Configuration

AI Labs reads all of its tunables from environment variables. Server basics (host, port, auth mode, JWT secret) also live in ~/.cptr/config.toml; everything an admin can change is in the Admin settings and stored in the database.

Data directory

Variable	Default	Purpose
CPTR_DATA_DIR	~/.cptr	Where the database (app.db), config.toml, logs/, memory/, and uploads live. Set to /data in Docker.

Logging

Variable	Default	Purpose
CPTR_LOG_LEVEL	INFO	Application log level.
CPTR_LOG_FORMAT	text	text or json.
CPTR_LOG_UPSTREAM_REQUESTS	false	Capture full upstream model requests.
CPTR_UPSTREAM_REQUEST_LOG_PATH	<data>/logs/upstream-requests.jsonl	Where they go.
CPTR_UPSTREAM_REQUEST_LOG_ROTATION	50 MB	Rotation size.

Audit log

Variable	Default	Purpose
CPTR_AUDIT_LOG_LEVEL	NONE	Set to a level to enable the audit trail.
CPTR_AUDIT_LOG_PATH	<data>/logs/audit.jsonl	Output file.
CPTR_AUDIT_LOG_ROTATION	10 MB	Rotation size.
CPTR_AUDIT_MAX_BODY_SIZE	2048	Max request-body bytes recorded.
CPTR_AUDIT_EXCLUDED_PATHS	/api/chats,/v1/chat	Comma-separated path prefixes to skip.

Chat & agent

Variable	Default	Purpose
CHAT_MAX_ITERATIONS	2048	Max tool-loop iterations per turn.
CHAT_TOOL_MAX_CHARS	50000	Truncation cap for tool output.
CHAT_TOOL_COMMAND_MAX_CHARS	8000	Truncation cap for command output.
CHAT_COMPACT_TOKEN_THRESHOLD	80000	Default context-compaction threshold (overridable per model).
CHAT_AGENT_SEED_TRANSCRIPT_MAX_CHARS	12000	How much recent context seeds a coding-agent session.
CPTR_CLAUDE_CODE_MAX_BUFFER_SIZE	128 MiB	stdout JSON buffer for the Claude Code backend.
ENABLE_CHAT_RECONCILE_ON_STARTUP	true	Reconcile interrupted chats on boot.
CPTR_EXECUTE_TIMEOUT	unset (return immediately)	Default wait (seconds) for run_command / check_task when no explicit wait is given.

Streaming timeouts

Variable	Default
CPTR_STREAM_CONNECT_TIMEOUT	30
CPTR_STREAM_READ_TIMEOUT	300
CPTR_STREAM_WRITE_TIMEOUT	600

Workspace

Variable	Default	Purpose
CPTR_AUTO_GITIGNORE_DOT_CPTR	true	Auto-add .cptr/ to a workspace's .gitignore.

Schedulers

Variable	Default	Purpose
AUTOMATION_POLL_INTERVAL	10	Seconds between automation scheduler checks.
TIMER_POLL_INTERVAL	1	Seconds between timer-worker checks.

Networking

Variable	Default	Purpose
CPTR_CORS_ALLOWED_ORIGINS	*	Socket.IO CORS origins. Comma-separated list to restrict.
CPTR_PORT	set by CLI	Port advertised to the frontend.

Backups

Variable	Default	Purpose
CPTR_BACKUP	0	Set to 1 to stream the database to a replica via Litestream (litestream.yml), with automatic restore on a fresh volume.

Startup token

Variable	Purpose
CPTR_STARTUP_TOKEN	One-time first-run setup token. Set by cptr run, consumed by the app — you normally don't set this yourself.