AI / LLM Tooling

TypeScript SDKs / orchestration

• ★ Vercel AI SDK — provider-agnostic streaming, tool calling, structured outputs, generative UI. The default for new TS LLM apps in 2026.
• Mastra — TypeScript framework for agents, workflows, RAG, evals. From the Gatsby founders.
• LangChain.js — large, sometimes opinionated; mature retrieval/agent abstractions.
• LlamaIndex.ts — strong RAG / index abstractions.
• @anthropic-ai/sdk, openai, @google/generative-ai — provider-direct SDKs.
• Ollama + ollama-js — local models.

Agent / orchestration frameworks

• Inngest Agents — durable agent workflows on top of Inngest.
• Trigger.dev with AI tools — durable LLM workflows.
• CrewAI, AutoGen — multi-agent orchestration (Python-first; TS bindings emerging).

Vector / embeddings

• pgvector + Postgres — for most apps, this is enough.
• pgvectorscale — Timescale's vector index for huge corpora.
• Pinecone, Qdrant, Weaviate, Milvus, Chroma — dedicated vector DBs.
• Cloudflare Vectorize — Workers-native vector DB.
• Turbopuffer, LanceDB — newer high-performance options.

LLM gateways / observability

• Vercel AI Gateway, Cloudflare AI Gateway, Helicone, LangSmith, Langfuse, Braintrust, Arize Phoenix — pick at least one for production: caching, retries, traces, costs, evals.

Embeddings + chunking helpers

• @upstash/ragify, LangChain text splitters, unstructured, Chonkie — chunking and ingestion.

Tool / agent UIs

• assistant-ui — React components for chat UIs.
• CopilotKit — embed AI copilots into existing apps.
• Vercel AI SDK UI — useChat and friends; the default React chat hooks.

Local / on-device

• Transformers.js — Hugging Face Transformers in the browser via WebGPU.
• WebLLM — run LLMs in the browser via WebGPU.
• MLX — Apple-silicon-native (TS bindings emerging).

Pick this if…

• Default new project: Vercel AI SDK + your provider's API.
• Agentic / multi-step durability: Mastra or Inngest Agents.
• Heavy RAG focus: LlamaIndex.ts + pgvector (or Pinecone/Qdrant).
• Need observability and caching: add an AI Gateway from day one.