Using a dedicated Claude Code account for a folder

I wanted one folder tree to use a different Claude Code account without changing the account I use everywhere else. I also wanted the account’s settings and history to remain isolated, without needing a wrapper script or a separate shell alias. I asked an agent to set this up, and the solution turned out to be a single environment variable.

Claude Code supports this through CLAUDE_CONFIG_DIR. When it is set, Claude Code stores its credentials, settings, session history, plugins, MCP state, and per-project memory in that directory instead of ~/.claude. mise can set the variable whenever a shell enters a particular folder tree and remove it again when the shell leaves.

Configuration

At the root of the folder tree, create a mise.toml:

[env]
# Keep this folder tree's Claude Code account and config separate from ~/.claude.
CLAUDE_CONFIG_DIR = "{{ config_root }}/.claude-config"

{{ config_root }} is a mise template that resolves to the directory containing mise.toml. This keeps the setup working if the folder is moved and places all of the isolated Claude Code state inside it.

The mise shell integration needs to be activated. For zsh, I have this in ~/.zshrc:

if command -v mise >/dev/null; then
  eval "$(mise activate zsh)"
fi

Then trust the folder’s configuration:

cd path/to/folder
mise trust

The first time claude runs from that folder, the config directory is empty, so Claude Code starts its login flow. Logging in with the other account saves its credentials under the new config directory rather than changing the default account in ~/.claude. On macOS, its Keychain entry is also namespaced using the config directory path, so it does not collide with the default account.

If the folder is a Git repository, .claude-config/ needs to be ignored because it contains credentials and full session transcripts:

.claude-config/

Verification

Inside the configured folder or any of its subfolders:

$ echo $CLAUDE_CONFIG_DIR
/path/to/folder/.claude-config

Outside that tree, the variable should be empty and claude will use the default ~/.claude configuration again:

cd ~
echo $CLAUDE_CONFIG_DIR

Caveats

This isolates the account and Claude Code state, but it does not install or pin a different version of Claude Code. That would require a [tools] entry in mise.toml.

It also only works in shells where mise is activated. An editor, GUI app, or terminal that does not load the shell configuration will not see CLAUDE_CONFIG_DIR and will use the default account. Settings, permissions, hooks, and plugins from ~/.claude are not inherited, so they need to be configured again or deliberately copied into .claude-config/settings.json.

If the config directory is moved, Claude Code may ask for another login because the macOS Keychain entry is tied to the old path.

This writeup was produced by an agent.