Multi-agent application documentation

docs/agents.md

@@ -108,7 +108,7 @@ You can also pass messages from previous runs to continue a conversation or prov
 
 #### Usage Limits
 
-PydanticAI offers a [`settings.UsageLimits`][pydantic_ai.settings.UsageLimits] structure to help you limit your
+PydanticAI offers a [`UsageLimits`][pydantic_ai.usage.UsageLimits] structure to help you limit your
 usage (tokens and/or requests) on model runs.
 
 You can apply these settings by passing the `usage_limits` argument to the `run{_sync,_stream}` functions.
@@ -118,7 +118,7 @@ Consider the following example, where we limit the number of response tokens:
 ```py
 from pydantic_ai import Agent
 from pydantic_ai.exceptions import UsageLimitExceeded
-from pydantic_ai.settings import UsageLimits
+from pydantic_ai.usage import UsageLimits
 
 agent = Agent('claude-3-5-sonnet-latest')
 
@@ -150,7 +150,7 @@ from typing_extensions import TypedDict
 
 from pydantic_ai import Agent, ModelRetry
 from pydantic_ai.exceptions import UsageLimitExceeded
-from pydantic_ai.settings import UsageLimits
+from pydantic_ai.usage import UsageLimits
 
 
 class NeverResultType(TypedDict):

docs/api/usage.md

@@ -0,0 +1,3 @@
+# `pydantic_ai.usage`
+
+::: pydantic_ai.usage

docs/dependencies.md

@@ -275,6 +275,8 @@ async def application_code(prompt: str) -> str:  # (3)!
 3. Application code that calls the agent, in a real application this might be an API endpoint.
 4. Call the agent from within the application code, in a real application this call might be deep within a call stack. Note `app_deps` here will NOT be used when deps are overridden.
 
+_(This example is complete, it can be run "as is")_
+
 ```python {title="test_joke_app.py" hl_lines="10-12" call_name="test_application_code"}
 from joke_app import MyDeps, application_code, joke_agent
 
@@ -296,44 +298,6 @@ async def test_application_code():
 3. Override the dependencies of the agent for the duration of the `with` block, `test_deps` will be used when the agent is run.
 4. Now we can safely call our application code, the agent will use the overridden dependencies.
 
-## Agents as dependencies of other Agents
-
-Since dependencies can be any python type, and agents are just python objects, agents can be dependencies of other agents.
-
-```python {title="agents_as_dependencies.py"}
-from dataclasses import dataclass
-
-from pydantic_ai import Agent, RunContext
-
-
-@dataclass
-class MyDeps:
-    factory_agent: Agent[None, list[str]]
-
-
-joke_agent = Agent(
-    'openai:gpt-4o',
-    deps_type=MyDeps,
-    system_prompt=(
-        'Use the "joke_factory" to generate some jokes, then choose the best. '
-        'You must return just a single joke.'
-    ),
-)
-
-factory_agent = Agent('gemini-1.5-pro', result_type=list[str])
-
-
-@joke_agent.tool
-async def joke_factory(ctx: RunContext[MyDeps], count: int) -> str:
-    r = await ctx.deps.factory_agent.run(f'Please generate {count} jokes.')
-    return '\n'.join(r.data)
-
-
-result = joke_agent.run_sync('Tell me a joke.', deps=MyDeps(factory_agent))
-print(result.data)
-#> Did you hear about the toothpaste scandal? They called it Colgate.
-```
-
 ## Examples
 
 The following examples demonstrate how to use dependencies in PydanticAI:

docs/examples/flight-booking.md

@@ -0,0 +1,41 @@
+Example of a multi-agent flow where one agent delegates work to another, then hands off control to a third agent.
+
+Demonstrates:
+
+* [agent delegation](../multi-agent-applications.md#agent-delegation)
+* [programmatic agent hand-off](../multi-agent-applications.md#programmatic-agent-hand-off)
+* [usage limits](../agents.md#usage-limits)
+
+In this scenario, a group of agents work together to find the best flight for a user.
+
+The control flow for this example can be summarised as follows:
+
+```mermaid
+graph TD
+  START --> search_agent("search agent")
+  search_agent --> extraction_agent("extraction agent")
+  extraction_agent --> search_agent
+  search_agent --> human_confirm("human confirm")
+  human_confirm --> search_agent
+  search_agent --> FAILED
+  human_confirm --> find_seat_function("find seat function")
+  find_seat_function --> human_seat_choice("human seat choice")
+  human_seat_choice --> find_seat_agent("find seat agent")
+  find_seat_agent --> find_seat_function
+  find_seat_function --> buy_flights("buy flights")
+  buy_flights --> SUCCESS
+```
+
+## Running the Example
+
+With [dependencies installed and environment variables set](./index.md#usage), run:
+
+```bash
+python/uv-run -m pydantic_ai_examples.flight_booking
+```
+
+## Example Code
+
+```python {title="flight_booking.py"}
+#! examples/pydantic_ai_examples/flight_booking.py
+```

docs/extra/tweaks.css

@@ -55,3 +55,7 @@ img.index-header {
   min-height: 120px;
   margin-bottom: 10px;
 }
+
+.mermaid {
+  text-align: center;
+}