llama-stack/docs/source/building_applications/agent.md
Francisco Arceo 23a99a4b22
docs: Minor updates to docs to make them a little friendlier to new users (#1871)
# What does this PR do?
This PR modifies some of the docs to help them map to (1) the mental
model of software engineers building AI models starting with RAG and
then moving to Agents and (2) aligning the navbar somewhat closer to the
diagram on the home page.

## Test Plan
N/A Tested locally.

# Documentation
Take a look at the screen shot for below and after.
## Before 
![Screenshot 2025-04-03 at 10 39
32 PM](https://github.com/user-attachments/assets/c4dc9998-3e46-43b0-8425-892c94ec3a6a)

## After
![Screenshot 2025-04-03 at 10 38
37 PM](https://github.com/user-attachments/assets/05670fcd-e56b-42dd-8af2-07b81f941d40)

---------

Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>
2025-04-04 08:10:35 -04:00

92 lines
2.5 KiB
Markdown

# Agents
An Agent in Llama Stack is a powerful abstraction that allows you to build complex AI applications.
The Llama Stack agent framework is built on a modular architecture that allows for flexible and powerful AI
applications. This document explains the key components and how they work together.
## Core Concepts
### 1. Agent Configuration
Agents are configured using the `AgentConfig` class, which includes:
- **Model**: The underlying LLM to power the agent
- **Instructions**: System prompt that defines the agent's behavior
- **Tools**: Capabilities the agent can use to interact with external systems
- **Safety Shields**: Guardrails to ensure responsible AI behavior
```python
from llama_stack_client import Agent
# Create the agent
agent = Agent(
llama_stack_client,
model="meta-llama/Llama-3-70b-chat",
instructions="You are a helpful assistant that can use tools to answer questions.",
tools=["builtin::code_interpreter", "builtin::rag/knowledge_search"],
)
```
### 2. Sessions
Agents maintain state through sessions, which represent a conversation thread:
```python
# Create a session
session_id = agent.create_session(session_name="My conversation")
```
### 3. Turns
Each interaction with an agent is called a "turn" and consists of:
- **Input Messages**: What the user sends to the agent
- **Steps**: The agent's internal processing (inference, tool execution, etc.)
- **Output Message**: The agent's response
```python
from llama_stack_client import AgentEventLogger
# Create a turn with streaming response
turn_response = agent.create_turn(
session_id=session_id,
messages=[{"role": "user", "content": "Tell me about Llama models"}],
)
for log in AgentEventLogger().log(turn_response):
log.print()
```
### Non-Streaming
```python
from rich.pretty import pprint
# Non-streaming API
response = agent.create_turn(
session_id=session_id,
messages=[{"role": "user", "content": "Tell me about Llama models"}],
stream=False,
)
print("Inputs:")
pprint(response.input_messages)
print("Output:")
pprint(response.output_message.content)
print("Steps:")
pprint(response.steps)
```
### 4. Steps
Each turn consists of multiple steps that represent the agent's thought process:
- **Inference Steps**: The agent generating text responses
- **Tool Execution Steps**: The agent using tools to gather information
- **Shield Call Steps**: Safety checks being performed
## Agent Execution Loop
Refer to the [Agent Execution Loop](agent_execution_loop) for more details on what happens within an agent turn.