Update README with serverless SDK documentation

- Add handler examples (sync, async, generator)
- Add input validation usage
- Add local development instructions
- Add CLI options and environment variables

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: chengzeyi

README.md

@@ -1,17 +1,135 @@
 # wavespeed-python
 
-WaveSpeedAI Python Client — Official Python SDK for WaveSpeedAI inference platform. This library provides a clean, unified, and high-performance API and serverless integration layer for your applications. Effortlessly connect to all WaveSpeedAI models and inference services with zero infrastructure overhead.
+WaveSpeedAI Python Client — Official Python SDK for WaveSpeedAI inference platform. This library provides a clean, unified, and high-performance API and serverless integration layer for your applications.
 
 ## Installation
 
 ```bash
 pip install wavespeed
 ```
 
-## Usage
+## Serverless Worker
+
+Build serverless workers compatible with RunPod infrastructure.
+
+### Basic Handler
+
+```python
+import wavespeed.serverless as serverless
+
+def handler(job):
+    job_input = job["input"]
+    result = job_input.get("prompt", "").upper()
+    return {"output": result}
+
+serverless.start({"handler": handler})
+```
+
+### Async Handler
+
+```python
+import wavespeed.serverless as serverless
+
+async def handler(job):
+    job_input = job["input"]
+    result = await process_async(job_input)
+    return {"output": result}
+
+serverless.start({"handler": handler})
+```
+
+### Generator Handler (Streaming)
 
 ```python
-import wavespeed
+import wavespeed.serverless as serverless
+
+def handler(job):
+    for i in range(10):
+        yield {"progress": i, "partial": f"chunk-{i}"}
+
+serverless.start({"handler": handler})
+```
+
+### Input Validation
+
+```python
+from wavespeed.serverless.utils import validate
+
+INPUT_SCHEMA = {
+    "prompt": {"type": str, "required": True},
+    "max_tokens": {"type": int, "required": False, "default": 100},
+    "temperature": {
+        "type": float,
+        "required": False,
+        "default": 0.7,
+        "constraints": lambda x: 0 <= x <= 2,
+    },
+}
+
+def handler(job):
+    result = validate(job["input"], INPUT_SCHEMA)
+    if "errors" in result:
+        return {"error": result["errors"]}
 
-print(wavespeed.__version__)
+    validated = result["validated_input"]
+    # process with validated input...
+    return {"output": "done"}
 ```
+
+## Local Development
+
+### Test with JSON Input
+
+```bash
+# Using CLI argument
+python handler.py --test_input '{"input": {"prompt": "hello"}}'
+
+# Using test_input.json file (auto-detected)
+echo '{"input": {"prompt": "hello"}}' > test_input.json
+python handler.py
+```
+
+### FastAPI Development Server
+
+```bash
+python handler.py --waverless_serve_api --waverless_api_port 8000
+```
+
+Then use the interactive Swagger UI at `http://localhost:8000/` or make requests:
+
+```bash
+# Synchronous execution
+curl -X POST http://localhost:8000/runsync \
+  -H "Content-Type: application/json" \
+  -d '{"input": {"prompt": "hello"}}'
+
+# Async execution
+curl -X POST http://localhost:8000/run \
+  -H "Content-Type: application/json" \
+  -d '{"input": {"prompt": "hello"}}'
+```
+
+## CLI Options
+
+| Option | Description |
+|--------|-------------|
+| `--test_input JSON` | Run locally with JSON test input |
+| `--waverless_serve_api` | Start FastAPI development server |
+| `--waverless_api_host HOST` | API server host (default: localhost) |
+| `--waverless_api_port PORT` | API server port (default: 8000) |
+| `--waverless_log_level LEVEL` | Log level (DEBUG, INFO, WARN, ERROR) |
+
+## Environment Variables
+
+The SDK auto-detects RunPod or native Waverless environments:
+
+| Variable | Description |
+|----------|-------------|
+| `RUNPOD_WEBHOOK_GET_JOB` | Job fetch endpoint |
+| `RUNPOD_WEBHOOK_POST_OUTPUT` | Result submission endpoint |
+| `RUNPOD_AI_API_KEY` | API authentication key |
+| `RUNPOD_POD_ID` | Worker/pod identifier |
+
+## License
+
+MIT