# MailOptin

**Canonical:** https://apis.io/providers/mailoptin/  
**Website:** https://mailoptin.io/  
**APIs profiled:** 1

MailOptin is a WordPress lead-generation and email-automation plugin that converts website visitors into subscribers with popups, slide-ins, notification bars and inline optin forms, then sends one-off newsletters and event-triggered automated emails. It connects WordPress to more than sixty email marketing platforms, CRMs, form plugins, e-commerce and membership systems — Mailchimp, ActiveCampaign, HubSpot, AWeber, Klaviyo, Brevo, Salesforce, WooCommerce and others — and can post optin submissions to an arbitrary endpoint through a generic webhook connection. MailOptin is self-hosted software rather than a hosted service: it publishes no product API, no OpenAPI and no client SDK, and all functionality runs inside the customer's own WordPress installation. Its own website, mailoptin.io, runs WordPress and does serve a public self-describing REST API together with an OAuth-protected Model Context Protocol server.

## Kin Score — 50.1 / 100 (developing)

Scored 2026-08-17 under rubric 0.11.0. Trend: flat (+0.0 from 50.1).

| Facet | Score |
|---|---|
| Discoverability | 75.9 |
| Contract Quality | 51.6 |
| Governance | 12.5 |
| Operational Transparency | 28.9 |
| Developer Ergonomics | 45.7 |
| Commercial Clarity | 76.3 |

## Agent readiness — 48.2 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | no |
| MCP Server | yes |
| Auth Clarity | yes |
| Idempotency | no |
| Error Semantics | documented |
| OpenAPI Examples | no |
| Rate Limit Signal | documented |
| Event Surface Described | yes |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## APIs (1)

- **MailOptin Site REST API and MCP Server** — The WordPress REST API served by mailoptin.io, plus the Model Context Protocol server exposed through the WordPress MCP Adapter at the mcp namespace. The REST root is a public, ...

## MCP servers (1)

- **mailoptin-mcp.yml**

## Security (2)

- **Mailoptin Authentication** — 3 schemes
- **Mailoptin Domain Security** — TLSv1.3 · HSTS · DMARC

## Plans (1)

- **Mailoptin Plans Pricing**

## Tags

Company, Email Marketing, Marketing Automation, Lead Generation, WordPress, Newsletters, Webhooks, Model Context Protocol, Plugins

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/mailoptin/). Scores are computed from the provider's own public artifacts under a published rubric.