AWS Bedrock Agents (Classic) vs. Bedrock AgentCore — What’s the Difference?

AWS has rebranded its original Bedrock Agents service as 'Classic' and is moving it into maintenance mode, closed to new customers after July 30, 2026, while introducing Bedrock AgentCore, a modular infrastructure platform that lets developers bring their own agent code and control orchestration. AgentCore, launched in preview May 2026 and GA June 2026, offers 12 components including persistent memory, a tool gateway with OAuth, and native observability, whereas Classic provides a fully managed, opinionated service with AWS-controlled orchestration and session-scoped memory. The shift means teams needing custom orchestration, multi-agent systems, or non-Bedrock models should adopt AgentCore, while those with simple, working setups can stay on Classic.

If you’re building on AWS Bedrock, there’s a big shift happening in how agents get built. Here’s the breakdown. 𝗧𝗵𝗲 𝗢𝗻𝗲-𝗟𝗶𝗻𝗲𝗿 → Bedrock Agents Classic : a fully managed, opinionated agent service. AWS controls the orchestration loop. → Bedrock AgentCore: a modular infrastructure platform. You bring your own agent code and control the orchestration loop yourself. 𝗕𝗲𝗱𝗿𝗼𝗰𝗸 𝗔𝗴𝗲𝗻𝘁𝘀 𝗖𝗹𝗮𝘀𝘀𝗶𝗰 Launched November 2023, now rebranded “Classic” and moving into maintenance mode — closed to new customers after July 30, 2026. What you get: AWS-managed ReAct-style orchestration loop Action Groups OpenAPI schemas or Lambda functions for tool calls Built-in RAG via Knowledge Bases Managed session memory short-term, within a conversation Launched in preview May 2026, GA June 2026 — this is AWS’s forward direction for agent infrastructure. You bring your own agent code — any framework: Strands Agents, LangGraph, CrewAI, LlamaIndex, or a fully custom build — and AgentCore supplies the surrounding infrastructure through 12 components: Runtime — deploys your agent in serverless, session-isolated containers with auto-scaling Harness — an optional thin orchestration layer if you want AWS to manage the loop Memory — persistent, long-term state across sessions not just session-scoped Gateway — managed tool connectivity with auth and rate limiting Identity — OAuth2/OIDC auth for tools, with token refresh and per-user permissions Code Interpreter — sandboxed code execution Browser — web browsing capability Observability — real-time tracing, logging, and metrics Payments — support for agent-initiated transactions Evaluations — testing and scoring against datasets Policy — guardrails and access control Registry — a catalog for discovering and reusing agents 𝗞𝗲𝘆 𝗗𝗶𝗳𝗳𝗲𝗿𝗲𝗻𝗰𝗲𝘀 𝗮𝘁 𝗮 𝗚𝗹𝗮𝗻𝗰𝗲 Philosophy: Classic handles everything for you. AgentCore hands you the infrastructure and lets you own the agent logic. Orchestration: Classic is fixed and AWS-managed. AgentCore is fully yours to write, in any framework. Models: Classic is Bedrock-only. AgentCore supports any model, any provider. Memory: Classic is session-scoped. AgentCore is persistent and cross-session. Tools: Classic uses Action Groups. AgentCore uses a Gateway with managed OAuth and rate limiting. Multi-agent: Limited in Classic. First-class in AgentCore. Observability: Classic relies on CloudWatch. AgentCore has a dedicated tracing and metrics component. Evaluation: Not built into Classic. Native in AgentCore. Learning curve: Classic — about 30 minutes to a first agent. AgentCore — steeper, since you need to understand each component. Status: Classic is entering maintenance mode. AgentCore is under active development and now GA. 𝗪𝗵𝗲𝗻 𝘁𝗼 𝗨𝘀𝗲 𝗪𝗵𝗮𝘁 Bedrock Agents Classic fits best when: The current setup is already working well The flow is simple: prompt → tool calls → response No custom orchestration logic is needed Bedrock-only models are sufficient Zero infrastructure management is the priority AgentCore fits best when: Custom orchestration or multi-step planning is required Non-Bedrock models, or a mix of models, are needed The system involves multiple agents Persistent memory across sessions is required Fine-grained, per-user tool authentication is needed A framework like LangGraph, CrewAI, or Strands is in use Production-grade observability and evaluations are required The deployment is for enterprise use with VPC/PrivateLink requirements 𝗧𝗵𝗲 𝗧𝗮𝗸𝗲𝗮𝘄𝗮𝘆 Bedrock Agents Classic was AWS’s “easy button” for agents. AgentCore is the platform for teams that have outgrown that button and want real control over orchestration, memory, and infrastructure — without giving up managed deployment, observability, and security.