Sendmux

Sendmux is an email API that gives every AI agent a real inbox. Send and receive, route outbound through your own providers, and fail over automatically.

Sendmux is an email API that gives every AI agent a real inbox. Send and receive, route outbound through your own providers, and fail over automatically. Create agent inboxes, send through your providers, and route with quotas, weighted delivery, and failover from one API. # Give your OpenClaw agent a real inbox npx skills add Sendmux/skills # Then grant the tools, either: # → connect the hosted MCP endpoint (OAuth) # https://mcp.sendmux.ai/mcp # → or create a scoped API key in the dashboard # Skills teach the workflow; MCP or a key grants access. # Add the hosted MCP endpoint claude mcp add sendmux \ --transport http https://mcp.sendmux.ai/mcp ✓ server added · oauth flow opens in browser ✓ …

• Sendmux - The Email API for AI Agents, with Inboxes Product
• Links, headers, and attachments available on request
• Batch message actions accept up to 100 IDs
• Idempotency-Key support for safe HTTP retries
• Text, HTML, X-headers, and up to 10 attachments
• API response returns the queued message ID
• Second, minute, hour, and day quota windows
• Percentage weights for eligible providers

Prices listed on the Sendmux pricing page: $150/mo

Source: sendmux.ai pricing page. Price checked 2026-08-21. Confirm current plans before buying.

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