Mastra vs AI SDK

Two sides of the AI SDK & agent framework decision: typeScript framework and thin SDK. When each fits, what it costs, who moves from one to the other, and what makers who chose it say.

Ask your AI about this, with this page as the source:ChatGPT ↗Claude ↗Perplexity ↗

Which fits you

Choose Mastra if
  • Your app is TypeScript and you want agents without adding a Python service

Use it whenYou want a full agent framework — workflows, memory, evals — in the same TypeScript codebase as your app.

Trade-offYounger ecosystem, and some enterprise features sit under a separate source-available license.

Choose AI SDK if
  • Your app is TypeScript and you want agents without adding a Python service

Use it whenYou already use the AI SDK for chat and want the agent in the same code.

Trade-offMemory, workflows and evals are left to you or other libraries.

At a glance

MastraAI SDK
Used by24 makers' products · 13 open-source projects4 makers' products · 193 open-source projects
Downloads1.4M/wk3.6× vs npm21.2M/wk+167% vs npm
PricingCore framework free and open source; enterprise features under a separate source-available license. · paid from $250/moFree (open source).
Free tierYesYes
Open sourceYes · self-hostableYes · self-hostable

What makers say

Makers on using it for AI SDK & agent framework, from Product Hunt and Starter Story interviews, each linked to the source. Products with a page of their own and fuller notes first.

On Mastra
Really like the depth of product here, very hard to make a product of this scale high quality, impressed!
siift, the makerSep 2026 ↗
Mastra powers our chat infrastructure and makes developing a coding agent seamless
superset, the makerSep 2026 ↗
Shoutout to the team at Mastra for building an excellent agent orchestration layer. Mastra is a key part of Imagine.dev’s agentic architecture, helping us coordinate specialized agents and reliably turn high-level intent into structured execution. Their focus on developer experience and composability made it possible…
Imagine, the makerSep 2026 ↗
2 more on the Mastra page →
On AI SDK
Used for multi-agent orchestration, state management, debugging, and structured artifact streaming for our AI application.
Quartr, the makerSep 2026 ↗
AI SDK made super simple to integrate all the different models into our app. Its the best sdk for build ai apps right now.
Sparks AI, the makerSep 2026 ↗
• TypeScript-first, ergonomic API with excellent Next.js integration; streaming and tool calling are rock solid. • Consistent abstractions across multiple model providers (great with OpenRouter) minimize vendor lock-in and churn. • Clear docs and examples reduce boilerplate and accelerate iteration; fewer edge-case f…
onlook, the makerSep 2026 ↗
2 more on the AI SDK page →

Loved and watch-outs

Themes that recur in makers' words and Hacker News comments, each linked to what it summarises.

Mastra
Most loved
Watch-outs
  • Workflows with rule-based, non-LLM branching feel clunky, pushing some to write their own. HN
  • The Elastic v2 license bars offering it as a hosted service, so it is not open source in the usual sense. HN
  • Several Mastra npm packages were compromised in a supply-chain attack. HN
On Product Hunt: 5.0★, 9 reviews
AI SDK
Most loved
  • One TypeScript API across many model providers, so swapping models needs no code rewrite. PHPH 2HN
  • Streaming and tool calling are dependable, with tight Next.js and React integration. PHHNPH 2
  • A well-written core that other agent libraries build on, with version-matched docs shipped in the package. HNHN 2HN 3HN 4
Watch-outs
  • Easy to drop in but hard to make resilient: no resumable streaming after a dropped connection and no multi-device support. HNHN 2
  • Streaming tool-call JSON is re-parsed on every chunk, which stalls on large payloads. HN
On Product Hunt: 5.0★, 5 reviews

Who uses each

Used by both — often one replacing the other, or each for a different part of the product

What makers pair each with

With AI SDK
LangChainBroad frameworkThe largest set of ready-made integrations for models, tools and data sources, in Python and JavaScript.vs Mastra →
LlamaIndexBroad frameworkAgents that mostly retrieve and reason over your own documents.
OpenAI Agents SDKThin SDKA small agent loop with tools, handoffs, guardrails and tracing built in, from the OpenAI team.
Pydantic AIThin SDKPython agents whose outputs must validate against typed schemas, across any model provider.
Claude Agent SDKAgent harnessAgents that read and edit files, run shell commands and manage long context, built on the same harness as Claude Code.
LangGraphMulti-agent orchestrationStateful agents built as an explicit graph of steps, with checkpoints, retries, streaming and pauses for human approval, in Python or JavaScript.