Files
Evan Mattson 9b22ecd119 Python: Add requirements.txt and .env.example to the a2a/ sample for pip-based setup (#5510)
* Add requirements.txt and .env.example to a2a sample

Beginners following the a2a/ sample had no pip-based install path:
the directory lacked requirements.txt and .env.example, unlike every
other 04-hosting/ sample.

- Add requirements.txt with editable local package paths matching the
  pattern used in azure_functions/ and similar hosting samples
- Add .env.example documenting FOUNDRY_PROJECT_ENDPOINT, FOUNDRY_MODEL,
  and A2A_AGENT_HOST
- Update README Quick Start to cover both pip (.venv) and uv workflows

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Python: Add `requirements.txt` and `.env.example` to the `a2a/` sample for pip-based setup

Fixes #5395

* fix(a2a-sample): address PR review feedback for issue #5395

- Remove 'from repo root' wording from Option B uv heading in README
  to avoid contradicting the 'run from this directory' instruction
- Fix A2A_AGENT_HOST default in .env.example from 5001 to 5000 to match
  function-tools flow; add clarifying comments about port usage
- Add note for pip users explaining they can replace 'uv run python'
  with 'python' once the virtual environment is activated

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Address review feedback for #5395: Python: [Samples][Python] a2a/ sample missing requirements.txt — beginners cannot install dependencies

---------

Co-authored-by: Copilot <copilot@github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
2026-04-27 22:22:07 +00:00

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Markdown

# A2A Agent Examples
This sample demonstrates how to host and consume agents using the [A2A (Agent2Agent) protocol](https://a2a-protocol.org/latest/) with the `agent_framework` package. There are three runnable entry points:
| Run this file | To... |
|---------------|-------|
| **[`a2a_server.py`](a2a_server.py)** | Host an Agent Framework agent as an A2A-compliant server. |
| **[`agent_with_a2a.py`](agent_with_a2a.py)** | Connect to an A2A server and send requests (non-streaming and streaming). |
| **[`a2a_agent_as_function_tools.py`](a2a_agent_as_function_tools.py)** | Convert A2A agent skills into function tools for a host agent. |
The remaining files are supporting modules used by the server:
| File | Description |
|------|-------------|
| [`agent_framework_to_a2a.py`](agent_framework_to_a2a.py) | Exposes an agent_framework agent as an A2A-compliant server. Demonstrates how to wrap an agent_framework agent and expose it as an A2A service that other A2A clients can discover and communicate with. |
| [`agent_definitions.py`](agent_definitions.py) | Agent and AgentCard factory definitions for invoice, policy, and logistics agents. |
| [`agent_executor.py`](agent_executor.py) | Bridges the a2a-sdk `AgentExecutor` interface to Agent Framework agents. |
| [`invoice_data.py`](invoice_data.py) | Mock invoice data and tool functions for the invoice agent. |
| [`a2a_server.http`](a2a_server.http) | REST Client requests for testing the server directly from VS Code. |
## Environment Variables
Make sure to set the following environment variables before running the examples:
### Required (Server)
- `FOUNDRY_PROJECT_ENDPOINT` — Your Azure AI Foundry project endpoint
- `FOUNDRY_MODEL` — Model deployment name (e.g. `gpt-4o`)
### Required (Client)
- `A2A_AGENT_HOST` — URL of the A2A server (e.g. `http://localhost:5001/`)
### Required (Function Tools Sample)
- `A2A_AGENT_HOST` — URL of the A2A server (e.g. `http://localhost:5000/`)
- `FOUNDRY_PROJECT_ENDPOINT` — Your Azure AI Foundry project endpoint
- `FOUNDRY_MODEL` — Model deployment name (e.g. `gpt-4o`)
## Quick Start
All commands below should be run from this directory:
```powershell
cd python/samples/04-hosting/a2a
```
### 0. Install Dependencies
Copy `.env.example` to `.env` and fill in your values:
```powershell
copy .env.example .env
```
**Option A — pip (standard):**
```powershell
python -m venv .venv
.venv\Scripts\Activate.ps1 # Windows
# source .venv/bin/activate # macOS / Linux
pip install -r requirements.txt
```
**Option B — uv:**
```powershell
uv run python a2a_server.py --agent-type policy
```
### 1. Start the A2A Server
> **Note (Option A — pip users):** Replace `uv run python` with `python` in all `uv run` commands below (e.g. `python a2a_server.py ...`). `uv` is not required once the virtual environment is activated.
Pick an agent type and start the server (each in its own terminal):
```powershell
uv run python a2a_server.py --agent-type invoice --port 5000
uv run python a2a_server.py --agent-type policy --port 5001
uv run python a2a_server.py --agent-type logistics --port 5002
```
You can run one agent or all three — each listens on its own port.
### 2. Run the A2A Client
In a separate terminal (from the same directory), point the client at a running server:
```powershell
$env:A2A_AGENT_HOST = "http://localhost:5001/"
uv run python agent_with_a2a.py
# A2A server exposing an agent_framework agent
uv run python agent_framework_to_a2a.py
```
### 3. Run the Function Tools Sample
This sample resolves the remote agent's skills and registers each one as a function tool
on a host Foundry-backed agent. The host agent then autonomously selects the right skill
to handle the user's request.
```powershell
$env:A2A_AGENT_HOST = "http://localhost:5000/"
uv run python a2a_agent_as_function_tools.py
```