Start on Claude Code. Continue on Codex.
Open source, realtime and invisible context infrastructure for the ones shipping at inference speed.

Documentation · API Reference · Changelog

What Claude Code knows, Codex doesn't. What your teammate is shipping right now? Your agent has no idea.

UltraContext captures every agent's context in realtime and makes it available to all of them. It's like having a personal context engineer everywhere. Continue a session in a different agent, or just ask what's happeming.

For example:

• "Codex, grab the last plan Claude Code made and implement it."
• "What's the team building today?"
• "What is Alex working on in Codex right now?"

Open source. Framework-agnostic. Customizable via the git-like Context API.

1. Start sync. It captures all your agents' context in realtime.

2. Add the MCP server. Any agent gets full awareness of every other agent.

3. That's it. Ask questions, continue sessions, fork — your context is everywhere.

Requires Node >= 22.

npm install -g ultracontext

ultracontext          # start sync (daemon + dashboard)

That's it. UltraContext watches your agents, ingests context in realtime, and the dashboard shows everything.

ultracontext sync     # start sync (daemon + dashboard)
ultracontext stop     # stop daemon
ultracontext config   # run setup wizard
ultracontext update   # update CLI globally

For builders who want to go deeper. Git-like primitives for context engineering.

• Five methods — Create, get, append, update, delete. That's it.
• Automatic versioning — Every change creates a new version. Full history out of the box.
• Time-travel — Jump to any point in your context history.
• Framework-agnostic — Works with any LLM framework. No vendor lock-in.

Use the API standalone to build your own agents, or extend existing ones in UltraContext.

npm install ultracontext

import { UltraContext } from 'ultracontext';

const uc = new UltraContext({ apiKey: 'uc_live_...' });

const ctx = await uc.create();
await uc.append(ctx.id, { role: 'user', content: 'Hello!' });

// use with any LLM framework
const response = await generateText({ model, messages: ctx.data });

pip install ultracontext

from ultracontext import UltraContext

uc = UltraContext(api_key="uc_live_...")

ctx = uc.create()
uc.append(ctx["id"], {"role": "user", "content": "Hello!"})

# use with any LLM framework
response = generate_text(model=model, messages=uc.get(ctx["id"])["data"])

📚 Context API Guides

Store & Retrieve · Edit Contexts · Fork & Clone · View History

• Quickstart — Get running in 2 minutes
• Guides — Practical patterns for common use cases
• API Reference — Full endpoint documentation