Yes it is that simple to connect to AWS Bedrock directly from Snowflake without the need for snowflake external function or API Gateway.
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Overview of AWS Bedrock
Amazon Bedrock is a fully managed service that offers a choice of high-performing foundation models (FMs) from leading AI companies like AI21 Labs, Anthropic, Cohere, Meta, Stability AI, and Amazon with a single API, along with a broad set of capabilities you need to build generative AI applications, simplifying development while maintaining privacy and security.
Amazon Bedrock is serverless, you don’t have to manage any infrastructure