OpenSend docs
Email Best Practices Skill
Guardrails for production email systems.
Verify domains, honor unsubscribe and suppression state, avoid hardcoding secrets, and test with safe recipients before production.
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This page is intentionally concise. Use the neighboring guides below for the next implementation details, route contracts, or operational steps.
AI Onboarding
Onboard coding agents to OpenSend.
Agent Email Inbox Skill
Build an agent inbox on top of OpenSend receiving without exposing raw mailbox access to the agent runtime.
React Email Skill
Build HTML email with React components.
Custom Event Schemas
Define and validate custom event payloads.
Migrate from Resend
Use the in-tree OpenSend migration verifier to inspect an existing Resend integration before you point it at OpenSend. Always pass the application repository you want to scan; the verifier fails closed when the target directory is omitted.
Send emails with Java and Kotlin
Use the first-party OpenSend JVM SDK from plain Java, Kotlin, Spring Boot services, workers, and command-line applications. The package lives in this repository at packages/jvm-sdk while registry publishing is prepared. This is a partial, blocking-only SDK for emails, contacts, domains, and suppressions; use the REST API and /openapi.json for other resources.