Email Workflow API Specification & Integration Reference
Public API Page

POST Email Workflow API

/api/v1/ai/email-workflow

Determine the most appropriate business action for an email using AI. The API analyzes the email and recommends workflow decisions such as replying, forwarding, assigning, archiving, escalating, or routing.

Base Billing 1 Credit
Target Latency < 150ms (p50)
Client Timeout 5.0s (recommended)
SLA Guarantee 99.9% Uptime
JSON Contract Deterministic v1

Architecture Role & AI Definition

Email Workflow API provides low-latency, deterministic REST execution for production engineering workflows. It processes structured payloads with strict schema validation, returns uniform JSON envelopes, and is secured via SHA-256 API key authentication with atomic credit pre-authorization locks.

Production Reliability Guidelines

1. Strict Timeout Windows

Configure a hard client timeout of 5 to 8 seconds. If network latency spikes, cancel connection to avoid holding open sockets in worker pools.

2. Exponential Backoff with Jitter

Upon receiving 429 Rate Limit or transient 5xx, pause with exponential backoff:
wait = min(max_backoff, base * 2^attempt + jitter).

3. Atomic Pre-Auth Locks

RSFlowHub acquires an atomic lock verifying base credits before model invocation. If validation fails, zero credits are deducted.

Request Body Parameters

Field Type Required Description
email_content string Required The main body of the email to route (Max: 20,000 characters).
subject string Optional Optional email subject line.
allowed_actions array of strings Optional Optional strict list of allowed actions (e.g., ["reply", "forward", "archive", "escalate"]).
allowed_departments array of strings Optional Optional strict list of allowed departments (e.g., ["support", "billing", "sales", "hr"]).
workflow_first boolean Optional Optional. If true, runs in Workflow-First Mode. The API internally executes both analysis and reply drafting, returning all results (insights and drafted reply) in a single unified JSON response. Default is false.
custom_instructions string Optional Optional instructions to guide routing decisions.
model string Optional Optional AI model to use.

Example Request (Workflow-First)

Requesting action and department routing while enabling workflow_first to get a single unified payload.

JSON Request
{
  "subject": "Double charged on my last invoice!",
  "email_content": "Hello, I was looking at my bank statement and I was charged twice for my Pro subscription this month. Please refund one of the charges immediately.",
  "allowed_actions": ["reply", "forward", "escalate", "archive"],
  "allowed_departments": ["support", "billing", "sales"],
  "workflow_first": true
}
curl-trigger.sh cURL
curl -X POST https://rsflowhub.com/api/v1/ai/email-workflow \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "subject": "Double charged on my last invoice!",
    "email_content": "Hello, I was looking at my bank statement and I was charged twice for my Pro subscription this month. Please refund one of the charges immediately.",
    "allowed_actions": ["reply", "forward", "escalate", "archive"],
    "allowed_departments": ["support", "billing", "sales"],
    "workflow_first": true
  }'

Example Response

Because workflow_first: true was passed, the API outputs the routing decision along with nested analysis and reply drafts.

response.json JSON Response
200 OK 118ms
{
  "success": true,
  "data": {
    "result": {
      "action": "reply",
      "department": "billing",
      "confidence": 0.98,
      "reasoning": "The customer is reporting a billing issue requiring an immediate refund, matching the billing department scope.",
      "analysis": {
        "category": "billing",
        "intent": "refund_request",
        "priority": "high",
        "sentiment": "negative",
        "language": "en",
        "entities": {
          "refund_amount": "$49"
        },
        "summary": "Customer demands refund for double charge on subscription."
      },
      "reply": {
        "reply_text": "Hi John, Thank you for reaching out. We have received your query regarding the duplicate $49 charge on your invoice and have routed this to our billing specialist for priority review.",
        "requires_human_escalation": false,
        "escalation_reason": null
      }
    }
  },
  "meta": {
    "credits_used": 3,
    "credits_remaining": 995
  }
}

API Request Example

Use the cURL snippet below to test the endpoint.

curl-trigger.sh cURL
curl -X POST 'https://rsflowhub.com/api/v1/ai/email-workflow' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "subject": "Cancel order #8849",
    "email_content": "Please cancel order 8849.",
    "allowed_actions": [
        "reply",
        "forward",
        "escalate"
    ],
    "workflow_first": false
}'

Common Failure Modes & Troubleshooting Matrix

HTTP Code Error Code Root Cause Recommended Remediation
400 bad_request Malformed JSON syntax or missing required top-level parameters. Validate JSON payload with Content-Type: application/json and ensure all required fields are present.
401 unauthorized Missing, revoked, or incorrectly formatted x-api-key header. Verify API key exists in Dashboard → API Keys and pass in x-api-key or Authorization: Bearer.
402 insufficient_credits Account credit balance is lower than the base required credits (2 credits). Top up credits in billing settings or enable auto-recharge to prevent pipeline interruption.
422 validation_error Input failed parameter constraints (e.g., character length exceeded or invalid array types). Review parameters table above and adjust payload length, types, or structure accordingly.
429 rate_limit_exceeded Concurrency limit (60 requests/minute default) reached for this endpoint key. Back off and retry using the timestamp in Retry-After response header, or batch requests.

Technical Q&A (FAQ)

We recommend setting a client timeout of 5 to 8 seconds. While average latency is under 150ms, large input payloads or complex reasoning models may require additional processing time.

RSFlowHub uses an atomic pre-flight check. Before processing, the gateway validates that your wallet has at least 2 base credits. If the request fails validation (422) or is malformed (400), no credits are charged.

When a 429 is received, your application should respect the 'Retry-After' header and use an exponential backoff retry policy with randomized jitter to prevent thundering herd problems.

Every successful response returns { "success": true, "data": { ... }, "meta": { "credits_used": int, "credits_remaining": int } }.

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