🔌 Developer API

Authentication

All API requests require an API key passed via the Authorization header:

Authorization: Bearer YOUR_API_KEY

API keys are available through the Developer Dashboard at https://langou-ime.com/developer. Each key is scoped to specific permissions (read, write, admin) and can be rotated or revoked independently.

Rate limits: 100 requests/minute for API keys. Contact us for higher limits.

AI Reply Generation Endpoint

POST /v1/replies/generate

Generate AI-powered chat replies based on conversation context and desired style.

Request body:

{
  "context": [
    {"sender": "user", "text": "Did you finish the report?"},
    {"sender": "me", "text": "Almost done, just need the final numbers"},
    {"sender": "user", "text": "Can you send it by 3 PM?"}
  ],
  "style": "professional",
  "count": 3,
  "language": "en"
}

Response:

{
  "suggestions": [
    "Absolutely. I'll have the final report with all numbers ready for you by 3 PM.",
    "Yes, I'll make sure you have it before 3 PM. Just compiling the final data now.",
    "3 PM works perfectly. I'll send it over with the completed numbers."
  ],
  "style": "professional",
  "model": "mimo-v2.5-pro",
  "generation_time_ms": 842
}

Style Customization API

POST /v1/styles/custom

Create custom reply styles with fine-grained personality parameters.

Request body:

{
  "name": "Coach",
  "base_style": "warm",
  "parameters": {
    "formality": 0.3,
    "enthusiasm": 0.8,
    "empathy": 0.9,
    "directness": 0.6,
    "humor": 0.2,
    "emotional_expression": 0.7
  },
  "description": "Encouraging, supportive tone for mentoring"
}

Prompt Optimization Endpoint

POST /v1/prompts/optimize

Optimize prompts for use with ChatGPT, DeepSeek, Claude, or other AI models.

Request body:

{
  "original_text": "Write an email about the project delay",
  "target_model": "chatgpt",
  "detail_level": "detailed"
}

Response:

{
  "optimized": "Write a professional project delay notification email addressed to stakeholders. Include: (1) acknowledgment of the delay, (2) the reason for the delay, (3) revised timeline, (4) mitigation steps being taken. Use a transparent but constructive tone.",
  "concise": "Draft a stakeholder email about a project delay: transparent tone, include reason, new timeline, and next steps.",
  "improvements": ["Added stakeholder context", "Specified email structure", "Clarified tone guidance"]
}

Dictionary Management API

POST /v1/dictionary/entries — Add entries to user dictionary
GET /v1/dictionary/entries — List dictionary entries
DELETE /v1/dictionary/entries — Remove dictionary entries

Manage custom dictionary entries programmatically — useful for enterprise deployments that need to seed industry-specific terminology.

Webhook Integration

Langou supports outgoing webhooks to notify your application when certain events occur:

• reply.sent: Fired when a user sends an AI-generated reply
• style.changed: Fired when the user switches reply styles
• feedback.received: Fired when a user rates an AI suggestion
• error.occurred: Fired when an AI generation fails

Webhooks are configured via the Developer Dashboard with optional retry logic, HMAC signature verification, and custom payload filtering.

SDKs & Libraries

Official client libraries are available for:

• Python: pip install langou-api
• JavaScript/TypeScript: npm install langou-api
• Java/Kotlin: Available via Maven Central
• Swift: Available via Swift Package Manager

Community-maintained libraries are listed in our resources. See the full API reference at docs.langou-ime.com.