> For the complete documentation index, see [llms.txt](https://doc.aissist.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.aissist.io/integrations/aws-lambda.md).

# AWS Lambda

*Last updated: May 15, 2026*

Use AWS Lambda when you want Aissist to access internal systems through a controlled API layer.

This works well when you do not want to expose your database or backend systems directly.

With Lambda, you can:

* control exactly what data Aissist can read
* filter or transform the returned data
* expose only the fields and actions you want

### How the pattern works

1. Build a small Lambda function for the data or action you want to expose.
2. Publish it through a Function URL or API Gateway.
3. Connect that endpoint through the [RESTful API](/integrations/restful-api.md) integration.
4. Create actions that call the endpoint.

### Example flow

<details>

<summary>Step 1: write the Lambda function</summary>

Create a small function that returns only the data Aissist needs.

This example fetches booking details by booking ID:

```python
import mysql.connector

def lambda_handler(event, context):
    secrets = dict()
    with open("secrets.json") as input_fp:
        secrets = json.load(input_fp)
    
    database = mysql.connector.connect(
        host=secrets["host"],
        database=secrets["database"],
        user=secrets["user"],
        password=secrets["password"]
    )

    query = """ SELECT * FROM cr_booking WHERE id = %s """
    cursor = database.cursor()
    cursor.execute(query, (json.loads(event['body'])["booking_id"],))
    
    column_names = [col[0] for col in cursor.description]
    bookings = [dict(zip(column_names, row)) for row in cursor.fetchall()]
    
    return {"book_details": bookings}
```

</details>

<details>

<summary>Step 2: package the function</summary>

Package the function, dependencies, and any required configuration into a zip file.

1. Install the MySQL connector package:

   ```bash
   pip3 install --target ./packages mysql-connector
   ```
2. Create the deployment package:

   ```bash
   cd ./packages
   zip -r ../deployment_package.zip .
   cd ..
   zip deployment_package.zip lambda_function.py
   zip deployment_package.zip secrets.json
   ```

</details>

<details>

<summary>Step 3: create the Lambda function in AWS</summary>

1. Go to the **AWS Lambda Console**.
2. Create a new **Lambda function**.
3. Enable a **Function URL** for a simple setup, or use **API Gateway** for stricter control.
4. Upload your `deployment_package.zip`.
5. Copy the public endpoint URL.

<figure><img src="/files/PNJ5v891TqTRMxnhLLzr" alt=""><figcaption></figcaption></figure>

</details>

<details>

<summary>Step 4: connect Lambda to Aissist</summary>

Add the endpoint through the [RESTful API](/integrations/restful-api.md) integration.

Then create actions that call that endpoint.

Use the Lambda Function URL or API Gateway URL as the API endpoint.

</details>

### Why use AWS Lambda

AWS Lambda is useful because it is:

* **Secure** — expose only the data and operations you allow
* **Scalable** — no server management required
* **Cost-efficient** — pay only when it runs
* **Flexible** — shape the response for Aissist before it returns

### Best practice

Keep each Lambda endpoint focused on one job.

Return only the fields Aissist needs, then test the action in [Action Debugger](/integrations/action-debugger.md).