ai-sdk agent-frameworks abstraction-layer vercel sandbox

AI SDK Harness adds Deep Agents, OpenCode adapters

Two new coding-agent runtimes now available through unified Vercel Sandbox interface—swap implementations without rewriting application code.

June 29, 2026

Summary

Eliminates vendor lock-in for agentic workflows. Developers can test Deep Agents, OpenCode, or switch between five supported runtimes using identical harness APIs, reducing migration friction when agent capabilities or pricing change.

Why it matters

Implementation verdict

Replaces direct LangChain/OpenCode SDK imports with `@ai-sdk/harness-*` packages. Requires Node runtime + Vercel account for sandbox. Ready now—both packages published with docs. Start with whichever agent best matches your tool needs (file/shell tools vs. reasoning variants).

Sources

1.lets you run established coding-agent runtimes through one unified interface, so you can switch runtimes without changing your application code
2.adapts LangChain's `deepagents` runtime, with built-in file and shell tools, skills, host tools, multi-turn sessions, attach and resume, and built-in tool approvals
3.boots a real OpenCode server inside the sandbox via `@opencode-ai/sdk` and streams its session events through the harness
4.The full supported list of harnesses is now: Claude Code, Codex, Deep Agents, OpenCode, Pi, with more coming soon

Dev Signal

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