There is a version of this question that has a clean answer, and it is not the one people type into a search box. They type "vercel ai sdk vs langgraph" wanting a winner. What they have is a fork between two philosophies of how much of an agent you want to build yourself — and after AI SDK 7 shipped on June 25, 2026, that fork got sharper, not blurrier.
What each one became#
For years the Vercel AI SDK was a model wrapper — a tidy way to call an LLM and stream tokens into a React app. AI SDK 7 ended that framing. Vercel now describes it as the foundation for "agents and AI platforms in production," and the release is built around three things that were previously your problem: approvals, durability, and telemetry. It also went multimodal — text, audio, real-time, image, video — but the agent story is the point.
That story ships as three primitives:
- ToolLoopAgent — the classic tool-calling loop with configurable stop conditions and typed runtime context. This is the default agent most people want.
- WorkflowAgent — makes each tool execution a durable, automatically retried step via Vercel's Workflow SDK. An agent that survives a deploy or a crash mid-run, without you writing the checkpoint logic.
- HarnessAgent — a single API for running established agent harnesses like Claude Code, Codex, and Pi. You don't build the coding-agent loop; you drive one that already exists.
LangGraph is the other bet, and it hasn't moved from it. It reached its first stable 1.0 in October 2025 and it means "low-level." You model your app as a graph: nodes do work, edges decide what runs next, a shared state object threads through. You get durable execution, human-in-the-loop interrupts, and memory — but you write the loop. It is model-agnostic by design and runs in production at Uber, LinkedIn, and Klarna.
The one distinction that decides it#
Strip away the feature lists and the choice is this: inherit a runtime or own the graph.
AI SDK 7 hands you the loop, the streaming UI, the retry semantics, and — with HarnessAgent — an entire coding agent, pre-assembled. The price is a set of assumptions you inherit, several of them shaped like Vercel's own deploy and Workflow infrastructure. That coupling is a feature when you're already there and a tax when you're not.
LangGraph hands you almost nothing pre-decided, on purpose. There is no built-in agent loop because you write it as a graph you can point to in a design review and defend edge by edge. The price is that you own all of it, including the parts AI SDK 7 would have handled while you slept.
AI SDK 7 is leverage you didn't build and can't fully audit. LangGraph is control you pay for in code, every node. Pick the debt you'd rather carry.
Use AI SDK 7 when#
- Your team is TypeScript end to end and you deploy on serverless or edge infra. This is its native habitat; nothing else here fits as cleanly.
- You're building a product — model calls, tools, a streaming UI, and moderate agent structure — not a bespoke multi-agent research system.
- You want durability without building it: WorkflowAgent is the shortest path to "the run survives a deploy."
- You specifically want to orchestrate a coding agent (Claude Code, Codex, Pi) from your own app. HarnessAgent has no LangGraph equivalent, and it's the reason to reach for AI SDK 7 even if you'd otherwise lean graph.
Use LangGraph when#
- You need explicit control flow: deterministic steps interleaved with agentic ones, cyclic graphs, branching you can diagram.
- You're multi-model or refuse to be single-vendor. Routing cheap calls to a small model and hard ones to a frontier model is a graph edge, not a fight with a runtime's assumptions.
- Long-running orchestration and human-in-the-loop are requirements, not nice-to-haves — jobs that survive a crash and pause for an approval before money moves.
- The agent's behavior is the product and you need to inspect, replay, and modify state at every step.
The honest note#
You can run both — LangGraph as the durable, model-agnostic orchestrator, an AI SDK call inside a node when one step is genuinely "stream this to the user." But for a TypeScript team the real tell is your deploy target and your appetite for owning the loop. If you're on TS and shipping a product, AI SDK 7 gets you there this week. If the control flow is the hard part and you'll defend it in review, you want the graph — the same harness-versus-graph fault line runs through Agno vs LangGraph vs CrewAI and every other framework fight worth having. Name the layer you're working at, then pick the tool. That order is the whole trick.
