AFK is configured primarily through code. Environment variables provide fallback defaults for LLM settings, memory backends, queues, and prompt directories. Runtime configuration APIs always take precedence.
All variables are optional. If unset, AFK uses the defaults listed below.
LLM defaults
These variables configure the default LLM provider and behavior. They are read by LLMSettings.from_env() at startup.
| Variable | Default | Description |
|---|
AFK_LLM_PROVIDER | litellm | Default provider id (openai, litellm, anthropic_agent) |
AFK_LLM_MODEL | gpt-5.2-mini | Default model name |
AFK_EMBED_MODEL | (none) | Embedding model for vector operations |
AFK_LLM_API_BASE_URL | (none) | Provider API base URL |
AFK_LLM_API_KEY | (none) | Provider API key |
AFK_LLM_TIMEOUT_S | 30 | Request timeout in seconds |
AFK_LLM_STREAM_IDLE_TIMEOUT_S | 45 | Stream idle timeout in seconds |
AFK_LLM_MAX_RETRIES | 3 | Retry attempts on transient failures |
AFK_LLM_BACKOFF_BASE_S | 0.5 | Exponential backoff base in seconds |
AFK_LLM_BACKOFF_JITTER_S | 0.15 | Random jitter added to backoff |
AFK_LLM_JSON_MAX_RETRIES | 2 | Structured output repair attempts |
AFK_LLM_MAX_INPUT_CHARS | 200000 | Input truncation ceiling in characters |
API keys for specific providers (e.g. OPENAI_API_KEY,
ANTHROPIC_API_KEY) are read by the underlying provider libraries, not by AFK
directly. Set AFK_LLM_API_KEY only if you want a single key shared across
providers.
Memory
Configure the persistent memory backend for thread-based conversations.
| Variable | Default | Description |
|---|
AFK_MEMORY_BACKEND | sqlite | Backend type: inmemory, sqlite, redis, postgres |
AFK_SQLITE_PATH | afk_memory.sqlite3 | SQLite file path |
AFK_REDIS_URL | (none) | Redis connection URL (e.g. redis://localhost:6379) |
AFK_PG_DSN | (none) | PostgreSQL connection string |
# Override in code — takes precedence over env vars
from afk.core import Runner
runner = Runner(memory_store=my_custom_store)
Queue
Configure the task queue backend for async agent execution.
| Variable | Default | Description |
|---|
AFK_QUEUE_BACKEND | inmemory | Backend type: inmemory, redis |
AFK_QUEUE_RETRY_BACKOFF_BASE_S | 0.5 | Retry base delay in seconds |
AFK_QUEUE_RETRY_BACKOFF_MAX_S | 30 | Retry max delay in seconds |
AFK_QUEUE_RETRY_BACKOFF_JITTER_S | 0.2 | Random jitter added to backoff |
The inmemory queue backend does not persist across restarts. Use redis for
production workloads that need reliable task delivery.
Prompts
| Variable | Default | Description |
|---|
AFK_AGENT_PROMPTS_DIR | .agents/prompt | Root directory for system prompt files |
instruction_file paths relative to this directory. See System Prompts for details.
A2A
No default environment variables are required. Configure A2A host and authentication in code for an explicit security posture. See A2A for details.
Precedence
Configuration is resolved in this order (highest priority first):
- Constructor arguments —
Runner(memory_store=...), Agent(model=...)
RunnerConfig / LLMSettings objects — passed to constructors- Environment variables — fallback defaults listed on this page
- Built-in defaults — hardcoded in the source
Next steps
