A2A-Protocol-with-Neo4j

# A2A Protocol with Neo4j This repo hosts three collaborating agents built on the A2A protocol and Google ADK: - **Movie Agent** — answers movie recommendation queries backed by Neo4j. - **Sushmita Agent** — shares availability, favorite genres, and already‑watched movies. - **Host Agent** — coordinates between the two agents to propose a movie plan (asks availability only when requested), then can confirm/cancel plans. ## Prerequisites - Python 3.10+ - Neo4j database accessible from your machine - API access for Gemini (via `GOOGLE_API_KEY`) or Vertex (`GOOGLE_GENAI_USE_VERTEXAI=TRUE`) ## Environment Create a `.env` (at repo root) with: ``` GOOGLE_API_KEY=your_api_key # required if not using Vertex GOOGLE_GENAI_USE_VERTEXAI=FALSE # set TRUE to skip API key check NEO4J_URI=bolt://localhost:7687 NEO4J_USERNAME=neo4j NEO4J_PASSWORD=your_password NEO4J_DATABASE=neo4j # or your database name HOST_OVERRIDE= # optional override for Sushmita Agent card URL ``` ## Install ``` pip install -r requirements.txt ``` ## Run the agents Start each agent in its own terminal: ``` # Movie Agent (port 10005) uv run --active . # Sushmita Agent (port 10006) uv run --active . ``` The Host Agent is a coordinating runner (no HTTP server here) and targets the above agents at: ``` http://localhost:10005 # Movie Agent http://localhost:10006 # Sushmita Agent ``` uv run --active adk web If you change ports, update `friend_agent_urls` in `host_agent/host/agent.py`. ## Neo4j usage notes - The Movie Agent opens a Neo4j driver per request and closes it reliably. - Queries are parameterized (e.g., `MATCH (m:Movie)-[:IN_GENRE]->(g:Genre {name: $genre})`). - Ensure the Movie graph (Movie, Genre, Person, ACTED_IN, DIRECTED, IN_GENRE) exists in your database. ## Troubleshooting - **Driver closed**: confirm `NEO4J_URI/USERNAME/PASSWORD/DATABASE` are correct and Neo4j is reachable. - **Task not found between agents**: Host Agent now generates fresh task/context IDs per message; ensure agents are running on the configured ports. - **Missing API key**: set `GOOGLE_API_KEY` or `GOOGLE_GENAI_USE_VERTEXAI=TRUE`. ## Key entry points - `movie_agent/__main__.py` — starts Movie Agent (port 10005) - `sushmita_agent/__main__.py` — starts Sushmita Agent (port 10006) - `host_agent/host/agent.py` — Host Agent runner coordinating both agents