Files
Evan Mattson 4aa737eee5 Python: [BREAKING] Require building functional workflow instances (#7521)
* Harden functional workflow continuation authority

Use a versioned opaque single-use token on WorkflowRunResult, validate it before request correlation, consume it immediately before replayed user code, and rotate it on each pause. Carry the same explicit authority through streaming and non-streaming FunctionalWorkflowAgent responses.

Files changed: functional workflow/runtime result APIs, functional HITL regression tests, core agent guidance, and the functional HITL sample.

Next iteration: enforce pending-state overlap and token-authorized abandonment, then document and test checkpoint authorization boundaries.

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

* Enforce one pending functional continuation

Reject fresh messages and checkpoint restores while an in-memory continuation is pending. Add token-authorized abandonment on FunctionalWorkflow and FunctionalWorkflowAgent, and clear retained replay state atomically when authority is consumed while preserving the active message for token rotation and checkpoints.

Files changed: functional workflow runtime and agent adapter, functional lifecycle regression tests, and core workflow guidance.

Next iteration: preserve and document authorized checkpoint continuation boundaries.

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

* Preserve authorized functional checkpoint continuation

Treat checkpoint restore as a host- and storage-authorized path independent of process-local continuation tokens, and issue fresh authority whenever restored execution pauses again. Cover default and per-run storage, deterministic and custom request IDs, token rotation, and checkpoint-plus-response restore.

Files changed: functional workflow and checkpoint interface guidance, functional checkpoint lifecycle tests, the functional HITL sample, and core workflow guidance.

Next iteration: run the final repository-wide Python validation gates.

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

* Validate Python continuation hardening

Run the complete Python workspace checks, aggregate coverage suite, repository hooks, and core package build from the final combined worktree. Keep the validation iteration code-neutral because all gates pass without corrective changes.

Files changed: none; this commit records the final validation gate.

Blockers: none. Next iteration: no remaining AFK tasks.

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

* Handle functional checkpoint continuation failures

Publish retained continuation state only after checkpoint persistence succeeds, and cover reuse after a transient save failure.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

* Address functional continuation review findings

Add owner recovery for lost tokens, harden malformed token validation, preserve consistent failure surfaces, and keep agent pending state aligned with resumable workflow state.

Document process-local single-use continuation semantics and extend regression coverage across direct, streaming, checkpoint, and agent paths.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

* Handle functional continuation cancellation

Release the workflow run guard when cancellation interrupts resumed user code while keeping the single-use continuation token consumed.

Replace sample assertions with explicit runtime checks and add cancellation regression coverage.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

* Simplify functional workflow instance isolation

Remove continuation-token handling and align functional workflows with the graph workflow ownership model: one stateful instance per logical caller or session.

Add create_instance() for independent callers, document the ownership contract, and cover pending-state isolation between instances.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

* Scope functional workflow checkpoint storage

Do not inherit checkpoint storage when creating an independent workflow instance. Allow hosts to provide an explicitly caller-scoped storage adapter and document that shared checkpoint access requires host authorization and tenant isolation.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

* Require building functional workflow instances

Make @workflow return a stateless FunctionalWorkflowDefinition and require build() before run() or as_agent(). This aligns functional workflows with the graph definition/build lifecycle and prevents module-level decorated definitions from retaining caller state.

Move checkpoint configuration to build(), export the definition type, migrate samples, and cover isolated built instances.

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

Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78

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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: a8f47743-1cdc-4924-8e1b-667d0d790b78
2026-08-14 00:31:52 +00:00

111 lines
3.7 KiB
Python

# Copyright (c) Microsoft. All rights reserved.
"""Calling agents inside functional workflows.
Agent calls work inside @workflow as plain function calls — no decorator needed.
Just call the agent and use the result.
If you want per-step caching (so agent calls don't re-execute on HITL resume
or crash recovery), add @step. Since each agent call hits an LLM API (time +
money), @step is often worth it. But it's always opt-in.
This sample shows both approaches side-by-side so you can see the difference.
"""
import asyncio
from agent_framework import Agent, step, workflow
from agent_framework.foundry import FoundryChatClient
from azure.identity import AzureCliCredential
# ---------------------------------------------------------------------------
# Create agents
# ---------------------------------------------------------------------------
client = FoundryChatClient(credential=AzureCliCredential())
classifier_agent = Agent(
name="ClassifierAgent",
instructions=(
"Classify documents into one category: Technical, Legal, Marketing, or Scientific. "
"Reply with only the category name."
),
client=client,
)
writer_agent = Agent(
name="WriterAgent",
instructions="Summarize the given content in one sentence.",
client=client,
)
reviewer_agent = Agent(
name="ReviewerAgent",
instructions="Review the given summary in one sentence. Is it accurate and complete?",
client=client,
)
# ---------------------------------------------------------------------------
# Simplest approach: call agents directly inside the workflow.
# No @step, no wrappers — just plain function calls.
# ---------------------------------------------------------------------------
@workflow
async def simple_pipeline(document: str) -> str:
"""Process a document — agents called inline, no @step."""
classification = (await classifier_agent.run(f"Classify this document: {document}")).text
summary = (await writer_agent.run(f"Summarize: {document}")).text
review = (await reviewer_agent.run(f"Review this summary: {summary}")).text
return f"Classification: {classification}\nSummary: {summary}\nReview: {review}"
# ---------------------------------------------------------------------------
# With @step: agent results are cached. On HITL resume or checkpoint
# recovery, completed steps return their saved result instead of calling
# the LLM again. Worth it for expensive operations.
# ---------------------------------------------------------------------------
@step
async def classify_document(doc: str) -> str:
return (await classifier_agent.run(f"Classify this document: {doc}")).text
@step
async def generate_summary(doc: str) -> str:
return (await writer_agent.run(f"Summarize: {doc}")).text
@step
async def review_summary(summary: str) -> str:
return (await reviewer_agent.run(f"Review this summary: {summary}")).text
@workflow
async def cached_pipeline(document: str) -> str:
"""Same pipeline, but @step caches each agent call."""
classification = await classify_document(document)
summary = await generate_summary(document)
review = await review_summary(summary)
return f"Classification: {classification}\nSummary: {summary}\nReview: {review}"
async def main():
simple_workflow = simple_pipeline.build()
cached_workflow = cached_pipeline.build()
# Simple version — agents called inline
result = await simple_workflow.run("This is a technical document about machine learning...")
print(result.get_outputs()[0])
# Cached version — same result, but steps won't re-execute on resume
result = await cached_workflow.run("This is a technical document about machine learning...")
print(f"\nCached: {result.get_outputs()[0]}")
if __name__ == "__main__":
asyncio.run(main())