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The Cron Scheduler and Routines subsystem provides the background orchestration layer for Palyra. It manages time-based job execution, recurring automation routines, and essential system maintenance tasks like memory vacuuming and skill re-auditing.

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Cron Scheduler Loop

The core of the scheduling system is a background loop within palyrad that monitors pending jobs in the JournalStore. The scheduler operates on a tick-based model with an idle sleep of 15 seconds [crates/palyra-daemon/src/cron.rs#42-42](http://crates/palyra-daemon/src/cron.rs#42-42).

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Implementation Details

The scheduler identifies “due” jobs by querying the journal_cron_jobs table for entries where next_run_at_unix_ms is in the past. It processes these in batches of up to 64 [crates/palyra-daemon/src/cron.rs#43-43](http://crates/palyra-daemon/src/cron.rs#43-43).
  • Loopback Dispatch: Jobs are dispatched via a loopback call to the GatewayService. This ensures that cron-initiated runs go through the same message routing, policy evaluation, and sandbox execution pipeline as user-initiated messages [crates/palyra-daemon/src/cron.rs#29-33](http://crates/palyra-daemon/src/cron.rs#29-33).
  • Identity: System-initiated cron jobs execute under the system:daemon principal [crates/palyra-daemon/src/cron.rs#55-55](http://crates/palyra-daemon/src/cron.rs#55-55) and use a fixed system device ID [crates/palyra-daemon/src/cron.rs#44-44](http://crates/palyra-daemon/src/cron.rs#44-44).
  • Timezones: The scheduler supports both Utc and Local timezone modes for evaluating cron expressions [crates/palyra-daemon/src/cron.rs#61-65](http://crates/palyra-daemon/src/cron.rs#61-65).

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Cron Job Lifecycle

StateDescription
PendingJob is scheduled but the next_run_at_unix_ms has not been reached.
DueCurrent time is ≥\ge next_run_at_unix_ms.
RunningThe job has been dispatched to the GatewayService and is currently active.
FinalizedThe job completed, and the next_run_at_unix_ms was recalculated based on the schedule.
Sources: [crates/palyra-daemon/src/cron.rs#1-105](http://crates/palyra-daemon/src/cron.rs#1-105), [crates/palyra-daemon/src/journal.rs#34-40](http://crates/palyra-daemon/src/journal.rs#34-40)

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Routines and Automation

Routines are higher-level abstractions built on top of the cron scheduler. While a cron job is a raw scheduling entry, a Routine includes metadata for delivery, quiet hours, and approval policies.

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Routine Configuration

Routines are managed via the RoutineMetadataRecord [crates/palyra-daemon/src/routines.rs#188-203](http://crates/palyra-daemon/src/routines.rs#188-203). Key attributes include:
  • Trigger Kind: Supports Schedule, Hook, Webhook, SystemEvent, and Manual [crates/palyra-daemon/src/routines.rs#35-41](http://crates/palyra-daemon/src/routines.rs#35-41).
  • Delivery Mode: Determines where the output is sent: SameChannel, SpecificChannel, LocalOnly, or LogsOnly [crates/palyra-daemon/src/routines.rs#69-74](http://crates/palyra-daemon/src/routines.rs#69-74).
  • Quiet Hours: Defines a window (start/end minute of day) during which the routine will not trigger [crates/palyra-daemon/src/routines.rs#167-172](http://crates/palyra-daemon/src/routines.rs#167-172).
  • Approval Policy: Can require approval BeforeEnable or BeforeFirstRun [crates/palyra-daemon/src/routines.rs#125-129](http://crates/palyra-daemon/src/routines.rs#125-129).

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Code Entity Mapping: Routine Logic

Title: Routine Entity Relationship Sources: [crates/palyra-daemon/src/routines.rs#1-203](http://crates/palyra-daemon/src/routines.rs#1-203), [crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#53-107](http://crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#53-107)

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Misfire and Concurrency Policies

The scheduler handles edge cases where the daemon might have been offline or multiple jobs overlap.

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Misfire Policies

Defined in CronMisfirePolicy [crates/palyra-daemon/src/journal.rs#35-35](http://crates/palyra-daemon/src/journal.rs#35-35):
  1. Fire Once: If multiple runs were missed, only trigger one run immediately and then resume the schedule.
  2. Ignore: Skip all missed runs and wait for the next scheduled time.

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Concurrency Policies

Defined in CronConcurrencyPolicy [crates/palyra-daemon/src/journal.rs#35-35](http://crates/palyra-daemon/src/journal.rs#35-35):
  1. Allow: Multiple instances of the same job can run simultaneously.
  2. Forbid: If a previous instance is still running, the new trigger is skipped.
  3. Replace: The running instance is cancelled, and the new one starts.
Sources: [crates/palyra-daemon/src/cron.rs#34-40](http://crates/palyra-daemon/src/cron.rs#34-40), [crates/palyra-daemon/src/journal.rs#34-40](http://crates/palyra-daemon/src/journal.rs#34-40)

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Background Maintenance Tasks

The scheduler loop is responsible for several internal system health routines that do not appear as user-visible cron jobs.

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Skill Re-audit Task

To ensure security posture remains current, the daemon periodically re-audits installed WASM skills against the trust store.
  • Interval: Default is 6 hours [crates/palyra-daemon/src/cron.rs#54-54](http://crates/palyra-daemon/src/cron.rs#54-54).
  • Mechanism: Iterates through the InstalledSkillsIndex [crates/palyra-daemon/src/cron.rs#107-111](http://crates/palyra-daemon/src/cron.rs#107-111) and calls audit_skill_artifact_security [crates/palyra-daemon/src/cron.rs#18-18](http://crates/palyra-daemon/src/cron.rs#18-18).

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Memory Maintenance

The memory system requires periodic background processing to maintain performance and relevance.
  • Vacuuming: Triggered every 5 minutes (MEMORY_MAINTENANCE_INTERVAL) [crates/palyra-daemon/src/cron.rs#56-56](http://crates/palyra-daemon/src/cron.rs#56-56). This performs SQLite VACUUM and cleanups.
  • Embeddings Backfill: Triggered every 10 minutes [crates/palyra-daemon/src/cron.rs#57-57](http://crates/palyra-daemon/src/cron.rs#57-57). It processes items missing vector embeddings in batches of 64 [crates/palyra-daemon/src/cron.rs#58-58](http://crates/palyra-daemon/src/cron.rs#58-58).
Title: Background Task Execution Sources: [crates/palyra-daemon/src/cron.rs#42-58](http://crates/palyra-daemon/src/cron.rs#42-58), [crates/palyra-daemon/src/transport/http/handlers/console/system.rs#140-149](http://crates/palyra-daemon/src/transport/http/handlers/console/system.rs#140-149)

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HTTP Handlers and CLI Integration

Routines and Cron jobs are managed via the Console API and the palyra cron CLI command.

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Console API Routes

The routines handlers in axum manage the persistence of routine definitions:
  • GET /console/v1/routines: Lists routines with filters for trigger_kind, enabled, and channel [crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#154-182](http://crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#154-182).
  • POST /console/v1/routines/upsert: Creates or updates a routine, including its schedule and delivery config [crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#53-107](http://crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#53-107).
  • POST /console/v1/routines/dispatch: Manually triggers a routine execution [crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#125-134](http://crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#125-134).

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CLI Commands

The CLI maps these HTTP endpoints to user commands:
  • palyra cron add: Builds a ScheduleRoutineConfig and calls the upsert handler [crates/palyra-cli/src/commands/cron.rs#51-89](http://crates/palyra-cli/src/commands/cron.rs#51-89).
  • palyra cron status: Retrieves a summary of scheduled tasks and their next run times [crates/palyra-cli/src/commands/cron.rs#23-34](http://crates/palyra-cli/src/commands/cron.rs#23-34).
Sources: [crates/palyra-cli/src/commands/cron.rs#14-173](http://crates/palyra-cli/src/commands/cron.rs#14-173), [crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#1-215](http://crates/palyra-daemon/src/transport/http/handlers/console/routines.rs#1-215)