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Build on Mueslimail
Email inboxes for AI agents over a REST API and an MCP server. Start with the quickstart, look up an endpoint in the reference, or hand the inbox tools straight to your agent.
- Get startedCreate an inbox, receive a message and reply in thread, in five minutes and with plain HTTP.Read the quickstart
- API referenceEvery endpoint of the REST API with its parameters, responses and errors, generated from the OpenAPI file.Open the reference
- MCP for agentsConnect Claude Code, Cursor or Codex to the MCP server and the inbox operations become tools.Connect an agent
- ChangelogEvery release, with the API notes.
- Versions and SDKsGo and TypeScript clients, deprecation policy.
- WebhooksSigned events, retries and verification.
- ErrorsEvery error code and what to do about it.
Endpoints
- REST base URL
- https://api.mueslimail.com/v1
- MCP
- https://api.mueslimail.com/mcp
- OpenAPI
- https://api.mueslimail.com/openapi.yaml
- For agents
- /llms.txt indexes every page; each page has a Markdown twin.
Get started
- InboxesCreate, list, rename and delete inboxes. One inbox per agent, per user or per task.
- Messages and threadsHow inbound mail is parsed, threaded, labeled and screened before your agent reads it.
- SearchFull text search over the messages of an inbox, with the criteria applied to the message.
- BatchOne request, up to 1.000 messages, one outcome per id: archive, read state, labels and delete.
- Sending and replyingSend new messages, reply in thread and retry safely with Idempotency-Key.
- AttachmentsSend attachments as base64 and download received ones.
- RulesTyped conditions and actions that run on every message, with a written order of evaluation.
Platform
- Custom domainsSend and receive from your own domain: DNS records, verification and limits.
- WebhooksSigned event delivery: event types, payload, retries and signature verification.
- MCPUse inboxes as MCP tools from Claude Code, Cursor, Codex and other MCP clients.
- API logEvery call your keys made, with the request and the response redacted, kept seven days.
- Custom rolesNamed sets of permissions, assigned to people and to brand groups.
Reference
- ErrorsThe error envelope and every error code the API returns.
- LimitsPlan limits, rate limits and size limits enforced by the API.
- Versions and SDKsHow /v1 and /v0 relate, what the deprecation headers mean, and the official clients.
- ChangelogEvery release of Mueslimail, newest first, with the API changes developers need to know about.
- API referenceEvery REST endpoint and object, generated from the OpenAPI file.
About
Mueslimail gives every agent its own email address. Mail arrives as parsed threads, events as signed webhooks, and every inbound message is screened before an agent reads it. The service is hosted in the EU, on servers in Germany. Product, pricing and the console live on mueslimail.com.