Task 61 — Local-first degradation

Phase: 6 Initiative: 42 Status: done Owner: — Slug: local-degradation

Goal

Когда cloud LLM, peers или сеть недоступны, агент следует configured safe fallback: deterministic rules, local skills, reduced-capability models, queued work, operator notification.

Acceptance criteria

• Define degradation modes enum (Offline, Degraded, Full)
• Create DegradationManager with health-check orchestration
• Implement DeterministicFallbackEngine for rule-based decisions
• Implement SafeFallbackStrategies: local skills, reduced-capability models, queued work
• Add operator notification system (webhook/email/telegram)
• Add degradation state observability (metrics, logs, status endpoint)
• Create degradation configuration schema (appsettings.json)
• Add unit tests for fallback logic
• Document degradation behavior in README

Scope / Likely files

src/agent/Degradation/

Dependencies

• блокирует / опирается на: task_004 — multi-provider-llm
• блокирует / опирается на: task_022 — semantic-routing
• блокирует / опирается на: task_060 — offline-resilience

Implementation notes

• Created src/agent/Degradation/ directory with:
  • DegradationMode.cs - enum and record types for mode/health/status
  • DegradationConfig.cs - configuration for health checks, fallback, notifications, observability
  • DegradationManager.cs - BackgroundService orchestrating health checks and mode transitions
  • DeterministicFallbackEngine.cs - rule-based fallback strategy selection
  • OperatorNotificationService.cs - webhook/Telegram/email notifications
  • DegradationObservability.cs - metrics, logging, status reports
• Updated AppConfig.cs with DegradationConfig property
• Updated Program.cs with DI registration
• Added unit tests in tests/Hercules.Agent.Tests/Degradation/DegradationTests.cs (19 tests passing)

Validation

• Build: dotnet build src/agent/Hercules.csproj - succeeded
• Tests: dotnet test --filter DegradationTests - 19 passed

Risks / Rollback

Неожиданная silent degradation; явный mode flag + observability.

Links

• Backlog: ../backlog.md
• Roadmap (EN): ../../ROADMAP-EN.md
• Roadmap (RU): ../../ROADMAP-RU.md