
The 11 Best AI Agent Frameworks in 2026 (with the 3 to Skip)
You don't always need a framework. But when you do, picking the wrong one costs months of refactoring, surprise LLM bills, and the kind of state-management bugs that ruin a sprint. Below are the 11 AI agent frameworks worth your time in 2026, plus 3 that keep showing up on "best of" lists they shouldn't. This is a developer survey, not a vendor list. We've shipped on five of these in client work, and we'll tell you which to skip on the first call.
Quick takeaways:
- Production winners: LangGraph, Claude Agent SDK, OpenAI Agents SDK, and Mastra (TypeScript) have the most named production deployments in 2026.
- Multi-agent prototypes: CrewAI for role-based crews; AG2 for research-grade conversation patterns. Both prototype fast, both cost more in LLM calls.
- No-framework option: A single LLM call with structured output handles roughly 40% of real "agent" tasks. Rule it out first.
- MCP support: LangGraph, OpenAI Agents SDK, Claude Agent SDK, Strands, Pydantic AI, and Mastra natively support the Model Context Protocol. The rest need shims.
TL;DR: The 11 AI Agent Frameworks at a Glance
The 11 best AI agent frameworks in 2026 are LangGraph, Claude Agent SDK, CrewAI, OpenAI Agents SDK, Mastra, Pydantic AI, Google ADK, AG2, LlamaIndex Agents, Strands Agents (with Bedrock AgentCore), and Smolagents. LangGraph leads for stateful production workflows. Mastra is the TypeScript pick. Claude Agent SDK is Anthropic-native. The rest fit specific stacks.
| Rank | Framework | Language | Best for | GitHub stars | MCP native | Production-ready | Skip if |
|---|---|---|---|---|---|---|---|
| 1 | LangGraph | Python (TS port) | Stateful, durable workflows | 24.8k | Yes | Yes (Klarna, Uber, LinkedIn) | TypeScript-first team |
| 2 | Claude Agent SDK | Python + TS | Anthropic-native (hooks, skills, MCP) | (Anthropic) | Yes | Yes (Claude Code itself) | Multi-provider build |
| 3 | CrewAI | Python | Role-based multi-agent prototypes | 44.3k | Shim | Yes (with care) | Need stateful loops / HITL |
| 4 | OpenAI Agents SDK | Python (TS) | OpenAI-native production runtime | 19k | Yes | Yes | Multi-provider build |
| 5 | Mastra | TypeScript | TS-first agents (Replit, PayPal) | 21.2k | Yes | Yes (150k weekly npm) | Python-default team |
| 6 | Pydantic AI | Python | Type-safe single-agent | (Pydantic) | Yes | Yes | Need orchestration |
| 7 | Google ADK | Python | GCP / Gemini stack | 17.8k | Partial | Yes | Not on GCP |
| 8 | AG2 (was AutoGen) | Python | Research-grade conversation patterns | 54.6k (combined) | Shim | Mixed | High-volume user-facing |
| 9 | LlamaIndex Agents | Python | RAG-grounded agents | (LlamaIndex) | Shim | Yes | Non-retrieval agents |
| 10 | Strands + AgentCore | Python | AWS-native (IAM/VPC/secrets) | (AWS) | Yes | Yes | Not on AWS |
| 11 | Smolagents | Python | Minimal, code-first execution | (HuggingFace) | Shim | No | Production / multi-agent |
Half this table is a function of your stack: pick the framework that lives where your auth, secrets, and infra already do. For the buyers narrowing between the top three, we have a head-to-head ship-speed test of LangGraph, CrewAI, and OpenAI Agents SDK that goes deeper than this listicle can.
Do You Even Need an AI Agent Framework?
Not always. Roughly 40% of production "agent" tasks are solved by a single LLM call with structured output (JSON mode or function calling). Frameworks earn their complexity when you need state across turns, deterministic retries, human approval steps, or multiple agents collaborating. If you have none of those, the OpenAI Responses API or raw function calling alone beats any framework on latency, debuggability, and bill.
Here's the test we use on every client call: can you draw your workflow as a flowchart with no loops and no branches? If yes, you don't need a framework. You need one well-typed function with a structured output schema. Classification, summarization, extraction, "rewrite this email in a friendlier tone": none of these need an agent runtime.
A framework starts paying for itself when:
- State has to survive across turns (a multi-step support flow, a research session)
- You need retries with backoff that don't lose context
- A human has to approve something mid-flow (the human-in-the-loop case)
- Two or more agents work together on different parts of the same job
- The workflow has to survive a process restart or a redeploy (durable execution)
If none of those apply, you're picking up a framework for vibes. We've talked roughly 40% of clients out of using one on the first call. The framework doesn't make the agent smarter. It manages complexity you don't have yet.
If you can draw your workflow as a flowchart with no loops or branches, you don't need a framework.
The 11 Best AI Agent Frameworks in 2026 (Ranked)
1. LangGraph: the production king
LangGraph is a stateful, graph-based orchestration framework from the LangChain team, GA at version 1.0 since October 2025. Best for production workflows that need durable execution, checkpointing, and human-in-the-loop steps. Used by Klarna, Uber, LinkedIn, BlackRock, and JPMorgan via LangGraph Platform.
What it actually does well. Durable execution that survives process restarts. Checkpoint-per-step state that you can replay and time-travel through. Native streaming. Human-in-the-loop via interrupt(). Python is the lead, with a TypeScript port that's solid but lags one or two minor versions.
Production signal. 24.8k GitHub stars, the LangGraph 1.0 GA announcement ships with named enterprise users, and the LangGraph Platform claims 400+ companies in production. In our experience, the checkpoint API is the single best thing about it. Debugging a multi-step agent gets dramatically less painful when you can rewind to step 4 and inspect what the model saw.
from langgraph.graph import StateGraph, END
graph = StateGraph(dict)
graph.add_node("plan", lambda s: {"plan": llm.invoke(s["goal"])})
graph.set_entry_point("plan")
graph.add_edge("plan", END)
agent = graph.compile()
agent.invoke({"goal": "draft a launch checklist"})Pick this if: You're shipping a multi-step agent to production and need state to survive process restarts. Skip this if: You're a TypeScript-only team. The TS port works, but Python gets every feature first.
State and checkpointing connect directly to memory design. If you're going further with LangGraph, our AI agent memory guide covers the patterns we ship most.
2. Claude Agent SDK: the SERP exclusive
The Claude Agent SDK is Anthropic's official framework for building agents on the same architecture that powers Claude Code: hooks, skills, subagents, and native MCP. Released late 2025, it's the only framework in this list where the vendor's flagship product is itself built on the SDK. That's the strongest production-readiness signal you can get.
What it actually does well. First-class Model Context Protocol support. Hooks for deterministic policy and safety logic (PreToolUse, PostToolUse, UserPromptSubmit). Skills for reusable agent capabilities. Subagents for parallel work without polluting the parent context. File-system-first context loading (CLAUDE.md, .claude/) that maps cleanly to how engineers already organize repos.
Production signal. Claude Code is the dogfood. Anthropic's own production product runs on this Claude Agent SDK, so every shipped feature in Claude Code is, by definition, a tested code path. None of the top 10 ranking listicles for this keyword include the Claude Agent SDK as of May 2026. That's the gap.
import { query } from "@anthropic-ai/claude-agent-sdk";
const result = query({
prompt: "List the top 3 files by line count in this repo",
options: { allowedTools: ["Bash", "Read"] },
});
for await (const msg of result) console.log(msg);Pick this if: You're building on Anthropic models and want hooks, skills, subagents, and MCP in one bundled SDK with the Claude Agent SDK. Skip this if: You need real multi-provider routing. The Claude Agent SDK is Claude-first by design, and that's a feature, not a bug, depending on your stack.
3. CrewAI: fastest multi-agent prototype
CrewAI is a Python framework for building role-based multi-agent crews. Each agent gets a goal, a backstory, and a toolset, and a Crew orchestrates them around a task. Best for fast multi-agent prototypes and content, research, or sales pipelines. 44.3k GitHub stars makes it the most-starred framework in this list.
What it actually does well. The role/goal/backstory abstraction maps cleanly to how non-engineers think about teams, which makes CrewAI an easy sell internally. Sequential and hierarchical processes are built-in. Tool ecosystem is broad.
Production signal. 44.3k stars, a large active community, and visible usage across research, content, and outbound-sales pipelines. We've shipped CrewAI in two client prototypes this year. Both converted into "great demo, now please rebuild on LangGraph" within six weeks once we needed real state management.
from crewai import Agent, Task, Crew
researcher = Agent(role="Researcher", goal="Find sources", backstory="...")
writer = Agent(role="Writer", goal="Draft post", backstory="...")
task = Task(description="Summarize X", agent=writer)
Crew(agents=[researcher, writer], tasks=[task]).kickoff()Pick this if: You need a working multi-agent prototype this week, not in two sprints. Skip this if: Your workflow has real loops or human-in-the-loop steps. CrewAI's stateful story is weaker than LangGraph's, which we cover in our head-to-head with LangGraph.
4. OpenAI Agents SDK: the production-GA successor to Swarm
The OpenAI Agents SDK is OpenAI's production-GA agent framework (the successor to the experimental Swarm). It builds on the Responses API runtime with native MCP support, parallel tool calls, and a "handoffs" primitive for agent-to-agent transfer. Best for teams committed to OpenAI as their primary model provider.
What it actually does well. Tight Responses API integration: sessions, tool calls, and tracing come for free. MCP support is first-class on both the server and client side. The handoffs primitive is the cleanest abstraction for "let agent A pass control to agent B" that any framework offers today.
Production signal. 19k GitHub stars. The official Agents SDK docs include benchmarking and tracing examples. Fewer named enterprise users than LangGraph or Mastra publish, but OpenAI's own Realtime and Assistants products use the same primitives.
from agents import Agent, Runner
agent = Agent(name="Helper", instructions="Answer concisely.")
result = Runner.run_sync(agent, "What is MCP?")
print(result.final_output)Pick this if: Your stack is OpenAI-first and you want OpenAI's own opinion on agent architecture. Skip this if: You're routing across providers and need provider-agnostic primitives.
5. Mastra: the TypeScript leader
Mastra is a TypeScript-first agent framework with 21.2k GitHub stars and roughly 150k weekly npm downloads, which makes it the de facto TypeScript leader for AI agents in 2026. Used in production by Replit, PayPal, and Adobe. Native MCP support, integrated evals, and a workflows primitive that handles state cleanly.
What it actually does well. TypeScript native, not a port. Evals are built into the framework, so you don't bolt on a separate library to grade your agent's output. The workflows primitive is genuinely good (closer to LangGraph than to CrewAI in design). MCP support is first-class.
Production signal. 150k weekly npm downloads. Named enterprise users (Replit, PayPal, Adobe) on the Mastra GitHub repo. For Next.js shops that don't want to run a Python sidecar just for the agent layer, this is the answer.
import { Agent } from "@mastra/core";
import { openai } from "@ai-sdk/openai";
const agent = new Agent({
name: "support",
model: openai("gpt-4o"),
instructions: "Be concise.",
});
await agent.generate("Refund policy?");Pick this if: Your team is TypeScript-first and shipping a Next.js or Node app. Mastra is the closest thing to a Python-quality agent framework in the TS ecosystem. Skip this if: You're Python-default. You'll fight the ecosystem for no real gain.
6. Pydantic AI: type-safe, single-agent
Pydantic AI is the Pydantic team's agent framework, built around their type-validation library. Best for type-safe, single-agent Python applications where you want responses validated as Pydantic models. Strong MCP support and a clean async API.
What it actually does well. Type safety end-to-end: your agent's outputs are validated as Pydantic models, which means the rest of your codebase keeps its type guarantees. Async-native. Testing is straightforward because you can mock the model with a typed response. MCP support landed in 2025.
Production signal. Backed by the Pydantic team, used by teams who already standardize on Pydantic for data validation. See our Pydantic AI deep dive for production patterns.
from pydantic_ai import Agent
agent = Agent("openai:gpt-4o", system_prompt="Be concise.")
result = agent.run_sync("Top 3 Python web frameworks?")
print(result.output)Pick this if: You already love Pydantic and want a small, focused single-agent framework that won't fight your type checker. Skip this if: Your agent needs to grow into a multi-agent or heavily stateful system. Pydantic AI deliberately stays narrow.
7. Google ADK: the GCP play
Google ADK (Agent Development Kit) is Google's open-source agent framework, optimized for Gemini models and Vertex AI Agent Engine. 17.8k GitHub stars. Strong for teams running on Google Cloud who want first-class Gemini multimodality and a managed runtime path.
What it actually does well. Tight Gemini and Vertex AI integration. Multimodal-native: image, audio, and video as first-class inputs without bolt-on libraries. Multi-agent and tool primitives are reasonable. MCP support is partial and evolving.
Production signal. 17.8k GitHub stars, and a clean upgrade path to managed Vertex AI Agent Engine. Inside the Google stack, ADK is the obvious pick. Outside it, the value drops fast. For a hands-on start, see our Google ADK tutorial.
from google.adk.agents import Agent
agent = Agent(
name="helper",
model="gemini-2.0-flash",
instructions="Be concise.",
)
agent.run("What is Vertex AI?")Pick this if: You're on GCP and Gemini is your primary model. Skip this if: You're not on GCP. The value collapses outside the Google stack.
8. AG2 (formerly AutoGen): multi-agent conversation research
AG2 is the community-led continuation of Microsoft's original AutoGen project: a multi-agent conversation framework focused on group chat, debate, and complex role assignment. 54.6k combined stars across the original and AG2 forks. Best for research-grade multi-agent patterns and academic adoption.
What it actually does well. GroupChat patterns. Complex role and permission setups. Strong academic use, including agent-debate and reflection-loop research. If your workflow genuinely benefits from agents critiquing each other, AG2 has the most-mature primitives.
The fork, briefly. The active community moved to ag2ai/ag2 after the 2024 governance split. Microsoft's microsoft/autogen keeps shipping separately, but PR velocity, ecosystem packages, and new features lean toward AG2. Start new projects on AG2 unless you have a specific Microsoft-stack reason not to.
Cost caveat. A 4-agent GroupChat × 5 rounds is roughly 20 LLM calls per task. Multiply that by daily volume and the bill stops being academic.
from autogen import ConversableAgent, GroupChat, GroupChatManager
a = ConversableAgent("planner", llm_config={"model": "gpt-4o"})
b = ConversableAgent("critic", llm_config={"model": "gpt-4o"})
chat = GroupChat(agents=[a, b], messages=[], max_round=5)
mgr = GroupChatManager(groupchat=chat)
a.initiate_chat(mgr, message="Plan a launch checklist.")Pick this if: Your workflow genuinely benefits from agents debating or critiquing each other (reasoning chains, research pipelines). Skip this if: You're shipping a high-volume customer-facing product. LLM call costs scale brutally with GroupChat rounds.
9. LlamaIndex Agents: for retrieval-grounded agents
LlamaIndex Agents extends the LlamaIndex retrieval ecosystem with agent workflows: agents that read, reason over, and act on indexed knowledge. Best for RAG-first applications where the agent is mostly a smart query layer over a corpus.
What it actually does well. Best-in-class retrieval primitives: document loaders, vector indexes, query engines, reranking. The newer workflows API gives you agent-style control flow on top of those retrieval primitives. If your agent's main job is "read the docs, answer the question," this is the framework that takes retrieval seriously.
Production signal. Deep ecosystem of loaders and indexes. Heavy adoption in enterprise RAG and document-Q&A use cases.
from llama_index.core.agent.workflow import AgentWorkflow
from llama_index.core import VectorStoreIndex, SimpleDirectoryReader
index = VectorStoreIndex.from_documents(SimpleDirectoryReader("./docs").load_data())
agent = AgentWorkflow.from_tools_or_functions([index.as_query_engine()])
await agent.run(user_msg="Summarize the onboarding doc.")Pick this if: Your agent's main job is to read documents and answer questions: retrieval is the core, agency is the wrapper. Skip this if: You don't have a meaningful knowledge corpus. A retrieval-heavy framework on no documents is overkill.
10. Strands Agents + Bedrock AgentCore: the AWS exclusive
Strands Agents is AWS's open-source Python SDK for building agents, paired with Bedrock AgentCore for managed runtime (GA late 2025, with major April, May 2026 updates). The AWS-native choice: agents inherit IAM, VPC, secrets, and CloudWatch logs without bolt-ons. Like the Claude Agent SDK, none of the top 10 listicles for this query include Strands Agents as of May 2026.
What it actually does well. Model-agnostic at the SDK level (Bedrock, Anthropic, OpenAI). IAM and VPC inheritance through AgentCore means your agent runs inside your existing AWS security posture, with no separate auth layer and no secrets-management rewrite. CloudWatch observability for free. MCP support is first-class.
Production signal. Backed by AWS, with Bedrock AgentCore shipping enterprise features (long-term memory, gateway, identity, observability) on a roughly monthly cadence in 2026. Every AWS-shop client we've talked to in Q1 2026 has asked about this. The SERP doesn't reflect that demand yet.
from strands import Agent
from strands.models import BedrockModel
agent = Agent(
model=BedrockModel(model_id="anthropic.claude-sonnet-4-20250514"),
system_prompt="Answer concisely.",
)
agent("What's an IAM role?")Pick this if: You're already on AWS and want your agents inside your VPC with your IAM policies and your CloudWatch dashboards. Skip this if: You're not on AWS or you're optimizing for portability across clouds.
11. Smolagents: the minimalist
Smolagents is Hugging Face's minimalist agent framework, designed around "code agents": the agent writes Python code which is then executed in a sandbox, instead of structured tool calls. Best for one-off scripts, research, or teams that prefer a single ~1k-line library they can read end-to-end.
What it actually does well. Tiny codebase you can actually read in an afternoon. That's not a marketing line, it's the value prop. The code-agent paradigm (model writes code, sandbox executes) is genuinely different from the structured-tool-call paradigm everyone else uses. HF ecosystem integration is clean.
Production signal. Strong research and tinkering adoption. Not a fit for production multi-agent systems. Smolagents is a craft tool.
from smolagents import CodeAgent, InferenceClientModel
agent = CodeAgent(tools=[], model=InferenceClientModel())
agent.run("How many seconds in a non-leap year?")Pick this if: You want a framework you can fully understand in an afternoon, or you're using code-agents intentionally. Skip this if: You're shipping multi-agent production. Smolagents is a craft tool, not a workhorse.
The 3 AI Agent Frameworks to Skip in 2026
Three frameworks frequently named in "best AI agent frameworks" lists don't deserve a slot in 2026: Rasa (legacy chatbot framing, not LLM-agent-native), the original Microsoft AutoGen v0.2 (superseded; the active community is on AG2), and Lindy (a no-code product, not a framework, so it doesn't belong in a frameworks comparison at all).
This isn't a hit piece on any of them. Each had a legitimate moment. The reasons they're off the list are specific.
Rasa
Rasa was built for intent/entity chatbots: the NLU world that predates tool-calling LLMs. Its 2026 LLM integrations work, but they feel bolted onto an architecture that was designed for a different problem. If you're starting fresh in 2026 and you need a real LLM agent, you'll get there faster on any of the 11 frameworks above. Rasa still has legitimate use cases for teams maintaining classical NLU pipelines. It just isn't the right starting point for new agent work.
Original Microsoft AutoGen (v0.2)
Microsoft's microsoft/autogen repo keeps shipping. The community velocity, the new examples, and the ecosystem packages live on the AG2 fork (ag2ai/ag2) after the 2024 governance split. Both still receive updates. If you're starting a new multi-agent conversation project, start on AG2. That's where the maintainer attention is. We covered the difference in the AG2 section above; this isn't a knock on the underlying ideas, just a "follow the active community" call.
Lindy
Lindy is a fine no-code workflow product. It is not a framework. There's no SDK to import, no agent class to inherit from, no graph or workflow primitive you compose in code. Including it in a "best AI agent frameworks" list (as Lindy itself does, ranking itself #1) is a category error. If you want a no-code agent builder, evaluate Lindy alongside Zapier Central, n8n, and Gumloop. Don't evaluate it alongside LangGraph.
Including a no-code product in a frameworks comparison is a category error. And yes, that's exactly what Lindy did when it ranked itself #1.
AI Agent Framework Decision Matrix: Which One for Your Stack?
Pick your AI agent framework by stack first, use case second: Python production = LangGraph; TypeScript = Mastra; Anthropic-native = Claude Agent SDK; OpenAI-native = OpenAI Agents SDK; AWS = Strands + AgentCore; GCP = Google ADK; multi-agent prototype = CrewAI; retrieval-grounded = LlamaIndex Agents; type-safe single-agent = Pydantic AI; research-grade group chat = AG2.
| Your situation | Pick this | Why |
|---|---|---|
| Python production, stateful, durable | LangGraph | Checkpointing + HITL + named enterprise users |
| TypeScript / Next.js app | Mastra | Real TS-native, evals built-in, MCP support |
| Anthropic / Claude stack | Claude Agent SDK | Hooks + skills + subagents bundled, dogfooded by Claude Code |
| OpenAI-only stack | OpenAI Agents SDK | Responses API runtime, MCP-native, handoffs |
| AWS / Bedrock | Strands + AgentCore | IAM, VPC, secrets, and CloudWatch inheritance |
| GCP / Gemini | Google ADK | First-class Gemini multimodality |
| Multi-agent prototype, fast | CrewAI | Role/goal/backstory abstraction is fastest to grok |
| Research-grade multi-agent debate | AG2 | GroupChat patterns, academic adoption |
| RAG-first agent | LlamaIndex Agents | Retrieval is the core |
| Single agent, type-safe | Pydantic AI | Pydantic-validated outputs |
| Tiny framework you can read in a day | Smolagents | Roughly 1k LOC, code-agent paradigm |
One thing to notice: most of this table is about your stack, not the agent. That's deliberate. The framework that "fits" is almost always the one that lives where your auth, logging, secrets, and deployment already do. Anything else is friction you'll feel three months in.
MCP Support Across AI Agent Frameworks
Six of the 11 frameworks here natively support the Model Context Protocol in 2026: LangGraph, Claude Agent SDK, OpenAI Agents SDK, Mastra, Pydantic AI, and Strands. The rest (CrewAI, AG2, LlamaIndex Agents, Google ADK, and Smolagents) work with MCP only via community shims or adapter packages.
| Framework | MCP native? | Notes |
|---|---|---|
| LangGraph | Yes | MCP tool nodes built-in |
| Claude Agent SDK | Yes | MCP is the canonical tool interface |
| CrewAI | Shim | Community packages (e.g., crewai-tools MCP adapter) |
| OpenAI Agents SDK | Yes | First-class MCP server and client primitives |
| Mastra | Yes | Native MCP integration |
| Pydantic AI | Yes | MCP support added in 2025 |
| Google ADK | Partial | MCP support evolving (check current docs) |
| AG2 | Shim | Community MCP integration |
| LlamaIndex Agents | Shim | Use llama-index-tools-mcp |
| Strands Agents | Yes | First-class via Strands tools |
| Smolagents | Shim | Community examples |
Why does this matter? MCP is the 2026 lingua franca for tools. If you build an MCP server for your internal CRM, you want every agent across every team to be able to call it without rewriting a custom integration per framework. Native support means the framework handles the protocol for you. Shims mean you maintain glue code that breaks every few releases.
If MCP isn't on your framework's roadmap in 2026, your framework isn't on your roadmap for 2027.
How We Picked These AI Agent Frameworks
These rankings reflect four criteria, applied in order:
- Production deployments. Named enterprise users matter more than star counts. Klarna, Uber, LinkedIn, BlackRock, and JPMorgan on LangGraph. Replit, PayPal, and Adobe on Mastra. Claude Code itself on the Claude Agent SDK. Where we couldn't find named users, the framework dropped.
- Community velocity. GitHub stars are a noisy signal, but PR cadence and last-meaningful-release dates aren't. We checked every repo within a week of writing. A framework with 50k stars and no release in eight months is a worse bet than a 17k-star repo shipping every two weeks.
- MCP support. We treat the Model Context Protocol as a 2026 must-have. Frameworks with native support got the edge over those needing shims.
- Hands-on usage. We've shipped agents on LangGraph, CrewAI, OpenAI Agents SDK, Claude Agent SDK, and Mastra in client projects this year. For Pydantic AI, Google ADK, AG2, LlamaIndex, Strands, and Smolagents, we've built proofs of concept but not always shipped production. Every verdict above marks the difference.
What we didn't do: invent benchmark numbers. You'll see plenty of listicles quoting latency comparisons that don't reproduce. We'd rather tell you "we evaluated this for two weeks" than make up a number.
Frequently Asked Questions
What is the best AI agent framework in 2026?
For production Python workloads, LangGraph (24.8k stars, durable execution, named enterprise users like Klarna and Uber). For TypeScript, Mastra. For Anthropic-native builds, the Claude Agent SDK. There is no single "best." The right answer depends on your stack, model provider, and whether you need state across turns or just a smart function.
Is LangChain still relevant in 2026?
LangChain itself has been largely superseded by LangGraph for agent workflows. The LangChain team's own recommendation is LangGraph for anything stateful. LangChain still has value as a model/loader/retriever abstraction layer, and large existing projects use it daily. But if you're starting a new agent project in 2026, start on LangGraph and skip LangChain core.
Is the Claude Agent SDK actually production-ready?
Yes. The strongest evidence is that Anthropic's own product, Claude Code, is built on the SDK. That's the same vendor-dogfood signal that made the OpenAI Agents SDK trustworthy when it succeeded Swarm. Caveats: it's Anthropic-first by design, so multi-provider builds will fight it. For Claude-native agents, nothing else comes close right now.
What's the difference between AG2 and AutoGen?
AG2 (ag2ai/ag2) is the community-led continuation of Microsoft's original AutoGen project after a 2024 governance split. Microsoft's microsoft/autogen still ships, but the active community, PRs, and ecosystem velocity shifted to AG2. Start new projects on AG2 unless you have a specific Microsoft-stack reason. Both still receive updates; we recommend AG2 for new work.
Which AI agent framework is best for production?
LangGraph (Python) and Mastra (TypeScript) have the most named production deployments in 2026: Klarna, Uber, LinkedIn on LangGraph; Replit, PayPal, Adobe on Mastra. The Claude Agent SDK and OpenAI Agents SDK are also production-ready, but tie you to their respective model providers. Strands + AgentCore is the AWS-native pick when infrastructure inheritance matters more than portability.
Which AI agent framework is best for TypeScript?
Mastra. Native TypeScript (not a port), 21.2k GitHub stars, roughly 150k weekly npm downloads, integrated evals, MCP support, and named users including Replit, PayPal, and Adobe. The Vercel AI SDK is also TS-first and excellent for streaming UI, but Mastra has the deeper agent abstraction: workflows, evals, and durable state out of the box.
Do I need a framework, or can I just call the LLM API?
Often you don't. A single LLM call with structured output handles classification, summarization, and extraction. Function calling handles single-tool single-turn agents. You need a framework when you have state across turns, retries with backoff, human approval steps, or multiple agents working together. Rule out the no-framework path first: it ships faster and debugs easier.
Are any of these AI agent frameworks free?
All 11 frameworks in this list are open source (Apache 2.0 or MIT licenses). The paid layer comes from optional managed runtimes: LangGraph Platform, Bedrock AgentCore, Vertex AI Agent Engine, and Mastra Cloud. You can run any of these frameworks fully self-hosted on your own infrastructure for free. The "Claude Agent SDK" is free; you pay for Claude API usage as normal.
Honest Take: How Techsy Picks AI Agent Frameworks for Client Projects
A short, opinionated note from us. Most clients arrive thinking they need an agent framework. Most don't, at least not on day one. Here's how we actually decide:
- Stack alignment first. Python or TypeScript. AWS or GCP or neither. Anthropic, OpenAI, or both. The framework that lives where your existing infrastructure does will save you more time than any clever feature.
- MCP-native preferred. Tools we build today should be portable to tools we build next year. That means native MCP support over shims.
- Default picks. We ship LangGraph and the Claude Agent SDK most often, with Mastra for TypeScript-heavy clients. For OpenAI shops committed to the platform, the OpenAI Agents SDK is the cleanest pick.
When we tell clients to skip a framework entirely, it's because a single LLM call with structured output handles the actual job. That's roughly 40% of first conversations. Saying "you don't need this yet" loses us short-term revenue and earns us the next three projects.
Building an agent and want a second opinion on framework choice? Our AI agent development services page covers how we work, and a Get a free consultation call is the fastest way to figure out whether you need a framework at all.
Conclusion
Three things to take away. Pick by stack first (Python vs TypeScript, AWS vs GCP, OpenAI vs Anthropic) and let use case decide between options inside your stack, not across it. Rule out the no-framework path before adding framework complexity; 40% of "agent" tasks are a single structured-output call. And MCP support is the 2026 portability bet: frameworks without it will lose ecosystem reach by 2027.
If you'd like a second pair of eyes on your build, Get a free consultation and we'll tell you which of the 11 above (or none of them) actually fits your job.
The Techsy editorial team ships AI agent systems for clients across the LLM, fintech, and dev-tools spaces. We've built on LangGraph, CrewAI, OpenAI Agents SDK, Claude Agent SDK, and Mastra in real production work. The verdicts here reflect what we'd recommend to a colleague, not what a vendor paid us to say.