Sentiment Analysis API Specification & Integration Reference

POST Sentiment Analysis API

/api/v1/ai/sentiment-analysis

Analyze the emotional tone of text to identify positive, negative, neutral, or mixed sentiments.

Base Billing 1 Credit
Typical Response 1-3 s
Client Timeout 15-30 s (recommended)
Provider Fallback Automatic
JSON Contract Envelope v1

Architecture Role & AI Definition

Sentiment Analysis 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.

Freemium API
This API is part of the utility tier. Every plan includes a shared monthly quota of free utility requests (1,000/month on the Free plan). Credits are only used after the quota is reached.

Request Body Parameters

Field Type Required Description
text string Required The text content you want to analyze (Max: 5,000 characters).
aspects array of strings Optional Optional list of specific topics to analyze sentiment for (e.g., ["UI", "billing", "speed"]). Max 10 items.
model string Optional Optional. AI model to use for classification. Defaults to platform optimal model.

Example Request (Basic)

JSON Request
{
  "text": "The new dashboard is incredibly fast and looks amazing!"
}
curl-trigger.sh cURL
curl -X POST https://rsflowhub.com/api/v1/ai/sentiment-analysis \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "text": "The new dashboard is incredibly fast and looks amazing!"
  }'

Example Response (Basic)

The API guarantees the sentiment string will be one of: positive, negative, neutral, or mixed.

response.json JSON Response
200 OK
{
  "success": true,
  "request_id": "req_7f3a9c2d1e4b8a6f",
  "data": {
    "result": {
      "sentiment": "positive",
      "confidence": 0.98
    }
  },
  "meta": {
    "version": "v1",
    "timestamp": "2026-09-27T12:34:56+00:00"
  }
}

Advanced Example (Aspect-Based Sentiment)

Provide an aspects array to get targeted sentiment scores for specific subjects mentioned in the text.

Advanced JSON Request
{
  "text": "The dashboard is really fast, but the billing page is confusing and support took too long.",
  "aspects": ["dashboard", "billing", "support"]
}
response.json Advanced JSON Response
200 OK
{
  "success": true,
  "request_id": "req_7f3a9c2d1e4b8a6f",
  "data": {
    "result": {
      "sentiment": "mixed",
      "confidence": 0.85,
      "aspect_sentiments": [
        {
          "aspect": "dashboard",
          "sentiment": "positive",
          "confidence": 0.95
        },
        {
          "aspect": "billing",
          "sentiment": "negative",
          "confidence": 0.92
        },
        {
          "aspect": "support",
          "sentiment": "negative",
          "confidence": 0.88
        }
      ]
    }
  },
  "meta": {
    "version": "v1",
    "timestamp": "2026-09-27T12:34:56+00:00"
  }
}

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/sentiment-analysis' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "text": "The dashboard is really fast, but the billing page is confusing.",
    "aspects": [
        "dashboard",
        "billing"
    ]
}'

Want to try it without code? Test this request in the live Playground.


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 (1 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)

Each Sentiment Analysis API call costs 1 base credit, plus about 1 credit per 1,000 input characters. It is a utility endpoint, so it also counts toward the free monthly quota included in every plan (1,000 requests/month on the Free plan) before any credits are used. Failed calls are not charged.

The text field accepts up to 5,000 characters per request. Larger inputs return a 422 validation error, so split long content into chunks.

Sentiment Analysis API runs on Google Gemini (gemini-2.5-flash-lite), with automatic fallback to OpenAI (gpt-4.1-mini) if the primary provider fails or rate-limits. Models are tuned per task, so your integration does not change when we upgrade them.

Yes. Identical requests within 24 hours are answered from cache, which is faster and free or discounted in credits.

Most requests complete in 1 to 3 seconds; set a client timeout of 15 to 30 seconds to cover long inputs. On HTTP 429, wait for the Retry-After delay. Retry network errors once or twice with exponential backoff and jitter.

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