argon — Claude Code MCP server: branch and undo MongoDB
Gives an AI agent a versioned MongoDB sandbox: branch off, review, merge or roll back. Useful when the agent writes to a database.
claude mcp add argon -- npx -y argonctlWhat argon does
argon layers version history on top of MongoDB. A branch is a metadata write, so it appears at once and copies nothing; argon checkout then materializes it as a real database that pymongo, mongoose, mongosh, indexes, aggregations and transactions all work against. Document writes that capture supports land in history.
From there you inspect changes with argon diff, merge them back as a reviewable plan, or revert by actor label and range. Sandboxes carry a TTL, dataset pins hold a captured state, and argon console serves a local UI plus REST API. Agents reach the same operations through 13 MCP tools, and a Python SDK ships with a LangGraph adapter.
Stop source writers before an import, or the data will drift. MongoDB has to run as a replica set; a single node is enough. History covers inserts, updates, replacements and deletes — dropping or renaming a collection degrades capture, and indexes and collection options are not versioned. Building from source needs Go 1.26.9 or newer; the npm route wants Node.js 24 LTS and npm 11.16 or newer.
What it helps with
- undo the database changes an agent made during a session
- review data edits before they reach the main branch
- hand an agent a disposable sandbox that expires on its own
- freeze a dataset state for repeatable eval runs
- read a document's history at a chosen point in time
Example prompts for the agent
- Create a branch called
experimentin projectmyappand print the connection string - Diff branch
experimentagainstmainand prepare a merge plan - Revert the changes from actor
agent:experimentin projectmyapp
How to install argon
Platform CLI
claude mcp add argon -- npx -y argonctlPlatform CLI
codex mcp add argon -- npx -y argonctlConfig file
{
"mcpServers": {
"argon": {
"command": "npx",
"args": [
"-y",
"argonctl"
]
}
}
}Config file
{
"servers": {
"argon": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"argonctl"
]
}
}
}Platform CLI
gemini mcp add argon npx -y argonctlStep 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 argon
How do I install argon in Claude Code?
Run claude mcp add argon -- npx -y argonctl. The server then shows up in your Claude MCP server list.
What does argon do?
It versions MongoDB data: branches, captured document changes, diffs, merges and rollbacks. An agent drives those operations over MCP.
What does argon need to run?
MongoDB as a replica set — one node is fine. Before importing a database, stop the writers on the source.
