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docs/content/stories/epic6/6.1-enhanced-observability.md

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+# Story 6.1: Enhanced Observability
+
+## Metadata
+- **Story ID**: 6.1
+- **Title**: Enhanced Observability
+- **Epic**: 6 - Observability & Production Readiness
+- **Status**: Pending
+- **Priority**: High
+- **Estimated Time**: 6-8 hours
+- **Dependencies**: 1.6, 5.2, 5.1
+
+## Goal
+Enhance observability with full OpenTelemetry integration, comprehensive Prometheus metrics expansion, and improved logging with request correlation.
+
+## Description
+This story enhances the observability system by completing OpenTelemetry integration with all infrastructure components, expanding Prometheus metrics, and improving logging with better correlation and structured fields.
+
+## Deliverables
+
+### 1. Complete OpenTelemetry Integration
+- Export traces to Jaeger/OTLP collector
+- Add database instrumentation (Ent interceptor)
+- Add Kafka instrumentation
+- Add Redis instrumentation
+- Create custom spans:
+  - Module initialization spans
+  - Background job spans
+  - Event publishing spans
+- Trace context propagation:
+  - Include trace ID in logs
+  - Propagate across HTTP calls
+  - Include in error reports
+
+### 2. Prometheus Metrics Expansion
+- Add more metrics:
+  - Database connection pool stats
+  - Cache hit/miss ratio
+  - Event bus publish/consume rates
+  - Background job execution times
+  - Module-specific metrics (via module interface)
+- Create metric labels:
+  - `module` label for module metrics
+  - `tenant_id` label (if multi-tenant)
+  - `status` label for error rates
+
+### 3. Enhanced Logging
+- Add structured fields:
+  - `user_id` from context
+  - `tenant_id` from context
+  - `module` name for module logs
+  - `trace_id` from OpenTelemetry
+- Create log aggregation config:
+  - JSON format for production
+  - Human-readable for development
+  - Support for Loki/CloudWatch/ELK
+
+## Acceptance Criteria
+- [ ] Traces are exported and visible in Jaeger
+- [ ] All infrastructure components are instrumented
+- [ ] Trace IDs are included in logs
+- [ ] Metrics are expanded with new dimensions
+- [ ] Logs include all correlation fields
+- [ ] Log aggregation works correctly
+
+## Files to Create/Modify
+- `internal/observability/tracer.go` - Enhanced tracing
+- `internal/infra/database/client.go` - Add tracing
+- `internal/infra/cache/redis_cache.go` - Add tracing
+- `internal/infra/bus/kafka_bus.go` - Add tracing
+- `internal/metrics/metrics.go` - Expanded metrics
+- `internal/logger/zap_logger.go` - Enhanced logging
+