Python: Foundry hosted agent V2 (#5379)

* Python: Wrapper + Samples 1st (#5177)

* Experiment

* Update dependency and add non streaming

* Add more samples

* Rename samples

* Add invocations

* Comments 1

* Comments 2

* Comments 3

* Improve README

* Add local shell sample

* WIP: Add eval and memory samples

* Update user agent prefix

* Update user agent prefix doc

* Update dependency (#5215)

* Add tests and more content types (#5235)

* Add tests

* fix tests and sample

* Fix formatting

* Remove function approval contents

* Python: Refine samples and upgrade packages (#5261)

* Refine samples and upgrade pacakges

* Upgrade to a new package that fixes a bug

* Update model env var

* Move samples (#5281)

* Python: Upgrade agentserver packages (#5284)

* Upgrade agentserver packages

* Fix new types

* Python: Add special handling for workflows (#5298)

* Add special handling for workflows

* Address comments

* Improve samples (#5372)

* Python: Add more types (#5378)

* Add more type supports

* Upgrade packages

* Remove TODOs in README

* Fix README

* Comments and mypy

* User agent scoped

* Fix README

* Fix pre commit

* Fix pre commit 2

* Fix pre commit 3

* Fix pre commit 4

* Fix pre commit 5

* Fix pre commit 6

* Add azure-monitor-opentelemetry to dev deps

Fixes Samples & Markdown CI failure. The PR's new transitive dep on
azure-monitor-opentelemetry-exporter (via azure-ai-agentserver-core) makes
pyright resolve the azure.monitor.opentelemetry namespace, flipping the
check_md_code_blocks diagnostic for `configure_azure_monitor` from
reportMissingImports (filtered) to reportAttributeAccessIssue (not filtered).
Installing the umbrella azure-monitor-opentelemetry package in dev makes
pyright resolve the symbol correctly, matching the install guidance the
observability README already gives users.

---------

Co-authored-by: Evan Mattson <evan.mattson@microsoft.com>

python/packages/core/agent_framework/_telemetry.py

@@ -4,6 +4,9 @@ from __future__ import annotations
 
 import logging
 import os
+from collections.abc import Generator
+from contextlib import contextmanager
+from contextvars import ContextVar
 from typing import Any, Final
 
 from . import __version__ as version_info
@@ -26,6 +29,35 @@ USER_AGENT_KEY: Final[str] = "User-Agent"
 HTTP_USER_AGENT: Final[str] = "agent-framework-python"
 AGENT_FRAMEWORK_USER_AGENT = f"{HTTP_USER_AGENT}/{version_info}"  # type: ignore[has-type]
 
+_user_agent_prefixes: ContextVar[tuple[str, ...]] = ContextVar("_user_agent_prefixes", default=())
+
+
+@contextmanager
+def user_agent_prefix(prefix: str) -> Generator[None]:
+    """Context manager that adds a prefix to the user agent string for the current scope.
+
+    This is useful for upstream layers that want to identify themselves in telemetry
+    for the duration of a request without permanently mutating global state.
+
+    Args:
+        prefix: The prefix to add (e.g. "foundry-hosting").
+    """
+    current = _user_agent_prefixes.get()
+    token = _user_agent_prefixes.set((*current, prefix)) if prefix and prefix not in current else None
+    try:
+        yield
+    finally:
+        if token is not None:
+            _user_agent_prefixes.reset(token)
+
+
+def _get_user_agent() -> str:
+    """Return the full user agent string including any context-scoped prefixes."""
+    prefixes = _user_agent_prefixes.get()
+    if not prefixes:
+        return AGENT_FRAMEWORK_USER_AGENT
+    return f"{'/'.join(prefixes)}/{AGENT_FRAMEWORK_USER_AGENT}"
+
 
 def prepend_agent_framework_to_user_agent(headers: dict[str, Any] | None = None) -> dict[str, Any]:
     """Prepend "agent-framework" to the User-Agent in the headers.
@@ -57,12 +89,9 @@ def prepend_agent_framework_to_user_agent(headers: dict[str, Any] | None = None)
     """
     if not IS_TELEMETRY_ENABLED:
         return headers or {}
+    user_agent = _get_user_agent()
     if not headers:
-        return {USER_AGENT_KEY: AGENT_FRAMEWORK_USER_AGENT}
-    headers[USER_AGENT_KEY] = (
-        f"{AGENT_FRAMEWORK_USER_AGENT} {headers[USER_AGENT_KEY]}"
-        if USER_AGENT_KEY in headers
-        else AGENT_FRAMEWORK_USER_AGENT
-    )
+        return {USER_AGENT_KEY: user_agent}
+    headers[USER_AGENT_KEY] = f"{user_agent} {headers[USER_AGENT_KEY]}" if USER_AGENT_KEY in headers else user_agent
 
     return headers

python/packages/core/tests/core/test_telemetry.py

@@ -8,6 +8,7 @@ from agent_framework import (
     USER_AGENT_TELEMETRY_DISABLED_ENV_VAR,
     prepend_agent_framework_to_user_agent,
 )
+from agent_framework._telemetry import user_agent_prefix
 
 # region Test constants
 
@@ -96,3 +97,56 @@ def test_modifies_original_dict():
 
     assert result is headers  # Same object
     assert "User-Agent" in headers
+
+
+# region Test user_agent_prefix context manager
+
+
+def test_user_agent_prefix_adds_prefix():
+    """Test that the context manager adds a prefix within its scope."""
+    with user_agent_prefix("test-host"):
+        result = prepend_agent_framework_to_user_agent()
+        assert result["User-Agent"].startswith("test-host/")
+        assert AGENT_FRAMEWORK_USER_AGENT in result["User-Agent"]
+
+    # Prefix is removed after exiting the context
+    result = prepend_agent_framework_to_user_agent()
+    assert result["User-Agent"] == AGENT_FRAMEWORK_USER_AGENT
+
+
+def test_user_agent_prefix_ignores_duplicates():
+    """Test that duplicate prefixes are not added within nested scopes."""
+    with user_agent_prefix("test-host"), user_agent_prefix("test-host"):
+        result = prepend_agent_framework_to_user_agent()
+        assert result["User-Agent"].count("test-host") == 1
+
+
+def test_user_agent_prefix_ignores_empty():
+    """Test that empty strings are not added as prefixes."""
+    with user_agent_prefix(""):
+        result = prepend_agent_framework_to_user_agent()
+        assert result["User-Agent"] == AGENT_FRAMEWORK_USER_AGENT
+
+
+def test_user_agent_prefix_restores_on_exit():
+    """Test that prefixes are fully restored after the context manager exits."""
+    with user_agent_prefix("test-host"):
+        pass
+    result = prepend_agent_framework_to_user_agent()
+    assert result["User-Agent"] == AGENT_FRAMEWORK_USER_AGENT
+
+
+def test_user_agent_prefix_nesting():
+    """Test that nested context managers compose prefixes correctly."""
+    with user_agent_prefix("outer"):
+        with user_agent_prefix("inner"):
+            result = prepend_agent_framework_to_user_agent()
+            assert "outer" in result["User-Agent"]
+            assert "inner" in result["User-Agent"]
+        # Inner prefix removed
+        result = prepend_agent_framework_to_user_agent()
+        assert "outer" in result["User-Agent"]
+        assert "inner" not in result["User-Agent"]
+    # Both removed
+    result = prepend_agent_framework_to_user_agent()
+    assert result["User-Agent"] == AGENT_FRAMEWORK_USER_AGENT