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FrameworksMulti-AgentArchitecture

Agentic AI Frameworks: A 2026 Comparison Guide

LangGraph, CrewAI, PydanticAI, AutoGen, OpenAI Agents SDK, and Strands — six frameworks, one decision. Here is how they actually differ on state, orchestration, and what happens when you take them to production.

AS
AgentSwarms Authors
June 30, 2026· 15 min read·
FrameworksMulti-AgentArchitecture

Every week, another agentic framework lands on Hacker News. Every week, a developer somewhere quietly rewrites their stack. This guide is the conversation you wish you'd had before that rewrite — what each framework is actually good at, where the seams show under load, and how to pick one without regretting it in three months.

We will compare six frameworks that cover the realistic shortlist in 2026: LangGraph, CrewAI, PydanticAI, AutoGen (now AG2), OpenAI Agents SDK, and AWS Strands Agents. The goal is not a feature checklist — every one of them can technically call a tool and loop. The goal is to surface the design choices behind each, because those choices are what you live with.

The three axes that actually matter

Skim a framework's README and you will see twenty differentiators. In production, three of them dominate everything else:

  • State management — where the agent's memory and intermediate results live, and whether you can resume a run after a crash or human approval without losing context.
  • Orchestration pattern — graph, role-based crew, conversation, or single-agent loop. This shapes how you reason about control flow and how easy multi-agent coordination becomes.
  • Production scalability — observability, retries, streaming, durable execution, and the blast radius when a tool call misbehaves.
Read this first

Pick on the axis that breaks you first. For most teams that is state management — the moment you add human-in-the-loop or long-running tools, frameworks without durable state become a liability overnight.

The comparison matrix

Here is the same six frameworks compared on the axes that matter, plus a few practical ones — type safety, multi-agent ergonomics, and lock-in risk.

Framework            State            Orchestration       Type safety   Multi-agent   Observability    Lock-in
─────────────────────────────────────────────────────────────────────────────────────────────────────────────────
LangGraph            Durable graph    Explicit DAG/loop   Good (TS/Py)  First-class   LangSmith        Medium
CrewAI               In-memory        Role-based crew     Light         First-class   Basic + OTel     Low
PydanticAI           In-memory        Single-agent loop   Excellent     Via graphs    Logfire (OTel)   Low
AutoGen / AG2        Conversation     Group chat          Light         First-class   Studio + OTel    Medium
OpenAI Agents SDK    Session store    Handoff graph       Good (Py/TS)  First-class   Traces UI        High (OAI)
AWS Strands Agents   Session + DDB    Single + multi      Good (TS/Py)  First-class   CloudWatch+OTel  High (AWS)
Short-term
Checkpointer (thread-scoped state)
Long-term
Store API (cross-thread, namespaced by user)
First-class persistent state; the production pick.
How each framework handles state. Durable graph state (LangGraph) survives crashes and approvals; conversation-based memory (AutoGen) is great for debate, painful for resuming work two days later.

State management: the thing that will bite you

LangGraph treats state as a typed dict that flows through a graph; checkpoints persist to Postgres, SQLite, or Redis so a graph paused for human approval at 2pm can resume at 9am the next morning with full context. This is the model that scales to enterprise workflows.

PydanticAI keeps state in a strongly-typed RunContext[Deps] that you pass through tool calls — the cleanest API of the bunch, but persistence is your problem. Pair it with Logfire and your own store if you need durability.

CrewAI and AutoGen lean on in-memory or conversation-history state. Fast to prototype, but a crashed worker takes the run with it. CrewAI Flows now adds checkpointing, which closes the gap for simpler cases.

OpenAI Agents SDK and AWS Strands offer first-party session stores (OpenAI's conversation store, Strands' DynamoDB session manager). Convenient until you want to leave the platform.

Orchestration patterns: pick the metaphor that fits your problem

  • Explicit graph (LangGraph, Strands graph mode) — best when control flow is non-trivial: conditional routing, loops, parallel branches, human gates. You write the graph, the framework runs it.
  • Role-based crew (CrewAI) — best when the problem decomposes into clear roles (researcher, writer, reviewer). Less code than a graph; less control when the roles need to disagree.
  • Group chat (AutoGen) — best for open-ended reasoning, debate, and red-teaming. Worst when you need predictable cost or latency.
  • Handoff graph (OpenAI Agents SDK) — agents transfer control to each other with structured handoffs. Clean mental model, tightly coupled to OpenAI's runtime.
  • Single-agent loop (PydanticAI, Strands single-agent) — best when one capable agent with good tools beats a committee. Often it does.
LangGraph
76%
Smolagents
73%
CrewAI
71%
AutoGen
68%

Task success rate (directional, from public benchmarks). The gap widens as tasks get harder — explicit state machines pull ahead when the path is long.

The same researcher → writer → reviewer pipeline run through three frameworks. As task difficulty climbs, success-rate divergence is driven by how the framework handles retries and partial failures, not raw model choice.

Production scalability: where the romance ends

A framework's prototype experience and its production experience are often two different products. Three things separate the ones that survive contact with real traffic:

  1. 1Durable execution — can a run survive a worker restart? LangGraph yes (checkpointer). Strands yes (session manager). CrewAI yes via Flows. PydanticAI / AutoGen / OpenAI Agents SDK — depends on how you wire it.
  2. 2Observability you did not have to build — LangSmith for LangGraph, Logfire for PydanticAI, OpenAI's traces UI, CloudWatch + OTel for Strands. CrewAI and AutoGen rely on OpenTelemetry exporters you configure yourself.
  3. 3Streaming and backpressure — every framework streams tokens; far fewer stream tool-call deltas cleanly. LangGraph and OpenAI Agents SDK lead here.
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22
LLM calls / task
5.5×
relative cost

AutoGen's conversational pattern can fire 20+ calls for the same job — roughly 5–6× the token bill of a tight LangGraph flow. Architecture is a budget decision.

Per-task cost across the same pipeline. The framework rarely changes token counts directly, but orchestration style does — group-chat patterns inflate cost on hard tasks because every turn pulls the full transcript into context.

Type safety and developer experience

PydanticAI is the standout — tools, dependencies, and outputs are all typed, with structured-output validation that turns model drift into a caught exception instead of a 3am bug report. LangGraph is close behind, with typed state and good TypeScript support. OpenAI Agents SDK ships Pydantic-validated handoffs. CrewAI and AutoGen are pleasant to write, lighter on types.

When to pick which

My priority is…
Reach for
LangGraph

an explicit state graph with checkpoints — you own every transition.

A blunt decision flow. Optimize for the first axis that breaks you — usually durability or type safety, not novelty.
  • LangGraph — production multi-agent systems with human approvals, long-running tools, or compliance requirements. Default pick when reliability matters.
  • CrewAI — fast prototypes, content pipelines, role-based decomposition. Ship a demo today; revisit when you need durability.
  • PydanticAI — Python teams that already love Pydantic, single-agent flows where correctness beats orchestration cleverness, anything with strict structured outputs.
  • AutoGen / AG2 — research, debate, red-teaming, code-generation loops where letting agents argue improves the answer.
  • OpenAI Agents SDK — you are all-in on OpenAI, want first-party traces, and value the cleanest handoff API on the market.
  • AWS Strands Agents — you are on AWS, want Bedrock-native deployment, and need session state that lives in your account.

The honest part

Frameworks matter less than people think. A well-designed agent in CrewAI will out-ship a sloppy one in LangGraph every time. Pick the framework whose mental model you can hold in your head at 11pm, and switch only when a concrete production constraint forces your hand. The good news: every framework on this list exports to portable patterns — graphs, tools, prompts — so a future migration is annoying but not fatal.

Try them all in one place

You can run the same agent through LangGraph, CrewAI, PydanticAI, AutoGen, OpenAI Agents SDK, and Strands inside AgentSwarms notebooks — same prompt, same tools, same model — and compare traces side-by-side. The fastest way to feel the differences this guide describes.


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