AWS Bedrock AgentCore vs Haystack: Which Agent Framework to Use?

AWS Bedrock AgentCore Bedrock AgentCore is AWS's managed runtime for production agents, launched in July 2025.

Haystack Haystack by deepset is a framework for building NLP and LLM pipelines.

Both wrap the same underlying agent pattern — an LLM call, a tool dispatch, a loop — in different abstractions. The choice between them is mostly about which mental model and ecosystem fits the team you have, not which one is technically more capable.

Pick AWS Bedrock AgentCore if agentCore is for production AWS deployments where you want to skip the runtime, memory, identity, and observability work and pay AWS to do it instead. It is framework-agnostic — bring Strands, LangGraph, CrewAI, or your own. For non-AWS teams, prototypes, or anything where you want to see what the agent is doing, plain Python on Lambda or a container is simpler. AWS Bedrock AgentCore is the right fit when the tradeoffs in its intro line up with how your team actually wants to work day-to-day; Haystack would force you to translate.

Pick Haystack if haystack earns its complexity when you're building RAG pipelines with multiple retrieval stages, document processing, and production deployment needs. But for straightforward agents with a few tools, the plain Python version is simpler to write and debug. Haystack is the right fit when the tradeoffs in its intro line up with how your team actually wants to work day-to-day; AWS Bedrock AgentCore would force you to translate.

Both AWS Bedrock AgentCore and Haystack pull in a class hierarchy and a dependency tree to wrap what is, at the core, an HTTP POST in a while loop. If your use case is straightforward — one provider, a handful of tools, a single agent — the framework cost may exceed the framework benefit. The lesson below shows the same pattern in ~60 lines without either dependency.