Environment variables

All variables are read once at startup; restart the server to apply a change.

Core

Variable	Default	What it does
CPTR_DATA_DIR	~/.cptr	Data directory for the database, config, uploads, and logs. The Docker image sets it to /data.
CPTR_LOG_LEVEL	INFO	Server log level.
CPTR_LOG_FORMAT	text	text or json (structured output for log collectors).
CPTR_AUDIT_LOG_LEVEL	NONE	NONE disables audit logging; METADATA records mutations; REQUEST adds redacted request bodies; REQUEST_RESPONSE adds redacted response bodies.
CPTR_AUDIT_LOG_PATH	<data>/logs/audit.jsonl	Audit log file location.
CPTR_AUDIT_LOG_ROTATION	10 MB	Audit log rotation size.
CPTR_AUDIT_MAX_BODY_SIZE	2048	Max bytes of request/response body captured per audit entry.
CPTR_AUDIT_EXCLUDED_PATHS	/api/chats,/v1/chat	Paths excluded from audit logging.
CPTR_LOG_UPSTREAM_REQUESTS	false	Log outgoing model API requests, for debugging model calls.
CPTR_UPSTREAM_REQUEST_LOG_PATH	<data>/logs/upstream-requests.jsonl	Upstream request log location.
CPTR_UPSTREAM_REQUEST_LOG_ROTATION	50 MB	Upstream request log rotation size.

Chat and agent tuning

Variable	Default	What it does
CHAT_MAX_ITERATIONS	2048	Max tool-call iterations per turn before the agent is stopped.
ENABLE_CHAT_RECONCILE_ON_STARTUP	true	On startup, recover chats left stuck by a crash.
CHAT_TOOL_MAX_CHARS	50000	Max characters of a tool's output kept in context.
CHAT_TOOL_COMMAND_MAX_CHARS	8000	Max characters of command output kept in context.
CHAT_COMPACT_TOKEN_THRESHOLD	80000	Token count that triggers context compaction.
CPTR_CLAUDE_CODE_MAX_BUFFER_SIZE	134217728	Stdout buffer size (bytes) for the Claude SDK subprocess.
CPTR_EXECUTE_TIMEOUT	unset	Default wait in seconds for run_command before it returns while the command keeps running.
CPTR_STREAM_CONNECT_TIMEOUT	30	Seconds to wait when connecting to a model stream.
CPTR_STREAM_READ_TIMEOUT	300	Seconds to wait for the next chunk from a model stream.
CPTR_STREAM_WRITE_TIMEOUT	600	Seconds to wait when writing to a model stream.

Scheduler

Variable	Default	What it does
AUTOMATION_POLL_INTERVAL	10	How often (seconds) the scheduler checks for due automations.

Network

Variable	Default	What it does
CPTR_CORS_ALLOWED_ORIGINS	*	Comma-separated list of browser origins allowed to call the API.

Web search providers

Keys set here take precedence over keys entered in Settings. With no key at all, web search falls back to DuckDuckGo; otherwise the first configured provider in this order wins: Exa → Perplexity → Tavily → Brave → Firecrawl → SearXNG → DuckDuckGo.

Variable	Default	What it does
EXA_API_KEY	unset	Exa search.
PERPLEXITY_API_KEY	unset	Perplexity search.
PERPLEXITY_BASE_URL	unset	Custom Perplexity endpoint.
TAVILY_API_KEY	unset	Tavily search.
BRAVE_API_KEY	unset	Brave search.
FIRECRAWL_API_KEY	unset	Firecrawl search.
FIRECRAWL_BASE_URL	unset	Custom Firecrawl endpoint.
SEARXNG_BASE_URL	unset	Self-hosted SearXNG instance.
CHAT_COMPLETIONS_SEARCH_API_KEY	unset	Search via an OpenAI-compatible chat-completions endpoint.
CHAT_COMPLETIONS_SEARCH_BASE_URL	unset	Base URL for that endpoint.
CHAT_COMPLETIONS_SEARCH_MODEL	unset	Model for that endpoint.
XAI_API_KEY	unset	Used for Grok agent detection.