> ## Documentation Index
> Fetch the complete documentation index at: https://phidatainc.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# AgentOS Demo

> Share one PostgresDb across AgentOS and its agent as the default database, with PgVector knowledge and the Agno MCP server.

Authentication is optional. Set `OS_SECURITY_KEY` to enable it for this AgentOS.

```python agentos_default_db.py theme={null}
"""
AgentOS Demo

Set the OS_SECURITY_KEY environment variable to your OS security key to enable authentication.

Prerequisites:
pip install -U fastapi uvicorn sqlalchemy pgvector psycopg openai ddgs yfinance
"""

from agno.agent import Agent
from agno.db.postgres import PostgresDb
from agno.knowledge.knowledge import Knowledge
from agno.models.openai import OpenAIChat
from agno.os import AgentOS
from agno.tools.mcp import MCPTools
from agno.vectordb.pgvector import PgVector

# ---------------------------------------------------------------------------
# Create Example
# ---------------------------------------------------------------------------

# Database connection
db_url = "postgresql+psycopg://ai:ai@localhost:5532/ai"

# Create Postgres-backed memory store
db = PostgresDb(db_url=db_url)

# Create Postgres-backed vector store
vector_db = PgVector(
    db_url=db_url,
    table_name="agno_docs",
)
knowledge = Knowledge(
    name="Agno Docs",
    contents_db=db,
    vector_db=vector_db,
)

# Create your agents
agno_agent = Agent(
    name="Agno Agent",
    model=OpenAIChat(id="gpt-4.1"),
    tools=[MCPTools(transport="streamable-http", url="https://docs.agno.com/mcp")],
    knowledge=knowledge,
    markdown=True,
)

# Create the AgentOS
agent_os = AgentOS(
    id="agentos-demo",
    agents=[agno_agent],
    db=db,  # This is the default database for AgentOS, the agno_agent will use this
)
app = agent_os.get_app()


# ---------------------------------------------------------------------------
# Run Example
# ---------------------------------------------------------------------------

if __name__ == "__main__":
    agent_os.serve(app="agentos_default_db:app", port=7777, reload=True)
```

## Run the Example

<Steps>
  <Snippet file="create-venv-step.mdx" />

  <Step title="Install dependencies">
    ```bash theme={null}
    uv pip install -U "agno[mcp,os]" "psycopg[binary]" openai pgvector
    ```
  </Step>

  <Step title="Export your OpenAI API key">
    <CodeGroup>
      ```bash Mac/Linux theme={null}
      export OPENAI_API_KEY="your_openai_api_key_here"
      ```

      ```bash Windows theme={null}
      $Env:OPENAI_API_KEY="your_openai_api_key_here"
      ```
    </CodeGroup>
  </Step>

  <Snippet file="run-pgvector-step.mdx" />

  <Step title="Optional: enable authentication">
    Set `OS_SECURITY_KEY` before running to require AgentOS authentication. Leave it unset to run without authentication.
  </Step>

  <Step title="Run the example">
    Save the code above as `agentos_default_db.py`, then run:

    ```bash theme={null}
    python agentos_default_db.py
    ```
  </Step>
</Steps>

Full source: [cookbook/05\_agent\_os/dbs/agentos\_default\_db.py](https://github.com/agno-agi/agno/blob/main/cookbook/05_agent_os/dbs/agentos_default_db.py)