What is aws-sigv4-req-builder?

This Claude skill automates the generation of authenticated Python code for AWS APIs by converting cURL requests into SigV4-signed scripts. It simplifies the process of interacting with undocumented or internal AWS services, ensuring secure and proper authentication using boto3 and botocore without requiring manual header construction.

When should I use aws-sigv4-req-builder?

aws-sigv4-req-builder is useful in the following scenarios: • Accessing undocumented or internal AWS APIs that are not yet supported by the official AWS SDK (Boto3). • Converting browser-captured network requests from the AWS Console into reusable Python automation scripts. • Building custom API clients for AWS services with complex Signature Version 4 (SigV4) authentication requirements. • Rapidly prototyping AWS integrations by bypassing the need to manually sign requests and manage authentication headers.

name	aws-sigv4-req-builder
description	Generate Python code to call undocumented AWS APIs using SigV4 authentication from cURL requests captured in browser dev tools. This skill should be used when users need to create Python functions that call AWS internal or undocumented APIs with proper AWS Signature Version 4 authentication.

AWS SigV4 Request Builder

Generate Python code to call undocumented AWS APIs using AWS Signature Version 4 authentication from cURL requests.

When to Use

Use this skill when users need to:

Call undocumented AWS APIs from Python
Convert browser network requests to authenticated Python code
Build API clients for AWS services without official SDK support

How to Use

Step 1: Get cURL from User

Ask the user for the cURL command (from browser dev tools: Network tab → Right-click → Copy as cURL).

Step 2: Extract Information

From the cURL command, extract:

URL: Full endpoint URL
Region: Extract from URL (e.g., us-east-1 from service.us-east-1.amazonaws.com)
Service name: Extract from authorization header SignedHeaders or URL (e.g., /us-east-1/q/aws4_request → "q")
Operation name: Extract from x-amz-target header (part after the dot, e.g., CreateAssignment from AmazonQDeveloperService.CreateAssignment)
Function name: Convert operation name to snake_case (e.g., CreateAssignment → create_assignment)
HTTP method: From -X flag or default to POST if --data present
Headers: Content-Type and x-amz-target (exclude authorization, cookie, user-agent, sec-*, origin, referer, priority)
Payload: From --data-raw or --data
Parameters: Extract keys from JSON payload

Step 3: Generate Python Code

Create a Python function following this pattern:

import boto3
import json
from botocore.awsrequest import AWSRequest
from botocore.auth import SigV4Auth
import requests


def function_name(param1, param2):
    """Call AWS API with description"""

    session = boto3.Session()
    credentials = session.get_credentials()

    payload = {
        "key1": param1,
        "key2": param2
    }

    request = AWSRequest(
        method="POST",
        url="https://service.region.amazonaws.com/",
        data=json.dumps(payload),
        headers={
            "Content-Type": "application/x-amz-json-1.0",
            "x-amz-target": "ServiceName.OperationName",
        },
    )

    SigV4Auth(credentials, "service-name", "region").add_auth(request)

    response = requests.post(request.url, headers=dict(request.headers), data=request.body)

    return response

Example

User provides cURL:

curl 'https://codewhisperer.us-east-1.amazonaws.com/' \
  -H 'authorization: AWS4-HMAC-SHA256 Credential=.../us-east-1/q/aws4_request, ...' \
  -H 'content-type: application/x-amz-json-1.0' \
  -H 'x-amz-target: AmazonQDeveloperService.CreateAssignment' \
  --data-raw '{"principalId":"123","principalType":"USER","subscriptionType":"Q_DEVELOPER_STANDALONE_PRO"}'

Auto-extracted:

Service: "q" (from authorization header: /us-east-1/q/aws4_request)
Region: "us-east-1" (from URL)
Operation: "CreateAssignment" (from x-amz-target)
Function name: "create_assignment" (snake_case of operation)
Parameters: principalId, principalType, subscriptionType (from payload)

Generated code:

import boto3
import json
from botocore.awsrequest import AWSRequest
from botocore.auth import SigV4Auth
import requests


def create_assignment(principal_id, principal_type="USER", subscription_type="Q_DEVELOPER_STANDALONE_PRO"):
    """Create Q Developer subscription assignment"""

    session = boto3.Session()
    credentials = session.get_credentials()

    payload = {
        "principalId": principal_id,
        "principalType": principal_type,
        "subscriptionType": subscription_type
    }

    request = AWSRequest(
        method="POST",
        url="https://codewhisperer.us-east-1.amazonaws.com/",
        data=json.dumps(payload),
        headers={
            "Content-Type": "application/x-amz-json-1.0",
            "x-amz-target": "AmazonQDeveloperService.CreateAssignment",
        },
    )

    SigV4Auth(credentials, "q", "us-east-1").add_auth(request)

    response = requests.post(request.url, headers=dict(request.headers), data=request.body)

    return response

Prerequisites

Generated code requires:

Python 3.6+
boto3: pip install boto3
requests: pip install requests
AWS credentials configured

aws-sigv4-req-builder

When & Why to Use This Skill

Use Cases