Python: Fix hyperlight WasmSandbox cross-thread Drop and harden hosted-agent sample (#5603)

* update hyperlight to beta and move samples, add hosted agent sample

* Python: Fix hyperlight WasmSandbox cross-thread Drop and harden sample

Root cause: when a worker-side closure raised, the exception's __traceback__
retained frame locals that included the partially constructed PyO3 sandbox.
Future.result() re-raised that exception on the caller thread, and when the
caller's exception was eventually GC'd the frame locals were released
off-thread, dec_ref'ing the unsendable sandbox from the wrong thread and
tripping the PyO3 panic
'_native_wasm::WasmSandbox is unsendable, but is being dropped on another thread'.

Fix:
* Add _SandboxWorker._run_on_worker which catches every exception on the
  worker, drops __traceback__ there, deletes the original exception, and
  re-raises a fresh instance on the caller thread. initialize and execute
  route through it; dispose keeps its bare-submit semantics.
* Add an opt-in diagnostic module _drop_diagnostic (no-op unless
  HYPERLIGHT_TRACE_DROPS=1) that installs a sys.unraisablehook and dumps
  owner-thread + per-thread stacks on any future cross-thread unsendable
  Drop. Useful for triaging similar PyO3 regressions.
* Tests: cross-thread invocation, traceback-leak isolation, _SandboxEntry
  attribute-shape check, and a stale-reference stress test driven through
  asyncio.to_thread.

Sample (samples/04-hosting/foundry-hosted-agents/responses/06_hyperlight_codeact):
* Dockerfile installs agent-framework-* from in-tree source with python/ as
  build context so unreleased fixes can be validated end-to-end.
* call_server.py pins the Responses API version.
* main.py enables include_detailed_errors=True so future tool failures
  surface the actual exception text instead of a bare 'Error: Function
  failed.' string.
* README.md documents the in-tree-package build and the Hyperlight
  hypervisor requirement (/dev/kvm on Linux, MSHV on Windows). Hosted
  environments without hypervisor passthrough surface 'No Hypervisor was
  found for Sandbox'; this is a hosting constraint, not a hyperlight bug.

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

* Python: remove _drop_diagnostic from hyperlight package

The diagnostic module was useful while bisecting the cross-thread Drop bug,
but it is no longer needed now that _SandboxWorker._run_on_worker prevents
the panic at the source.

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

* Python: address PR review feedback on hyperlight

- Use lazy agent_framework.hyperlight import in sample main.py.
- Env-driven endpoint (FOUNDRY_AGENT_ENDPOINT) in call_server.py; remove personal URLs.
- Align agent.yaml model deployment with manifest (gpt-4.1-mini).
- Tighten Dockerfile requirements guard; drop dangling deploy.ps1 reference.
- Preserve exception args when sanitizing tracebacks in _run_on_worker.
- Add public _SandboxWorker.is_alive(); update test to avoid private attr.
- Add namespace coverage tests for agent_framework.hyperlight lazy loader.
- Add prominent note: Foundry hosted-agent runtime does not yet support
  Hyperlight (no hypervisor exposed); container works locally with /dev/kvm.

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

* Python: bump hyperlight-sandbox dependencies to 0.4.x

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

* Python: renumber hyperlight codeact sample to 08

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

* Coerce worker exception args to strings for cross-thread safety

Stringify exc.args on the worker thread before propagating, so any
PyO3 unsendable object captured in args (e.g. via a caller-supplied
callback or underlying SDK) cannot be Dropped on the calling thread.

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

* moved sample

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
This commit is contained in:
Eduard van Valkenburg
2026-05-05 12:06:16 +02:00
committed by GitHub
Unverified
parent 36b9b41e3b
commit 57c901a245
26 changed files with 967 additions and 393 deletions
@@ -0,0 +1,31 @@
# Hyperlight CodeAct context provider
Demonstrates the provider-owned [Hyperlight](https://github.com/hyperlight-dev/hyperlight)
CodeAct flow. `HyperlightCodeActProvider` injects an `execute_code` tool into the
agent and keeps the registered sandbox tools (`compute`, `fetch_data`) hidden
from the model — the model must call them from inside the sandbox using
`call_tool(...)`.
## Installation
```bash
pip install agent-framework agent-framework-hyperlight --pre
```
> The Hyperlight Wasm backend is currently published only for `linux/x86_64` and
> `win32/AMD64` with Python `<3.14`. On other platforms `execute_code` will fail
> at runtime when it tries to create the sandbox.
## Prerequisites
- An Azure AI Foundry project endpoint (`FOUNDRY_PROJECT_ENDPOINT`)
- A deployed model (`FOUNDRY_MODEL`)
- Azure CLI authenticated (`az login`)
## Run
```bash
python code_act.py
```
See [`code_act.py`](code_act.py) for the full annotated example.
@@ -0,0 +1,187 @@
# Copyright (c) Microsoft. All rights reserved.
from __future__ import annotations
import asyncio
import logging
import os
from collections.abc import Awaitable, Callable
from typing import Annotated, Any, Literal
from agent_framework import Agent, FunctionInvocationContext, function_middleware, tool
from agent_framework.foundry import FoundryChatClient
from agent_framework.hyperlight import HyperlightCodeActProvider
from azure.identity import AzureCliCredential
from dotenv import load_dotenv
"""This sample demonstrates the provider-owned Hyperlight CodeAct flow.
The sample keeps `compute` and `fetch_data` off the direct agent tool surface and
registers them only with `HyperlightCodeActProvider`. The model therefore sees a
single `execute_code` tool and must call the provider-owned tools from inside
the sandbox with `call_tool(...)`.
"""
load_dotenv()
_CYAN = "\033[36m"
_YELLOW = "\033[33m"
_GREEN = "\033[32m"
_DIM = "\033[2m"
_RESET = "\033[0m"
class _ColoredFormatter(logging.Formatter):
"""Dim logger output so it does not compete with sample prints."""
def format(self, record: logging.LogRecord) -> str:
return f"{_DIM}{super().format(record)}{_RESET}"
logging.basicConfig(level=logging.WARNING)
logging.getLogger().handlers[0].setFormatter(
_ColoredFormatter("[%(asctime)s] %(levelname)s: %(message)s"),
)
@function_middleware
async def log_function_calls(
context: FunctionInvocationContext,
call_next: Callable[[], Awaitable[None]],
) -> None:
"""Log tool calls, including readable execute_code blocks."""
import time
function_name = context.function.name
arguments = context.arguments if isinstance(context.arguments, dict) else {}
if function_name == "execute_code" and "code" in arguments:
print(f"\n{_YELLOW}{'' * 60}")
print("▶ execute_code")
print(f"{'' * 60}{_RESET}")
print(arguments["code"])
print(f"{_YELLOW}{'' * 60}{_RESET}")
else:
pairs = ", ".join(f"{name}={value!r}" for name, value in arguments.items())
print(f"\n{_YELLOW}{function_name}({pairs}){_RESET}")
start = time.perf_counter()
await call_next()
elapsed = time.perf_counter() - start
result = context.result
if function_name == "execute_code" and isinstance(result, list):
for output in result:
if output.type == "text" and output.text:
print(f"{_GREEN}stdout:\n{output.text}{_RESET}")
elif output.type == "error" and output.error_details:
print(f"{_YELLOW}stderr:\n{output.error_details}{_RESET}")
else:
print(f"{_YELLOW}{function_name}{result!r}{_RESET}")
print(f"{_DIM} ({elapsed:.4f}s){_RESET}")
@tool(approval_mode="never_require")
def compute(
operation: Annotated[
Literal["add", "subtract", "multiply", "divide"],
"Math operation: add, subtract, multiply, or divide.",
],
a: Annotated[float, "First numeric operand."],
b: Annotated[float, "Second numeric operand."],
) -> float:
"""Perform a math operation for sandboxed code."""
operations = {
"add": a + b,
"subtract": a - b,
"multiply": a * b,
"divide": a / b if b else float("inf"),
}
return operations[operation]
@tool(approval_mode="never_require")
async def fetch_data(
table: Annotated[str, "Name of the simulated table to query."],
) -> list[dict[str, Any]]:
"""Fetch records from a named table."""
await asyncio.sleep(0.5)
data: dict[str, list[dict[str, Any]]] = {
"users": [
{"id": 1, "name": "Alice", "role": "admin"},
{"id": 2, "name": "Bob", "role": "user"},
{"id": 3, "name": "Charlie", "role": "admin"},
],
"products": [
{"id": 101, "name": "Widget", "price": 9.99},
{"id": 102, "name": "Gadget", "price": 19.99},
],
}
return data.get(table, [])
async def main() -> None:
"""Run the provider-owned Hyperlight CodeAct sample."""
# 1. Create the Hyperlight-backed provider and register sandbox tools on it.
codeact = HyperlightCodeActProvider(
tools=[compute, fetch_data],
approval_mode="never_require",
)
# 2. Create the client and the agent.
agent = Agent(
client=FoundryChatClient(
project_endpoint=os.environ["FOUNDRY_PROJECT_ENDPOINT"],
model=os.environ["FOUNDRY_MODEL"],
credential=AzureCliCredential(),
),
name="HyperlightCodeActProviderAgent",
instructions="You are a helpful assistant.",
context_providers=[codeact],
middleware=[log_function_calls],
)
# 3. Run a request that should use execute_code plus provider-owned tools.
query = (
"Fetch all users, find admins, multiply 7*(3*2), and print the users, "
"admins, and multiplication result. Use execute_code and call_tool(...) "
"inside the sandbox."
)
print(f"{_CYAN}{'=' * 60}")
print("Hyperlight CodeAct provider sample")
print(f"{'=' * 60}{_RESET}")
print(f"{_CYAN}User: {query}{_RESET}")
result = await agent.run(query)
print(f"{_CYAN}Agent: {result.text}{_RESET}")
"""
Sample output (shape only):
============================================================
Hyperlight CodeAct provider sample
============================================================
User: Fetch all users, find admins, multiply 7*(3*2), ...
────────────────────────────────────────────────────────────
▶ execute_code
────────────────────────────────────────────────────────────
users = call_tool("fetch_data", table="users")
admins = [user for user in users if user["role"] == "admin"]
result = call_tool("compute", operation="multiply", a=7, b=6)
print("Users:", users)
print("Admins:", admins)
print("7 * 6 =", result)
────────────────────────────────────────────────────────────
stdout:
Users: [...]
Admins: [...]
7 * 6 = 42.0
(0.0xxx s)
Agent: ...
"""
if __name__ == "__main__":
asyncio.run(main())
@@ -0,0 +1,37 @@
# Hyperlight local code interpreter
Demonstrates the standalone [Hyperlight](https://github.com/hyperlight-dev/hyperlight)
`HyperlightExecuteCodeTool` — a sandboxed local code interpreter that the agent
can invoke directly. Two patterns are shown:
| File | Pattern |
|------|---------|
| [`local_code_interpreter.py`](local_code_interpreter.py) | **Standalone tool**`HyperlightExecuteCodeTool` is added to the agent tool list and self-describes its sandbox tools, so no extra agent instructions are needed. Best for quick prototyping. |
| [`local_code_interpreter_manual_wiring.py`](local_code_interpreter_manual_wiring.py) | **Manual static wiring** — sandbox tools and CodeAct instructions are built once and passed to the `Agent` constructor alongside a direct-only tool (`send_email`). Best when the tool set is fixed for the agent's lifetime. |
For the recommended provider-driven pattern (with dynamic tool / capability
management), see
[`../../context_providers/code_act/`](../../context_providers/code_act/).
## Installation
```bash
pip install agent-framework agent-framework-hyperlight --pre
```
> The Hyperlight Wasm backend is currently published only for `linux/x86_64` and
> `win32/AMD64` with Python `<3.14`. On other platforms `execute_code` will fail
> at runtime when it tries to create the sandbox.
## Prerequisites
- An Azure AI Foundry project endpoint (`FOUNDRY_PROJECT_ENDPOINT`)
- A deployed model (`FOUNDRY_MODEL`)
- Azure CLI authenticated (`az login`)
## Run
```bash
python local_code_interpreter.py
python local_code_interpreter_manual_wiring.py
```
@@ -0,0 +1,109 @@
# Copyright (c) Microsoft. All rights reserved.
from __future__ import annotations
import asyncio
import os
from typing import Annotated, Any, Literal
from agent_framework import Agent, tool
from agent_framework.foundry import FoundryChatClient
from agent_framework.hyperlight import HyperlightExecuteCodeTool
from azure.identity import AzureCliCredential
from dotenv import load_dotenv
"""This sample demonstrates the standalone Hyperlight execute_code tool.
The sample adds `HyperlightExecuteCodeTool` directly to the agent. The tool's
own description advertises `call_tool(...)`, the registered sandbox tools, and
the current capability configuration, so no extra CodeAct-specific agent
instructions are required.
"""
load_dotenv()
@tool(approval_mode="never_require")
def compute(
operation: Annotated[
Literal["add", "subtract", "multiply", "divide"],
"Math operation: add, subtract, multiply, or divide.",
],
a: Annotated[float, "First numeric operand."],
b: Annotated[float, "Second numeric operand."],
) -> float:
"""Perform a math operation used by sandboxed code."""
operations = {
"add": a + b,
"subtract": a - b,
"multiply": a * b,
"divide": a / b if b else float("inf"),
}
return operations[operation]
@tool(approval_mode="never_require")
def fetch_data(
table: Annotated[str, "Name of the simulated table to query."],
) -> list[dict[str, Any]]:
"""Fetch simulated records from a named table."""
data: dict[str, list[dict[str, Any]]] = {
"users": [
{"id": 1, "name": "Alice", "role": "admin"},
{"id": 2, "name": "Bob", "role": "user"},
{"id": 3, "name": "Charlie", "role": "admin"},
],
"products": [
{"id": 101, "name": "Widget", "price": 9.99},
{"id": 102, "name": "Gadget", "price": 19.99},
],
}
return data.get(table, [])
async def main() -> None:
"""Run the standalone execute_code sample."""
# 1. Create the packaged execute_code tool and register sandbox tools on it.
execute_code = HyperlightExecuteCodeTool(
tools=[compute, fetch_data],
approval_mode="never_require",
)
# 2. Create the client and the agent.
agent = Agent(
client=FoundryChatClient(
project_endpoint=os.environ["FOUNDRY_PROJECT_ENDPOINT"],
model=os.environ["FOUNDRY_MODEL"],
credential=AzureCliCredential(),
),
name="HyperlightExecuteCodeToolAgent",
instructions="You are a helpful assistant.",
tools=execute_code,
)
# 3. Run one request through the direct-tool surface.
print("=" * 60)
print("Hyperlight execute_code tool sample")
print("=" * 60)
query = (
"Fetch all users, find admins, multiply 6*7, and print the users, admins, "
"and multiplication result. Use one execute_code call."
)
print(f"User: {query}")
result = await agent.run(query)
print(f"Agent: {result.text}")
"""
Sample output (shape only):
============================================================
Hyperlight execute_code tool sample
============================================================
User: Fetch all users, find admins, multiply 6*7, ...
Agent: ...
"""
if __name__ == "__main__":
asyncio.run(main())
@@ -0,0 +1,132 @@
# Copyright (c) Microsoft. All rights reserved.
from __future__ import annotations
import asyncio
import os
from typing import Annotated, Any, Literal
from agent_framework import Agent, tool
from agent_framework.foundry import FoundryChatClient
from agent_framework.hyperlight import HyperlightExecuteCodeTool
from azure.identity import AzureCliCredential
from dotenv import load_dotenv
"""This sample demonstrates manual static wiring of CodeAct without a provider.
Instead of using `HyperlightCodeActProvider` with `context_providers=`, this
sample creates a `HyperlightExecuteCodeTool` directly, extracts its CodeAct
instructions once, and passes both to the `Agent` constructor at build time.
This avoids the per-run provider lifecycle (`before_run` / `after_run`) and is
well-suited when the tool registry, file mounts, and network allow-list are
fixed for the agent's lifetime. The tradeoff is that dynamic tool or capability
changes between runs are not supported — any mutations to the tool would not
update the agent's instructions automatically.
"""
load_dotenv()
@tool(approval_mode="never_require")
def compute(
operation: Annotated[
Literal["add", "subtract", "multiply", "divide"],
"Math operation: add, subtract, multiply, or divide.",
],
a: Annotated[float, "First numeric operand."],
b: Annotated[float, "Second numeric operand."],
) -> float:
"""Perform a math operation used by sandboxed code."""
operations = {
"add": a + b,
"subtract": a - b,
"multiply": a * b,
"divide": a / b if b else float("inf"),
}
return operations[operation]
@tool(approval_mode="never_require")
def fetch_data(
table: Annotated[str, "Name of the simulated table to query."],
) -> list[dict[str, Any]]:
"""Fetch simulated records from a named table."""
data: dict[str, list[dict[str, Any]]] = {
"users": [
{"id": 1, "name": "Alice", "role": "admin"},
{"id": 2, "name": "Bob", "role": "user"},
{"id": 3, "name": "Charlie", "role": "admin"},
],
"products": [
{"id": 101, "name": "Widget", "price": 9.99},
{"id": 102, "name": "Gadget", "price": 19.99},
],
}
return data.get(table, [])
@tool(approval_mode="never_require")
def send_email(
to: Annotated[str, "Recipient email address."],
subject: Annotated[str, "Email subject line."],
body: Annotated[str, "Email body text."],
) -> str:
"""Simulate sending an email (direct-only tool, not available inside the sandbox)."""
return f"Email sent to {to}: {subject}"
async def main() -> None:
"""Run the manual static-wiring sample."""
# 1. Create the execute_code tool and register sandbox tools on it.
execute_code = HyperlightExecuteCodeTool(
tools=[compute, fetch_data],
approval_mode="never_require",
)
# 2. Build CodeAct instructions once. Setting tools_visible_to_model=False
# tells the instructions builder that sandbox tools are not in the agent's
# direct tool list, so the model must use call_tool(...) inside execute_code.
codeact_instructions = execute_code.build_instructions(tools_visible_to_model=False)
# 3. Create the client and the agent with everything wired at construction time.
# - send_email is a direct-only tool (not available inside the sandbox).
# - execute_code carries sandbox tools (compute, fetch_data) via call_tool.
agent = Agent(
client=FoundryChatClient(
project_endpoint=os.environ["FOUNDRY_PROJECT_ENDPOINT"],
model=os.environ["FOUNDRY_MODEL"],
credential=AzureCliCredential(),
),
name="ManualWiringAgent",
instructions=f"You are a helpful assistant.\n\n{codeact_instructions}",
tools=[send_email, execute_code],
)
# 4. Run a request that exercises both the sandbox and the direct tool.
print("=" * 60)
print("Manual static-wiring CodeAct sample")
print("=" * 60)
query = (
"Fetch all users, find admins, multiply 6*7, and print the users, admins, "
"and multiplication result. Use one execute_code call. "
"Then send an email to admin@example.com summarising the results."
)
print(f"User: {query}")
result = await agent.run(query)
print(f"Agent: {result.text}")
"""
Sample output (shape only):
============================================================
Manual static-wiring CodeAct sample
============================================================
User: Fetch all users, find admins, multiply 6*7, ...
Agent: ...
"""
if __name__ == "__main__":
asyncio.run(main())