Email Analyze API Specification & Integration Reference
API Endpoint Public API Page

POST Email Analyze API

/api/v1/ai/email-analyze

Analyze incoming emails using AI to extract structured insights such as category, intent, priority, sentiment, language, entities, and summary.

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 Analyze 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 analyze (Max: 20,000 characters).
subject string Optional Optional email subject line. Providing this increases analysis accuracy.
allowed_categories array of strings Optional Optional list of allowed categories. If provided, the AI forces the output category into one of these buckets.
allowed_intents array of strings Optional Optional list of allowed intents. If provided, the AI forces the output intent into one of these buckets.
custom_instructions string Optional Optional specific guidelines to customize the analysis or extraction process.
model string Optional Optional AI model to use.

Example Request

Send an email body with optional lists of expected categories and intents to get structured analysis data.

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 as this is unacceptable.",
  "allowed_categories": ["support", "billing", "spam", "sales"],
  "allowed_intents": ["refund_request", "cancellation", "login_issue"]
}
curl-trigger.sh cURL 
curl -X POST https://rsflowhub.com/api/v1/ai/email-analyze \
  -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 as this is unacceptable.",
    "allowed_categories": ["support", "billing", "spam", "sales"],
    "allowed_intents": ["refund_request", "cancellation", "login_issue"]
  }'

Example Response

The API analyzes the text using AI and returns high-accuracy structured insights.

response.json JSON Response
200 OK 118ms 
{
  "success": true,
  "data": {
    "result": {
      "category": "billing",
      "intent": "refund_request",
      "priority": "high",
      "sentiment": "negative",
      "language": "en",
      "entities": {
        "charge_amount": "$49",
        "billing_cycle": "monthly"
      },
      "summary": "The customer was double charged for their Pro subscription and is demanding an immediate refund."
    }
  },
  "meta": {
    "credits_used": 2,
    "credits_remaining": 998
  }
}

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-analyze' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "subject": "Issue with login",
    "email_content": "I cannot sign in to my account. It says password incorrect.",
    "allowed_categories": [
        "support",
        "billing",
        "sales"
    ]
}'

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 } }.

Ready to build?

Create your free account and make your first API call in minutes.

Get API Key Open Playground