DEV Community: ReceiveHQ

Let your agent receive email when it needs to

ReceiveHQ — Fri, 11 Sep 2026 08:34:44 +0000

I'm Sebastian, CTO at ReceiveHQ (Cortena B.V.). This is a concrete walkthrough of one feature we use ourselves: giving Cursor or Claude a real inbound mailbox over MCP, without waiting for a webhook handler to exist.

The problem

Agent workflows often need email mid-task: a vendor sends a confirmation, a support reply lands, a magic link arrives, or you want the agent to triage overnight mail. Most inbound products assume you already have a public HTTPS endpoint and a parser wired up. Agents don't.

Blackhole first, webhook later

ReceiveHQ endpoints come in two kinds:

Kind	URL	What happens

Create an account at https://receivehq.com (magic-link sign-in).
Add the MCP server to your client:

{
  "mcpServers": {
    "receivehq": {
      "url": "https://receivehq.com/api/mcp"
    }
  }
}

Start the client — OAuth 2.1 + PKCE opens a browser for login and consent.
Revoke apps anytime under Settings → MCP in the console.

Endpoint docs live at https://receivehq.com/mcp.md (also /llms.txt).

Agent quick start

From Cursor, Claude, or another MCP client:

Run setup_inbound_domain with endpointKind: "blackhole" (no endpointUrl), or create the domain then create_inbound_domain_endpoint.
Point MX to mx.receivehq.com, then verify_inbound_domain_mx.## What else the agent can do

Tenants, domains, and endpoints (CRUD)
Search messages, inspect delivery attempts, resend
Invite teammates
Billing: Checkout / Customer Portal URLs
Fetch retained attempt and raw-mail objects by key (14-day evidence window)

Scopes: mcp:read for reads, mcp:admin for mutations. Tokens are user-scoped across that user's tenants.

Why this beats "paste the email into chat"

Real SMTP address on your domain (or a ReceiveHQ receive domain)
MIME parsed once; raw .eml retained for support and compliance
Same account can later fan out to webhooks without re-ingesting history
Hosted in Germany (Hetzner); DPA / sub-processors / hosting / imprint are public for GDPR buyers

Try it

Sign up: https://receivehq.com
Connect MCP: https://receivehq.com/api/mcp
Create a blackhole endpoint and send yourself a test message
Ask the agent to list_messages

Pricing: €10/mo or €100/yr for up to 100k inbound emails; first 10 free per tenant.

Trust links: hosting · DPA · sub-processors · imprint

Read mail with list_messages / get_message / list_deliveries.

When you are ready for production delivery, create or update an endpoint as webhook with your URL and payloadFormat (postmark, Mailgun/SendGrid, or CloudMailin). Same mailbox, no DNS redo.

Blackhole is the agent-friendly path: capture mail now, decide routing later.

Launching ReceiveHQ: inbound email webhook, hosted in Germany

ReceiveHQ — Thu, 10 Sep 2026 19:09:40 +0000

We're launching ReceiveHQ — inbound email infrastructure for teams that need SMTP in and HTTPS out, without rewriting webhook handlers or shipping mail through US-first relays.

https://receivehq.com

What it is

ReceiveHQ receives mail on your domain, parses MIME, and delivers it to your app as webhooks in the same shapes used by Postmark, Mailgun/SendGrid, and CloudMailin. Point your MX records at ReceiveHQ and keep the parser you already trust.

It is inbound-only, flat-priced, and hosted in Germany for GDPR-minded and EU-only stacks.

Why we built it

Moving off Postmark, Mailgun, SendGrid, or CloudMailin inbound often means two migrations: DNS and the webhook contract. ReceiveHQ makes the second one optional.

For EU buyers, “maybe an EU region” on a US product is often not enough for invoices, payroll, or support mail. ReceiveHQ runs on German infrastructure by default — not as a checkbox.

Features live today

Drop-in inbound webhooks

Postmark-compatible JSON: From, To, OriginalRecipient, TextBody, HtmlBody, attachments, headers, raw email, and more
Mailgun / SendGrid multipart: text / html, body-plain / body-html, envelope, attachment fields, and raw MIME
CloudMailin-compatible JSON: envelope, headers, plain text, HTML, and base64 attachm- Multi-tenant domains, address filters, and optional Basic auth on webhooks
14-day retention of raw mail and attempt logs for support/compliance evidence
Blackhole endpoints to receive and store mail without forwarding, useful when an agent reads the inbox via MCP/API before a webhook URL exists

Agent-native MCP

Connect Cursor, Claude, or another MCP client over OAuth 2.1 + PKCE.

Endpoint: https://receivehq.com/api/mcp
Configure domains, create blackhole or webhook endpoints, search messages, inspect deliveries, invite teammates, and manage billing from the agent
Agent docs: /llms.txt and /mcp.md

EU / GDPR posture

Hosting declaration: Germany / Hetzner
DPA
Sub-processors
Imprint (Cortena B.V., Netherlands)

Pricing

€10 / month for up to 100,000 inbound emails
Or €100 / year
First 10 emails free per tenant, with up to 3 trial tenants

There is no outbound bundle required to unlock inbound.

Try it

Sign up at receivehq.com
Add your receive domain and set MX
Pick the Postmark, Mailgun/SendGrid, or CloudMailin payload format
Or connect MCP and create a blackhole endpoint to start reading mail immediately

Webhook API docs are on the site. Feedback is especially welcome from anyone who has migrated an established inbound integration: which provider-specific edge cases were hardest to preserve?

Disclosure: I work on ReceiveHQ as CTO & Co-founder of Cortena B.V.

—

Sebastian Lagemann

https://receivehq.com · listings@receivehq.com

Who it is for

EU / GDPR-sensitive products that already speak Postmark, Mailgun, SendGrid, or CloudMailin inbound
Teams tired of SES + SNS + Lambda glue just to get email into an HTTP handler
Agent workflows that need a real inbound mailbox readable and configurable over MCP ents

Production inbound

SMTP in → HTTPS out, with multi-endpoint fan-out
Automatic retry backoff (1m → 5m → 30m → 1h → 2h), per-endpoint attempt limits, and HTTP 406 to permanently drop
Activity console with message search, delivery attempts, request/response logs, raw .eml, and resend with To / OriginalRecipient overrides