automations
Email Parser API Workflow for Inbound Message Extraction
Use a contract-first email parser API to capture inbound mail, extract typed fields from messages and attachments, and route output with retry and replay controls.
An email parser API turns inbound messages and attachments into structured records that applications can trust. Use it when shared inbox triage, mailbox polling, or one-off regex scripts no longer fit the workflow.
MailSlurp gives teams the intake layer and extraction workflow together: programmable inboxes, inbound email APIs, webhook events, schema-guided AI extraction, attachment handling, retry controls, and replayable message evidence.
Quick answer
Use this API workflow when your system needs to:
- receive inbound email and attachments through controlled inboxes
- extract typed JSON fields from message body, headers, metadata, and files
- validate required fields before writing to CRM, finance, support, or warehouse systems
- deliver parser output through webhooks, queues, or downstream APIs
- retry safely when a destination is down or a parse result needs review
- keep the original message available for audit, replay, and debugging
If you need the product overview first, start with AI email parser for structured data extraction. If you already know the parser belongs in an API workflow, use the sequence below.
When you are ready to build the intake flow, start a MailSlurp parser workflow and connect the inbox, webhook, schema, and replay controls in one place.
Route the right work to the right MailSlurp surface
MailSlurp has a few related surfaces. Use them deliberately:
- Inbound email API receives messages, attachments, headers, and metadata.
- Email webhooks deliver new-message events to your services in real time.
- AI email parser extracts schema-guided JSON from messages and attachments.
- Email parser API is the implementation workflow that ties intake, extraction, validation, delivery, and replay together.
- Inbound email routing handles routing, aliases, forwarding, fallback lanes, and review destinations.
That split keeps parsing from becoming a vague "email automation" project. Each layer owns one job.
Contract-first parser API flow
- Create or select a dedicated inbound address for the workflow.
- Capture the inbound event and message identifiers through webhook or API polling.
- Fetch the full message, including body, headers, metadata, and attachments.
- Submit the parse request with an explicit output schema and schema version.
- Validate required fields, data types, confidence, and business rules.
- Route the parsed result to the destination with an idempotency key and trace ID.
- Persist the original message, parse result, destination response, and replay metadata.
- Replay failed or low-confidence records after review without losing the original evidence.
Example output contract
The parser contract should be small, explicit, and owned by the downstream workflow. For an invoice intake workflow, the contract might require:
| Field | Type | Why it matters |
|---|---|---|
vendorName |
string | Identifies the supplier record or review lane |
invoiceNumber |
string | Prevents duplicate finance records |
dueDate |
date | Drives payment workflow timing |
totalAmount |
number | Supports approval thresholds |
currency |
string | Avoids silent accounting mistakes |
attachmentIds |
string array | Keeps parsed data tied to source files |
confidence |
number | Decides whether to write, review, or replay |
Support, lead, claims, and order workflows should define different contracts. The API shape should match the record your downstream system needs, not the email format the sender happened to use.
API design checklist
- Use dedicated inboxes or aliases by workflow, customer, sender class, or environment.
- Require a schema version in every parse request.
- Return typed payloads plus extraction metadata.
- Separate hard errors, such as invalid contracts, from soft errors, such as partial extraction.
- Include original message IDs, attachment IDs, replay tokens, and trace IDs.
- Emit destination-safe idempotency keys for every write.
- Store raw message evidence beside the parsed result.
- Add test fixtures for representative senders, attachments, and template changes.
Webhook and queue delivery pattern
Many teams start with webhook delivery because it removes mailbox polling and keeps parser work close to the receiving service.
Use this pattern:
- Attach a MailSlurp webhook to the inbox that receives the workflow mail.
- Verify the webhook handler accepts the event payload and can fetch full message context.
- Run the parser request with the schema for that workflow.
- Validate the extracted record before sending it to CRM, ticketing, finance, or a queue.
- Return success only after the event is durably recorded.
- Use replay when the parser, destination, or network path fails.
For event setup, use Email webhooks and Testing webhooks. For routing and fallback destinations, use Inbound email routing.
Failure budget and replay policy
Define these before production launch:
- Max allowed parse failure rate per workflow.
- Retry limits by destination criticality.
- Human review path for low-confidence outputs.
- Replay ownership and SLA for blocked records.
- Rollback rule when schema changes degrade quality.
The safest parser API workflows treat low-confidence results as a first-class state, not as a hidden warning. Send those records to review, keep the source message visible, and replay them after the contract or parser settings are corrected.
What to test before launch
Before a parser workflow handles production mail, test these cases:
- a normal message with all expected fields
- a message with missing required fields
- a sender template change
- a duplicate message or repeated webhook event
- a PDF or image attachment that contains the primary data
- a downstream outage followed by replay
- a low-confidence extraction that should go to review
- a schema version change that should not break older records
Use MailSlurp test inboxes, webhook logs, and stored message fixtures so the parser workflow can be checked before a release and after sender templates change.