hythe — Claude Code MCP server for agent coordination
hythe lets coding agents share state, exchange messages, and carry context between sessions. Use it when multiple agents need to coordinate on the same work.
claude mcp add --env HYTHE_AGENT_ID=<HYTHE_AGENT_ID> --env HYTHE_AGENT_KEY_FILE=<HYTHE_AGENT_KEY_FILE> --env HYTHE_AGENT_AUTH_MODE=<HYTHE_AGENT_AUTH_MODE> --env API_KEY=<API_KEY> --env MCP_HOST=<MCP_HOST> --transport stdio hythe -- npx -y @hythe/mcpWhat hythe does
hythe runs as a self-hosted MCP server with a lightweight stdio bridge for clients. Agents can share project state, send messages, and continue with context from earlier sessions. When observations replace earlier ones, the server resolves the chain and returns the current surviving state.
Concurrent checkpoint changes create separate branches; conflicts remain visible instead of being silently settled. Messages have tracked states for delivery, reading, and archiving, but that lifecycle does not promise delivery. The Claude Code install command requires HYTHE_AGENT_ID and API_KEY, then starts @hythe/mcp with npx.
What it helps with
- share project state across coding agents
- carry context from one session into another
- find the current version after observations replace earlier ones
- surface conflicts from concurrent checkpoint updates
Example prompts for the agent
- Save the current project state so another agent can pick up the work.
- Send a message to the agent reviewing these changes.
- Check which state version is current for this scope.
How to install hythe
Platform CLI
claude mcp add --env HYTHE_AGENT_ID=<HYTHE_AGENT_ID> --env HYTHE_AGENT_KEY_FILE=<HYTHE_AGENT_KEY_FILE> --env HYTHE_AGENT_AUTH_MODE=<HYTHE_AGENT_AUTH_MODE> --env API_KEY=<API_KEY> --env MCP_HOST=<MCP_HOST> --transport stdio hythe -- npx -y @hythe/mcpReplace <…> with your own values. 1 more environment variable is in the server README
Platform CLI
codex mcp add hythe --env HYTHE_AGENT_ID=<HYTHE_AGENT_ID> --env HYTHE_AGENT_KEY_FILE=<HYTHE_AGENT_KEY_FILE> --env HYTHE_AGENT_AUTH_MODE=<HYTHE_AGENT_AUTH_MODE> --env API_KEY=<API_KEY> --env MCP_HOST=<MCP_HOST> -- npx -y @hythe/mcpReplace <…> with your own values. 1 more environment variable is in the server README
Config file
{
"mcpServers": {
"hythe": {
"command": "npx",
"args": [
"-y",
"@hythe/mcp"
],
"env": {
"HYTHE_AGENT_ID": "<HYTHE_AGENT_ID>",
"HYTHE_AGENT_KEY_FILE": "<HYTHE_AGENT_KEY_FILE>",
"HYTHE_AGENT_AUTH_MODE": "<HYTHE_AGENT_AUTH_MODE>",
"API_KEY": "<API_KEY>",
"MCP_HOST": "<MCP_HOST>"
}
}
}
}Replace <…> with your own values. 1 more environment variable is in the server README
Config file
{
"servers": {
"hythe": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@hythe/mcp"
],
"env": {
"HYTHE_AGENT_ID": "<HYTHE_AGENT_ID>",
"HYTHE_AGENT_KEY_FILE": "<HYTHE_AGENT_KEY_FILE>",
"HYTHE_AGENT_AUTH_MODE": "<HYTHE_AGENT_AUTH_MODE>",
"API_KEY": "<API_KEY>",
"MCP_HOST": "<MCP_HOST>"
}
}
}
}Replace <…> with your own values. 1 more environment variable is in the server README
Platform CLI
gemini mcp add -e HYTHE_AGENT_ID=<HYTHE_AGENT_ID> -e HYTHE_AGENT_KEY_FILE=<HYTHE_AGENT_KEY_FILE> -e HYTHE_AGENT_AUTH_MODE=<HYTHE_AGENT_AUTH_MODE> -e API_KEY=<API_KEY> -e MCP_HOST=<MCP_HOST> hythe npx -y @hythe/mcpReplace <…> with your own values. 1 more environment variable is in the server README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about hythe
How do I install hythe in Claude Code?
Run claude mcp add hythe -e HYTHE_AGENT_ID=<HYTHE_AGENT_ID> -e API_KEY=<API_KEY> -- npx -y @hythe/mcp. Set the agent ID and API key values.
What does hythe do?
It gives multiple coding agents shared state, messaging, and context that carries across sessions. Concurrent updates can remain visible as conflicts.
What does Claude Code need to connect to hythe?
This install method uses HYTHE_AGENT_ID and API_KEY. Claude Code starts the @hythe/mcp package through npx.
