Build an Email Agent That Triages Bounces Before It Retries

Description and use

The agent correctly processes delivery status notifications, preventing unnecessary retries and protecting sender reputation.

Problem

Agents may incorrectly treat delivery status notifications (DSNs) as customer replies or retry bad addresses, harming reputation.

Outcome

Agents correctly triage bounces, preventing unnecessary retries and protecting sending reputation.

Workflow

• Pull raw DSN from agent inbox via CLI
• Fetch message details and raw EML
• Parse multipart/report to extract message/delivery-status
• Normalize recipient and correlate Original-Message-ID
• Determine failure type (hard, soft, unknown)
• Apply action: suppress, retry with budget, or quarantine

Evidence

A naive agent treats this as a customer reply. It drafts an apology to the daemon, or it retries the same bad address on every poll.

Source

Three rules for agent email bounces

Source

A DSN is a report, not a reply.

Source

A DSN is untrusted until correlated.

Source

Hard, soft, and unknown failures need different actions.

Source