27001, HIPAA, GDPR

SECURITY

Agentic Access 1

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

Mails Ai Agentic Access

74 operations · 38 acting · 3 human-in-the-loop

74 operations · 38 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

Sandbox

Sandbox

Login

GettingStarted

GettingStarted

DeveloperPortal

DeveloperPortal

Documentation 2

Reference material describing how the API behaves

APIReference

APIReference

Documentation

Documentation

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgentSkill

LLMsTxt

MCPServer

WellKnown

Design & Contract 10

Pagination, idempotency, versioning, errors, and events

Spectral

JSONLD

Vocabulary

Webhooks

DataModel

Idempotency

Conventions

ErrorCatalog

Conformance

Webhooks

Scroll for all 10

Build 2

SDKs, sample code, and the tooling you integrate with

Packages

Packages

SDKs

SDKs

Access & Security 7

Authentication, authorization, and security posture

Compliance

Authentication

SecurityTxt

Security

TrustCenter

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Scroll for all 7

Operate 1

Status, limits, changes, and where to get help

ChangeLog

ChangeLog

Commercial 4

Pricing, plans, and the legal terms of use

Plans

TermsOfService

PrivacyPolicy

Pricing

Company 2

The organization behind the API

Blog

Blog

Website

Website

Other 2

Properties that don't map to a standard resource type

Vendors

Vendors

Hosts

Hosts

Source (apis.yml)

aid: mails-ai
name: mails-ai
image: https://mails.ai/opengraph-image?0a8355ca24bf13de
description: Mails.ai provides a self‑serve AI email API designed for artificial‑intelligence agents. It offers programmatic
  email addresses with built‑in parsing, identity verification, and reputation scoring, enabling agents to send, receive,
  and process emails as a core primitive. The platform includes free tier access, scalable pricing, and features like structured
  reply events and prompt‑injection scanning, targeting developers building AI‑driven communication workflows.
url: https://artifacts.apis.io/mails-ai/apis.yml
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-10-31 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-10-30'
modified: '2026-10-30'
tags:
- Company
- AI
- Email
- Infrastructure
- Agents
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Vendors
  url: vendors/mails-ai-vendors.yml
- type: AgenticAccess
  url: agentic-access/mails-ai-agentic-access.yml
- type: Plans
  url: plans/mails-ai-plans-pricing.yml
- type: Spectral
  url: rules/mails-ai-rules.yml
- type: JSONLD
  url: json-ld/mails-ai-context.jsonld
- type: Vocabulary
  url: vocabulary/mails-ai-vocabulary.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Webhooks
  url: asyncapi/mails-ai-webhooks.yml
- type: DataModel
  url: data-model/mails-ai-data-model.yml
- type: Idempotency
  url: conventions/mails-ai-conventions.yml
- type: Conventions
  url: conventions/mails-ai-conventions.yml
- type: Sandbox
  url: sandbox/mails-ai-sandbox.yml
- type: Compliance
  url: https://mails.ai/trust
- type: Authentication
  url: authentication/mails-ai-authentication.yml
- type: ErrorCatalog
  url: errors/mails-ai-problem-types.yml
- type: Conformance
  url: conformance/mails-ai-conformance.yml
- type: LLMsTxt
  url: llms/mails-ai-llms.txt
- type: MCPServer
  url: mcp/mails-ai-mcp.yml
- type: SecurityTxt
  url: well-known/mails-ai-security.txt
- type: WellKnown
  url: well-known/mails-ai-well-known.yml
- type: Hosts
  url: hosts/mails-ai-hosts.yml
- type: Packages
  url: packages/mails-ai-packages.yml
- type: Webhooks
  url: https://mails.ai/features/webhooks
- type: TermsOfService
  url: https://mails.ai/terms
- type: Security
  url: https://mails.ai/security
- type: SDKs
  url: https://www.npmjs.com/package/@mailsai/sdk
- type: PrivacyPolicy
  url: https://mails.ai/privacy
- type: Pricing
  url: https://mails.ai/pricing
- type: Login
  url: https://app.mails.ai/signin
- type: ChangeLog
  url: https://mails.ai/changelog
- type: Blog
  url: https://mails.ai/blog
- type: APIReference
  url: https://mails.ai/docs/api-reference
- type: GettingStarted
  url: https://mails.ai/docs/quickstart
- type: Documentation
  url: https://help.mails.ai/
- type: DeveloperPortal
  url: https://api.mails.ai</code
- type: TrustCenter
  url: security/mails-ai-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/mails-ai-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/mails-ai-domain-security.yml
- type: Website
  url: https://mails.ai/
apis:
- aid: mails-ai:mails-ai-account-api
  name: mails-ai Account API
  description: Identify the current API key.
  baseURL: https://api.mails.ai
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-account-api-openapi.yml
- aid: mails-ai:mails-ai-agents-api
  name: mails-ai Agents API
  description: Per-agent email identities and their sending policy.
  baseURL: https://api.mails.ai
  tags:
  - Agents
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-agents-api-openapi.yml
- aid: mails-ai:mails-ai-api-keys-api
  name: mails-ai API Keys API
  description: Create, list, and revoke API keys.
  baseURL: https://api.mails.ai
  tags:
  - API Keys
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-api-keys-api-openapi.yml
- aid: mails-ai:mails-ai-billing-api
  name: mails-ai Billing API
  description: Usage metering and the Stripe billing portal.
  baseURL: https://api.mails.ai
  tags:
  - Billing
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-billing-api-openapi.yml
- aid: mails-ai:mails-ai-connected-apps-api
  name: mails-ai Connected Apps API
  description: 'The apps connected by signing in (the mails CLI, Claude, ChatGPT …): list and revoke them.'
  baseURL: https://api.mails.ai
  tags:
  - Connected Apps
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-connected-apps-api-openapi.yml
- aid: mails-ai:mails-ai-domains-api
  name: mails-ai Domains API
  description: Bring-your-own custom sending domains (records-only DNS verification).
  baseURL: https://api.mails.ai
  tags:
  - Domains
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-domains-api-openapi.yml
- aid: mails-ai:mails-ai-drafts-api
  name: mails-ai Drafts API
  description: Compose, edit, schedule, and send drafts.
  baseURL: https://api.mails.ai
  tags:
  - Drafts
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-drafts-api-openapi.yml
- aid: mails-ai:mails-ai-events-api
  name: mails-ai Events API
  description: Typed events (incl. classifier output) and the SSE live stream.
  baseURL: https://api.mails.ai
  tags:
  - Events
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-events-api-openapi.yml
- aid: mails-ai:mails-ai-inbound-api
  name: mails-ai Inbound API
  description: Received messages and the test-key inbound simulator.
  baseURL: https://api.mails.ai
  tags:
  - Inbound
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-inbound-api-openapi.yml
- aid: mails-ai:mails-ai-labels-api
  name: mails-ai Labels API
  description: 'Label objects: a name and a colour, applied to threads.'
  baseURL: https://api.mails.ai
  tags:
  - Labels
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-labels-api-openapi.yml
- aid: mails-ai:mails-ai-logs-api
  name: mails-ai Logs API
  description: Audit trail of state-changing operations.
  baseURL: https://api.mails.ai
  tags:
  - Logs
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-logs-api-openapi.yml
- aid: mails-ai:mails-ai-messages-api
  name: mails-ai Messages API
  description: Send, list, retrieve, reply, forward, schedule, and cancel email.
  baseURL: https://api.mails.ai
  tags:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-messages-api-openapi.yml
- aid: mails-ai:mails-ai-metrics-api
  name: mails-ai Metrics API
  description: Sent, delivered, bounced, complained, received and reply counts over time.
  baseURL: https://api.mails.ai
  tags:
  - Metrics
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-metrics-api-openapi.yml
- aid: mails-ai:mails-ai-public-api
  name: mails-ai Public API
  description: Unauthenticated endpoints (health, unsubscribe link targets).
  baseURL: https://api.mails.ai
  tags:
  - Public
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-public-api-openapi.yml
- aid: mails-ai:mails-ai-reputation-api
  name: mails-ai Reputation API
  description: Workspace- and agent-level deliverability reputation.
  baseURL: https://api.mails.ai
  tags:
  - Reputation
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-reputation-api-openapi.yml
- aid: mails-ai:mails-ai-search-api
  name: mails-ai Search API
  description: Full-text search over received and sent mail.
  baseURL: https://api.mails.ai
  tags:
  - Search
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-search-api-openapi.yml
- aid: mails-ai:mails-ai-suppression-api
  name: mails-ai Suppression API
  description: Suppression lookups and the consent allowlist.
  baseURL: https://api.mails.ai
  tags:
  - Suppression
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-suppression-api-openapi.yml
- aid: mails-ai:mails-ai-threads-api
  name: mails-ai Threads API
  description: Conversation threads grouping inbound + outbound messages, with read state, folders and labels.
  baseURL: https://api.mails.ai
  tags:
  - Threads
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-threads-api-openapi.yml
- aid: mails-ai:mails-ai-webhooks-api
  name: mails-ai Webhooks API
  description: Endpoint registration, delivery history, test, and replay.
  baseURL: https://api.mails.ai
  tags:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/mails-ai-webhooks-api-openapi.yml
x-coverage:
  state: unreadable
  reason: js-rendered-docs
  detail: Provider docs are rendered via JavaScript and no machine‑readable OpenAPI spec was found.
  evidence:
  - url: https://mails.ai
    status: 200
  checked: '2026-10-31'
x-enrichment:
  date: '2026-10-31'
  status: enriched
  artifacts_added: 38
  pass: modular-v1
  engine: identity=local,contract=local,surfaces=local,docs=local,regulatory=local

mails-ai API — frequently asked questions

Does mails-ai have an API?

Yes. APIs.io lists 19 APIs from mails-ai, including mails-ai Account API, mails-ai Agents API and mails-ai API Keys API, and 16 more.

Is there an OpenAPI specification for the mails-ai API?

Yes. APIs.io indexes 19 OpenAPI specifications for mails-ai, each linked for download from this page.

How do I authenticate with the mails-ai API?

mails-ai documents its authentication (1 scheme). The details are profiled on APIs.io as Mails Ai Authentication.

How much does the mails-ai API cost?

APIs.io lists 3 pricing plans for mails-ai, with each plan's price, limits and inclusions under Pricing Plans on this page.

Does mails-ai have an MCP server?

Yes. APIs.io lists 1 MCP server for mails-ai: Remote MCP server at help.mails.ai.

Is the mails-ai API ready for AI agents?

mails-ai has a Kin Score of 64.4 out of 100 (strong) and an Agent Readiness score of 64.7 (agent-native), scored by API Evangelist on 2026-10-31.

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