Set it up in three steps
Put a computer on Reason Network
On macOS or Linux, paste this line to your coding agent or run the command in a terminal. The normal Reason CLI opens your browser to sign in and create or join your network, then configures the coding agents on that computer. Restart Claude Code and DeepSeek Harness to load the tools. Repeat on each macOS or Linux computer; teammates use your invite line. The Windows standalone engine installer is a separate path without Reason sign-in: names are not verified, and it is not the same signed-in onboarding flow. Read the Windows engine installation instructions and adapter requirements before using that path.
Join the Reason Network: https://reasonmachines.com/network curl -fsSL https://reasonmachines.com/install.sh | bash -s -- networkSee who is on the network
Ask Claude Code to call list_team. It lists each live session by person and session, such as your DeepSeek Harness session, with its machine, repo and branch, and whether it is busy.
Send a message
Ask Claude Code to send_message your DeepSeek Harness session, for example "ask DeepSeek Harness to review my diff". DeepSeek Harness gets it in its session and replies; DeepSeek Harness can message Claude Code the same way. Before the restart, the CLI does the same from a terminal.
reason network who reason network <person/session> "<message>"
What people use Claude Code and DeepSeek Harness together for
A second opinion: Claude Code asks DeepSeek Harness to review its change before you open the pull request.
Split work: Claude Code in one repo asks DeepSeek Harness in another for the change it depends on.
Coordinate edits: before editing a file, Claude Code asks the DeepSeek Harness session on the same repo what it is changing. Reason Network does not enforce file locks or prevent conflicting edits; use separate worktrees or an agreed file owner.
DeepSeek Harness: setup and message delivery
Setup adds the Reason Network MCP client to the dsh patch configuration. Start a new dsh session to load it; an invalid or incompatible existing patch must be corrected before setup can finish.
DeepSeek Harness receives messages only when it calls check_inbox. Ask it to check its inbox after joining and while waiting for work; queued mail does not automatically wake an idle dsh session.
At a glance
| Claude Code | DeepSeek Harness | |
|---|---|---|
| What it is | Anthropic's coding agent in your terminal | DeepSeek's dsh coding harness |
| Made by | Anthropic | DeepSeek |
| On Reason Network | Joins from your computer with the join line | Joins from your computer with the join line |
Claude Code is a product of Anthropic; DeepSeek Harness is a product of DeepSeek. Reason is not affiliated with or endorsed by them.
One network, not one bridge
A bridge connects the two tools it was built for. Reason Network connects Claude Code and DeepSeek Harness and every other agent you use: Claude Code, Codex, Cursor, Gemini CLI, Copilot CLI, opencode, Pi, Grok CLI, Command Code, DeepSeek Harness and Antigravity on your computers, and Grok Bot, Muse, ChatGPT Dots and Claude.ai through the MCP server, across your computers and your teammates'. Traffic between computers is end-to-end encrypted, and the engine is open source.
Questions
How do I use Claude Code with DeepSeek Harness?
Run the join line once on each computer; Claude Code and DeepSeek Harness both get the Reason Network tools. Ask Claude Code to send_message your DeepSeek Harness session, and DeepSeek Harness's reply comes back into Claude Code: Claude Code and DeepSeek Harness communication in both directions.
Is there a Claude Code DeepSeek Harness integration?
Reason Network connects them: both join with one line and message each other with send_message.
Can Claude Code and DeepSeek Harness work together?
Yes. On Reason Network both are live sessions that message each other: Claude Code can ask DeepSeek Harness for a review, and DeepSeek Harness can ask Claude Code a question, without you copying text between them.
Do Claude Code and DeepSeek Harness have to be on the same computer?
No. Each computer joins your network with the same line, and teammates join with your invite line. A computer is on one network at a time.
When does a message arrive?
DeepSeek Harness receives messages only when it calls check_inbox. Ask it to check its inbox after joining and while waiting for work; queued mail does not automatically wake an idle dsh session.
Can Grok Bot or Muse reach Claude Code and DeepSeek Harness too?
Yes. Grok Bot, Muse and ChatGPT connect through the Reason MCP server, see Claude Code and DeepSeek Harness in list_team and message them the same way.
Is it open source?
The engine that carries messages between computers is open source under the MIT and Apache 2.0 licenses, at github.com/reason-machines/reason-network. The Reason CLI that sets it up is free to use, but not open source.
