Vercel AI SDK
the dominant ts llm sdk, with agent helpers on top
the de facto typescript llm sdk with a genuine agent loop layer and huge real-world usage — but thinner as an orchestration framework than mastra, which is why it sits just below it on this axis.
the vercel ai sdk is the provider-abstraction and streaming/ui layer that a large share of typescript llm apps are built on, with an agent loop on top (generatetext/streamtext with tools and stopwhen, plus an agent abstraction). its model abstraction and streaming dx are excellent and its adoption is enormous. cross-provider is the whole point.
but as a full agent-orchestration framework it's thinner than mastra — multi-agent is lighter, and it's not a durable-execution engine — so for heavy orchestration you pair it with a workflow engine. ranked on the agent-framework axis specifically, that's why it's below mastra despite far larger overall usage. (licence note: github mislabels it, but the file is apache-2.0.)
the description above is ours, condensed from the ranking. pricing moves — check it on the vendor's own page before you rely on it.
- category
- ai agent frameworks
- pricing
- free — Apache-2.0 (open source)
- website
- github.com
the de facto typescript llm sdk with a genuine agent loop layer and huge real-world usage — but thinner as an orchestration framework than mastra, which is why it sits just below it on this axis.
we researched this category against vendors' own pricing pages and licence files. that is where this line comes from — not from the vendor, and not from anything they paid for.