# Amazon API Gateway

[Amazon API Gateway](https://aws.amazon.com/api-gateway/) is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale. APIs act as the "front door" for applications to access data, business logic, or functionality from your backend services. Using API Gateway, you can create RESTful APIs and WebSocket APIs that enable real-time two-way communication applications. API Gateway supports containerized and serverless workloads, as well as web applications.

API Gateway handles all the tasks involved in accepting and processing up to hundreds of thousands of concurrent API calls, including traffic management, CORS support, authorization and access control, throttling, monitoring, and API version management. API Gateway has no minimum fees or startup costs. You pay for the API calls you receive and the amount of data transferred out and, with the API Gateway tiered pricing model, you can reduce your cost as your API usage scales.

## LLM

See a [usage example](/docs/modules/model_io/models/llms/integrations/amazon_api_gateway_example.html).

```python
from langchain.llms import AmazonAPIGateway

api_url = "https://<api_gateway_id>.execute-api.<region>.amazonaws.com/LATEST/HF"
llm = AmazonAPIGateway(api_url=api_url)

# These are sample parameters for Falcon 40B Instruct Deployed from Amazon SageMaker JumpStart
parameters = {
    "max_new_tokens": 100,
    "num_return_sequences": 1,
    "top_k": 50,
    "top_p": 0.95,
    "do_sample": False,
    "return_full_text": True,
    "temperature": 0.2,
}

prompt = "what day comes after Friday?"
llm.model_kwargs = parameters
llm(prompt)
>>> 'what day comes after Friday?\nSaturday'
```

## Agent

```python
from langchain.agents import load_tools
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from langchain.llms import AmazonAPIGateway

api_url = "https://<api_gateway_id>.execute-api.<region>.amazonaws.com/LATEST/HF"
llm = AmazonAPIGateway(api_url=api_url)

parameters = {
    "max_new_tokens": 50,
    "num_return_sequences": 1,
    "top_k": 250,
    "top_p": 0.25,
    "do_sample": False,
    "temperature": 0.1,
}

llm.model_kwargs = parameters

# Next, let's load some tools to use. Note that the `llm-math` tool uses an LLM, so we need to pass that in.
tools = load_tools(["python_repl", "llm-math"], llm=llm)

# Finally, let's initialize an agent with the tools, the language model, and the type of agent we want to use.
agent = initialize_agent(
    tools,
    llm,
    agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
    verbose=True,
)

# Now let's test it out!
agent.run("""
Write a Python script that prints "Hello, world!"
""")

>>> 'Hello, world!'
```