sequenceDiagram
    participant Client
    participant API as FastAPI Backend
    participant Strategy as Strategy Services
    participant Graph as Neo4j
    participant Redis as Redis
    participant Chroma as ChromaDB
    participant Ollama as Ollama
    participant DID as D-ID
    participant Hume as Hume

    Client->>API: GET /healthz
    API-->>Client: status ok

    Client->>API: POST /api/pipeline/seed
    API->>Graph: ingest doctors
    Graph-->>API: seeded result
    API-->>Client: graph ready

    Client->>API: POST /api/strategy/full-evaluate
    API->>Strategy: load records and cluster
    Strategy->>Ollama: feature extraction or optimization if configured
    Strategy->>Chroma: retrieve campaign examples if needed
    Strategy-->>API: heatmap and cluster result
    API-->>Client: strategy response

    Client->>API: GET /api/strategy/cluster/{cluster_id}/doctors
    API-->>Client: doctors in chosen segment

    Client->>API: GET /api/persona/{code_name}
    API->>Graph: doctor lookup
    Graph-->>API: doctor data or empty
    API-->>Client: persona payload

    Client->>API: POST /api/simulation/start
    API->>DID: create stream if configured
    API->>Redis: store session
    API-->>Client: session and stream details

    Client->>API: POST /api/simulation/turn
    API->>Redis: read and update session
    API->>Chroma: semantic cache lookup
    API->>Ollama: generate reply if needed
    API->>Hume: analyze prosody if audio present
    API-->>Client: simulation response

    Client->>API: POST /api/mohp/evaluate
    API->>Ollama: generate objections if configured
    API->>Redis: store objections
    API-->>Client: objections

    Client->>API: GET /api/analytics/session/{session_id}
    API->>Redis: load session analytics
    API-->>Client: full review