Mastra Alternatives in 2026: Vercel AI SDK, LangGraph.js, OpenAI Agents SDK, and 7 More Compared

Vercel AI SDK 7: the default when you leave Mastra

Most of what a Mastra agent does is a loop. Call the model, run the tool it asked for, feed the result back, stop when it is done. The AI SDK's ToolLoopAgent is that loop, with stopWhen and prepareStep for controlling it, and nothing else attached.

That is the appeal and the problem. The AI SDK docs describe workflows as patterns you assemble from generateText and ordinary control flow, and they point to Vercel's separate eve framework for durable, long-running agents. Memory is not in the docs at all. So you bring your own. For a support bot that answers in one request, you will never notice. For an agent that waits two days for a refund approval, you will need Inngest steps or a Cloudflare Durable Object underneath it.

The migration is gentler than people expect. Mastra agents accept AI SDK model instances, so your provider setup and your Zod tool schemas move across with light edits. What does not move is Mastra's workflow engine. Rewrite those as Inngest functions and keep each step.run small.

LangGraph.js: when the workflow is the product

LangGraph.js was downloaded more than Mastra last week, 4.88 million times to 3.15 million. That surprised us. It also tells you the TypeScript port is no longer a side project.

Pick it when you can draw your agent as a state machine and the arrows matter. A loan-review agent that drafts, pauses for an underwriter, resumes with their edits, and retries a failed credit pull from the last checkpoint is the textbook case. LangGraph's checkpointers and interrupts handle that natively. Mastra workflows can suspend and resume too, but in LangGraph the checkpoint is the center of the design rather than a feature you reach for.

The cost is code volume and LangSmith. Plus is $39 per seat per month, so a ten-person team pays $390 before overage just to see traces. You can skip LangSmith and export OpenTelemetry elsewhere, though most teams don't. Our full head-to-head is in Mastra vs LangGraph.

OpenAI Agents SDK: good if you already live on OpenAI

The JS SDK covers agents, handoffs, guardrails, sessions, and a realtime voice stack with WebRTC and WebSocket transports. It is the strongest voice option on this list. It can call other vendors' models through the AI SDK adapter in @openai/agents-extensions, but the tracing exporter and the dashboard it feeds are OpenAI's, and the package is still at 0.21.0. We would not build a multi-vendor product on it yet.

Claude Agent SDK

If your "agent" mostly works inside a repository, running commands and editing code, use the harness that already does that well instead of rebuilding Claude Code's loop on top of Mastra.

Cloudflare Agents SDK: every agent is a Durable Object

Each agent instance gets its own SQL storage and survives eviction, with scheduling and WebSockets built in. For per-user agents that sleep for days and wake on a cron, this is the cheapest durable home we have priced: the Workers Paid plan starts at $5 a month. The lock-in is total, though. You are writing for Workers, and there is no running it on Fly.io later.

VoltAgent and Inngest AgentKit: the smaller bets

VoltAgent looks the most like Mastra. Agents, workflows, memory, a hosted console. If your team likes Mastra's model and dislikes its pricing, VoltOps Core at $50 a month for 50,000 traces is the honest comparison, and the code will feel familiar within an afternoon. At 53,000 weekly downloads, though, you will be reading source more often than Stack Overflow.

AgentKit is interesting for a different reason. It runs agent networks on Inngest's step engine, so retries and durability come free. It is pre-1.0 and only makes sense if Inngest is already in your stack; our Temporal vs Inngest vs Trigger.dev vs BullMQ review covers that choice.

Python teams: PydanticAI first, CrewAI second

If your model code already lives in Python, a TypeScript framework is the wrong tool. PydanticAI is our pick there because validated, typed outputs fix the failures that actually page people (a malformed JSON field at 2 a.m.). CrewAI is faster to demo and harder to debug once a role-based crew starts disagreeing with itself in production.

Where each option fits (and where it does not)

• Mastra fits a TypeScript team that uses workflows, memory, evals, and Studio together. It does not fit if you only use the agent loop, because you are carrying a framework for one feature. Self-hosting the Apache 2.0 code removes the Mastra Platform bill entirely, which is the first thing to try before switching.
• Vercel AI SDK 7 fits product teams shipping chat and tool-calling inside a Next.js or Node app. It does not fit agents that must pause for hours without a durable runner underneath.
• LangGraph.js fits checkpointed, human-in-the-loop workflows and teams with a Python LangGraph twin. It does not fit a three-person startup that wants to ship this week.
• OpenAI Agents SDK fits OpenAI-only stacks and voice. It does not fit a multi-vendor model strategy.
• Cloudflare Agents fits per-user, long-lived agents on Workers. It does not fit if you might leave Cloudflare.
• VoltAgent fits teams that want Mastra's design at a $50 observability bill. It does not fit risk-averse buyers who need a large community.
• PydanticAI fits Python backends. Not Next.js shops.

Mastra still wins one comparison outright: the time from npm create mastra to a working agent with memory and a local playground. Nobody else on this list beats it. If that is what your team values most, the answer to "mastra alternatives" may be to self-host Mastra and stop paying for the platform.

For a wider, older survey that also covers Semantic Kernel, see our best Mastra alternatives roundup. For prompt versioning across any of these frameworks, see prompt management tools for developers.

Mastra alternatives FAQ

What is the best Mastra alternative in 2026?

For a TypeScript team, the Vercel AI SDK (version 7, using its ToolLoopAgent class) paired with a durable runner such as Inngest or Cloudflare Agents. It keeps the same provider packages Mastra already accepts and has no platform fee. If you need graph-shaped workflows with checkpoints and human approval in the middle of a run, choose LangGraph.js instead. Python teams should look at PydanticAI.

Is Mastra free?

The framework is. Mastra is open source under Apache 2.0 and you can self-host it at no cost. Mastra Platform, the hosted product, has a $0 Starter plan and a $250 a month Teams plan, and a persistent server with 24/7 uptime costs $100 per project on either plan, per mastra.ai/pricing checked November 7, 2026.

Is LangGraph.js more popular than Mastra?

By npm downloads, yes. In the week of October 31 to November 6, 2026, @langchain/langgraph was downloaded about 4.88 million times and @mastra/core about 3.15 million times, according to the npm downloads API. Downloads include CI installs and transitive dependencies, so treat them as a rough adoption signal.

Can the OpenAI Agents SDK use Claude or Gemini models?

Yes, through its model provider interface and the AI SDK integration in the @openai/agents-extensions package. The SDK is still pre-1.0 (version 0.21.0 on npm in November 2026), and its tracing exporter targets OpenAI's dashboard, so teams on other model vendors usually get less out of it.

What is the closest drop-in replacement for Mastra?

VoltAgent. It is a TypeScript framework (MIT, version 2.11.1) with agents, workflows, memory, and a hosted observability console called VoltOps, which starts at $50 a month for 50,000 traces. It is much smaller than Mastra, at about 53,000 weekly npm downloads.