Environment Variables

Authentication

The first variable that is set wins, in the order listed.

Variable	Provider
`SOKET_API_KEY`	Soket
`TENSORSTUDIO_API_KEY`	Soket (alias)
`LOOP_API_KEY`	Soket (alias)
`OPENROUTER_API_KEY`	OpenRouter
`OPENAI_API_KEY`	OpenAI

A hand-written provider in models.json uses whatever names you put in apiKeyEnv. Keys saved with /login live in auth.json and are used when the environment variable is unset. Headless mode (--print, --serve-mcp) cannot open /login. Set a key in the environment, or connect a provider once from the TUI.

Paths

Variable	Default	Description
`LOOP_CODING_AGENT_DIR`	`~/.loop/agent`	Config root
`LOOP_CODING_AGENT_SESSION_DIR`	`~/.loop/agent`	Sessions database location

Installer

Read by https://loop.soket.ai/install and ./install.sh, not by a running loop process.

Variable	Default	Description
`LOOP_INSTALL_DIR`	`~/.loop/bin`	Where the `loop` binary is installed
`LOOP_VERSION`	latest	Same as `--version` (`0.3.4` or `v0.3.4`)
`LOOP_ALLOW_UNVERIFIED`	unset	`1` installs when the release has no published checksum. Otherwise the installer stops
`GITHUB_TOKEN`	unset	GitHub API token, to avoid rate limits while resolving the release

Editor

Variable	Description
`EDITOR`	External editor for `Ctrl+G` (for example `vim` or `code --wait`)

Logging

Variable	Description
`LOOP_DEBUG`	`1`, `true`, or `yes` — same as `--debug`. Writes logs under `cwd/target/debug/logs`. The TUI logs to that file only, so stderr does not corrupt the screen
`RUST_LOG`	`tracing` filter. When unset, the level is `warn`, or a debug filter for Loop crates if debug mode is on

export RUST_LOG=loop_agent=debug,loop_ai=info,warn

Tracing

Read when Loop is built with --features telemetry. If all three Langfuse variables are set, they override /tracing setup.

Variable	Description
`LANGFUSE_HOST`	Langfuse base URL
`LANGFUSE_PUBLIC_KEY`	Langfuse public key
`LANGFUSE_SECRET_KEY`	Langfuse secret key
`TRACEPARENT`	W3C traceparent for `--print` (same as `--trace-parent`)

See Tracing.

Examples

export SOKET_API_KEY="your-key"
export LOOP_CODING_AGENT_DIR="$HOME/.config/loop"
export EDITOR="code --wait"
loop

export OPENROUTER_API_KEY="$CI_OPENROUTER_KEY"
loop --model openrouter/openai/gpt-4o --print "review this diff for bugs"

​Authentication

​Paths

​Installer

​Editor

​Logging

​Tracing

​Examples