check_chain_exists

Verify if a specific grocery chain exists in the Kroger system by providing the chain name, returning a confirmation status for store availability checks.

Instructions

    Check if a chain exists in the Kroger system.
    
    Args:
        chain_name: Name of the chain to check
    
    Returns:
        Dictionary indicating whether the chain exists

Input Schema

TableJSON Schema

Name	Required	Description	Default
`chain_name`	Yes

Implementation Reference

src/kroger_mcp/tools/info_tools.py:108-143 (handler)

The handler function for the 'check_chain_exists' tool. It takes a chain_name parameter, uses get_client_credentials_client to get the API client, calls client.location.chain_exists(), and returns a success dict with existence status.

@mcp.tool()
async def check_chain_exists(
    chain_name: str,
    ctx: Context = None
) -> Dict[str, Any]:
    """
    Check if a chain exists in the Kroger system.
    
    Args:
        chain_name: Name of the chain to check
    
    Returns:
        Dictionary indicating whether the chain exists
    """
    if ctx:
        await ctx.info(f"Checking if chain '{chain_name}' exists")
    
    client = get_client_credentials_client()
    
    try:
        exists = client.location.chain_exists(chain_name)
        
        return {
            "success": True,
            "chain_name": chain_name,
            "exists": exists,
            "message": f"Chain '{chain_name}' {'exists' if exists else 'does not exist'}"
        }
        
    except Exception as e:
        if ctx:
            await ctx.error(f"Error checking chain existence: {str(e)}")
        return {
            "success": False,
            "error": str(e)
        }

src/kroger_mcp/server.py:75-75 (registration)
The line where the info_tools module's register_tools function is called on the MCP server instance, registering the check_chain_exists tool along with other info tools.
```
info_tools.register_tools(mcp)
```

src/kroger_mcp/tools/shared.py:25-53 (helper)

Helper function get_client_credentials_client() that provides the KrogerAPI client instance used in the handler for accessing public endpoints like chain_exists.

def get_client_credentials_client() -> KrogerAPI:
    """Get or create a client credentials authenticated client for public data"""
    global _client_credentials_client
    
    if _client_credentials_client is not None and _client_credentials_client.test_current_token():
        return _client_credentials_client
    
    _client_credentials_client = None
    
    try:
        load_and_validate_env(["KROGER_CLIENT_ID", "KROGER_CLIENT_SECRET"])
        _client_credentials_client = KrogerAPI()
        
        # Try to load existing token first
        token_file = ".kroger_token_client_product.compact.json"
        token_info = load_token(token_file)
        
        if token_info:
            # Test if the token is still valid
            _client_credentials_client.client.token_info = token_info
            if _client_credentials_client.test_current_token():
                # Token is valid, use it
                return _client_credentials_client
        
        # Token is invalid or not found, get a new one
        token_info = _client_credentials_client.authorization.get_token_with_client_credentials("product.compact")
        return _client_credentials_client
    except Exception as e:
        raise Exception(f"Failed to get client credentials: {str(e)}")

Kroger MCP Server