Configuration

Config section: ai_session
Env prefix: LEX_AI_SESSION__

ai_session:
  backend: database
  session_ttl: 86400
  auto_checkpoint_interval: 10
  max_turns_per_session: 1000

Reference table

Key	Type	Default	Env var	Description
`enabled`	`bool`	`True`	`LEX_AI_SESSION__ENABLED`	Enable the AI session subsystem
`name`	`str`	`"ai-session"`	`LEX_AI_SESSION__NAME`	Logical DI registration key
`default_system_prompt`	`str \| None`	`None`	`LEX_AI_SESSION__DEFAULT_SYSTEM_PROMPT`	System prompt injected into every new session
`session_ttl`	`int`	`86400`	`LEX_AI_SESSION__SESSION_TTL`	Max session age in seconds (0 to disable)
`cleanup_interval_s`	`int`	`600`	`LEX_AI_SESSION__CLEANUP_INTERVAL_S`	Cleanup sweep interval in seconds
`max_turns_per_session`	`int`	`1000`	`LEX_AI_SESSION__MAX_TURNS_PER_SESSION`	Hard cap on turns before session closes
`max_sessions_per_user`	`int`	`100`	`LEX_AI_SESSION__MAX_SESSIONS_PER_USER`	Maximum concurrent sessions per user
`auto_checkpoint_interval`	`int \| None`	`10`	`LEX_AI_SESSION__AUTO_CHECKPOINT_INTERVAL`	Checkpoint every N turns; `None` to disable
`max_checkpoints_per_session`	`int`	`50`	`LEX_AI_SESSION__MAX_CHECKPOINTS_PER_SESSION`	Maximum retained checkpoints per session
`max_branches_per_session`	`int`	`10`	`LEX_AI_SESSION__MAX_BRANCHES_PER_SESSION`	Maximum forked branches per session
`max_agents_per_group`	`int`	`10`	`LEX_AI_SESSION__MAX_AGENTS_PER_GROUP`	Maximum agents in a multi-agent group session
`default_turn_strategy`	`str`	`"round_robin"`	`LEX_AI_SESSION__DEFAULT_TURN_STRATEGY`	Default turn strategy (`round_robin`, `priority`, `llm_directed`)
`backend`	`str`	`"in_memory"`	`LEX_AI_SESSION__BACKEND`	Persistence backend (`in_memory`, `cache`, `database`)
`cookie_name`	`str \| None`	`"lexigram_session"`	`LEX_AI_SESSION__COOKIE_NAME`	Cookie name for web session ID; `None` disables cookies
`header_name`	`str`	`"X-Session-ID"`	`LEX_AI_SESSION__HEADER_NAME`	HTTP header name for session ID pass-through
`consolidate_on_close`	`bool`	`True`	`LEX_AI_SESSION__CONSOLIDATE_ON_CLOSE`	Trigger memory consolidation on session close

Env var override example

export LEX_AI_SESSION__BACKEND=database
export LEX_AI_SESSION__SESSION_TTL=43200
export LEX_AI_SESSION__MAX_TURNS_PER_SESSION=500
export LEX_AI_SESSION__AUTO_CHECKPOINT_INTERVAL=5

Production example

ai_session:
  backend: database
  session_ttl: 43200
  cleanup_interval_s: 300
  max_turns_per_session: 500
  max_sessions_per_user: 50
  auto_checkpoint_interval: 5
  max_checkpoints_per_session: 100
  consolidate_on_close: true
  cookie_name: session_id
  header_name: X-Session-ID