What should a complete large-scale Agent system look like? A battle-tested architecture blueprint, module design, code skeletons, and engineering practices. Copy it, modify it, surpass it.
From UX layer to infrastructure, each has clear responsibilities and interfaces.
Layered architecture separates concerns. Each layer can be tested, replaced, and extended independently.
graph TB
subgraph UX["🎨 Layer 1 · User Experience"]
UI1[Web UI]
UI2[CLI]
UI3[API Endpoints]
end
subgraph ORCH["⚙️ Layer 2 · Orchestration"]
O1[LangGraph State Machine]
O2[Planner / Executor]
O3[Workflow Engine]
end
subgraph AGENT["🤖 Layer 3 · Agents"]
A1[Master Agent]
A2[Sub-Agent A]
A3[Sub-Agent B]
A4[Specialist Agent]
end
subgraph TOOLS["🔧 Layer 4 · Tools & Memory"]
T1[Tool Registry]
T2[Tool Implementations
SearchAPI / Database / Code]
M1[Short-term Memory]
M2[Long-term Memory
VectorDB + KG]
end
subgraph INFRA["🏗️ Layer 5 · Infrastructure"]
I1[LLM Provider
OpenAI / Anthropic / Local]
I2[Observability
LangFuse / LangSmith]
I3[Storage
Postgres + Redis]
I4[Eval Pipeline]
end
UX --> ORCH
ORCH --> AGENT
AGENT --> TOOLS
TOOLS --> INFRA
classDef ux fill:#7c5cff,stroke:#00d4ff,color:#fff,stroke-width:2px;
classDef orch fill:#00d4ff,stroke:#00ffa3,color:#000,stroke-width:2px;
classDef agent fill:#00ffa3,stroke:#7c5cff,color:#000,stroke-width:2px;
classDef tools fill:#ff6ec7,stroke:#ffb84d,color:#fff,stroke-width:2px;
classDef infra fill:#ffb84d,stroke:#ff5e7a,color:#000,stroke-width:2px;
class UX,UI1,UI2,UI3 ux;
class ORCH,O1,O2,O3 orch;
class AGENT,A1,A2,A3,A4 agent;
class TOOLS,T1,T2,M1,M2 tools;
class INFRA,I1,I2,I3,I4 infra;
Translate the five-layer architecture into code. Clear, maintainable, extensible.
my_agent/
├── 📁 src/
│ ├── 📁 agents/
│ │ ├── base.py # Agent abstract base
│ │ ├── master.py # Master Agent
│ │ ├── researcher.py # Sub-Agent
│ │ └── reviewer.py # Reviewer Agent
│ ├── 📁 orchestration/
│ │ ├── graph.py # LangGraph definition
│ │ ├── state.py # State Schema
│ │ └── router.py # Routing logic
│ ├── 📁 tools/
│ │ ├── registry.py # Tool registry
│ │ ├── search.py # Search tool
│ │ ├── database.py # DB tool
│ │ └── code_exec.py # Code execution
│ ├── 📁 memory/
│ │ ├── short_term.py
│ │ ├── long_term.py
│ │ └── hybrid.py
│ ├── 📁 prompts/
│ │ ├── master.yaml
│ │ ├── researcher.yaml
│ │ └── reviewer.yaml
│ ├── 📁 llm/
│ │ ├── providers.py
│ │ └── config.py
│ └── 📁 observability/
│ ├── tracing.py
│ └── metrics.py
├── 📁 tests/
│ ├── unit/
│ ├── integration/
│ └── eval/
├── 📁 configs/
│ ├── dev.yaml
│ └── prod.yaml
├── 📁 data/
├── 📁 notebooks/ # Exploratory experiments
├── 📄 main.py # CLI entry
├── 📄 api.py # FastAPI service
├── 📄 Dockerfile
├── 📄 pyproject.toml
└── 📄 README.md
[project]
name = "my-agent"
version = "0.1.0"
requires-python = ">=3.11"
dependencies = [
"langchain>=0.3",
"langgraph>=0.2",
"langchain-openai>=0.2",
"langchain-anthropic>=0.2",
"llama-index>=0.12",
"chromadb>=0.5",
"tiktoken",
"tenacity", # retries
"langfuse>=2.0", # observability
"pydantic>=2.7", # data validation
"pydantic-settings>=2.3",
"fastapi>=0.115",
"uvicorn>=0.32",
"structlog>=24.4",
"rich>=13.9",
"redis>=5.0",
"sqlalchemy>=2.0",
]
[project.optional-dependencies]
dev = [
"pytest>=8.3",
"pytest-asyncio>=0.24",
"pytest-cov>=5",
"ruff>=0.6",
"mypy>=1.11",
"ipython>=8.27",
"gradio>=5.0",
]
Multiple deployment paths from single-machine to cloud.
Fastest feedback loop. Development phase and single-user demos.
python main.pyConsistent environment, easy distribution. Teams and small-scale production.
FROM python:3.11-slim
WORKDIR /app
COPY pyproject.toml poetry.lock ./
RUN pip install poetry && \
poetry install --no-dev
COPY src/ ./src/
COPY main.py api.py ./
CMD ["uvicorn", "api:app", \
"--host", "0.0.0.0", \
"--port", "8000"]
Scalable, high-availability. Production environments.