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Python SDK for Conductor

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Python SDK for Conductor (OSS and Orkes Conductor) — an orchestration platform for building distributed applications, AI agents, and workflow-driven microservices. Define workflows as code, run workers anywhere, and let Conductor handle retries, state management, and observability.

If you find Conductor useful, please consider giving it a star on GitHub -- it helps the project grow.

GitHub stars

Start Conductor server

If you don't already have a Conductor server running, pick one:

Docker Compose (recommended, includes UI):

docker run -p 8080:8080 conductoross/conductor:latest

The UI will be available at http://localhost:8080 and the API at http://localhost:8080/api

MacOS / Linux (one-liner): (If you don't want to use docker, you can install and run the binary directly)

curl -sSL https://raw.githubusercontent.com/conductor-oss/conductor/main/conductor_server.sh | sh

Conductor CLI

# Installs conductor cli
npm install -g @conductor-oss/conductor-cli

# Start the open source conductor server
conductor server start
# see conductor server --help for all the available commands

Install the SDK

pip install conductor-python

60-Second Quickstart

Step 1: Create a workflow

Workflows are definitions that reference task types (e.g. a SIMPLE task called greet). We'll build a workflow called greetings that runs one task and returns its output.

Assuming you have a WorkflowExecutor (executor) and a worker task (greet):

from conductor.client.workflow.conductor_workflow import ConductorWorkflow

workflow = ConductorWorkflow(name='greetings', version=1, executor=executor)
greet_task = greet(task_ref_name='greet_ref', name=workflow.input('name'))
workflow >> greet_task
workflow.output_parameters({'result': greet_task.output('result')})
workflow.register(overwrite=True)

Step 2: Write worker

Workers are just Python functions decorated with @worker_task that poll Conductor for tasks and execute them.

from conductor.client.worker.worker_task import worker_task

# register_task_def=True is convenient for local dev quickstarts; in production, manage task definitions separately.
@worker_task(task_definition_name='greet', register_task_def=True)
def greet(name: str) -> str:
    return f'Hello {name}'

Step 3: Run your first workflow app

Create a quickstart.py with the following:

from conductor.client.automator.task_handler import TaskHandler
from conductor.client.configuration.configuration import Configuration
from conductor.client.orkes_clients import OrkesClients
from conductor.client.workflow.conductor_workflow import ConductorWorkflow
from conductor.client.worker.worker_task import worker_task


# A worker is any Python function.
@worker_task(task_definition_name='greet', register_task_def=True)
def greet(name: str) -> str:
    return f'Hello {name}'


def main():
    # Configure the SDK (reads CONDUCTOR_SERVER_URL / CONDUCTOR_AUTH_* from env).
    config = Configuration()

    clients = OrkesClients(configuration=config)
    executor = clients.get_workflow_executor()

    # Build a workflow with the >> operator.
    workflow = ConductorWorkflow(name='greetings', version=1, executor=executor)
    greet_task = greet(task_ref_name='greet_ref', name=workflow.input('name'))
    workflow >> greet_task
    workflow.output_parameters({'result': greet_task.output('result')})
    workflow.register(overwrite=True)

    # Start polling for tasks (one worker subprocess per worker function).
    with TaskHandler(configuration=config, scan_for_annotated_workers=True) as task_handler:
        task_handler.start_processes()

        # Run the workflow and get the result.
        run = executor.execute(name='greetings', version=1, workflow_input={'name': 'Conductor'})
        print(f'result: {run.output["result"]}')
        print(f'execution: {config.ui_host}/execution/{run.workflow_id}')


if __name__ == '__main__':
    main()

Run it:

python quickstart.py

Using Orkes Conductor / Remote Server?

Export your authentication credentials as well:

export CONDUCTOR_SERVER_URL="https://your-cluster.orkesconductor.io/api"

# If using Orkes Conductor that requires auth key/secret
export CONDUCTOR_AUTH_KEY="your-key"
export CONDUCTOR_AUTH_SECRET="your-secret"

# Optional — set to false to force HTTP/1.1 if your network environment has unstable long-lived HTTP/2 connections (default: true)
# export CONDUCTOR_HTTP2_ENABLED=false

See Configuration for details.

That's it -- you just defined a worker, built a workflow, and executed it. Open the Conductor UI (default: http://localhost:8127) to see the execution.

Comprehensive worker example

The example includes sync + async workers, metrics, and long-running tasks

See examples/workers_e2e.py


Workers

Workers are Python functions that execute Conductor tasks. Decorate any function with @worker_task to:

  • register it as a worker (auto-discovered by TaskHandler)
  • use it as a workflow task (call it with task_ref_name=...)

Note: Workers can also be used by LLMs for tool calling (see AI & LLM Workflows).

from conductor.client.worker.worker_task import worker_task

@worker_task(task_definition_name='greet')
def greet(name: str) -> str:
    return f'Hello {name}'

Async workers for I/O-bound tasks — the SDK automatically uses AsyncTaskRunner (event loop, no thread overhead):

import httpx

@worker_task(task_definition_name='fetch_data')
async def fetch_data(url: str) -> dict:
    async with httpx.AsyncClient() as client:
        response = await client.get(url)
    return response.json()

Start workers with TaskHandler:

Note: @worker_task functions are discovered only after their modules are imported. Either import your worker modules explicitly, or pass import_modules=[...] when constructing TaskHandler.

from conductor.client.automator.task_handler import TaskHandler
from conductor.client.configuration.configuration import Configuration

api_config = Configuration()
task_handler = TaskHandler(
    workers=[],
    configuration=api_config,
    scan_for_annotated_workers=True,  # auto-discover @worker_task functions
    # monitor_processes=True and restart_on_failure=True by default
)
task_handler.start_processes()
try:
    task_handler.join_processes()  # blocks (workers poll forever)
finally:
    task_handler.stop_processes()

Workers support complex inputs (dataclasses), long-running tasks (TaskInProgress), and hierarchical configuration via environment variables.

Resilience: auto-restart and health checks

Workers are typically long-lived services. By default, TaskHandler monitors worker subprocesses and restarts them if they exit unexpectedly.

For a /healthcheck endpoint, you can use:

task_handler.is_healthy()
task_handler.get_worker_process_status()

To disable monitoring/restarts (e.g., local debugging):

TaskHandler(..., monitor_processes=False, restart_on_failure=False)

Worker Configuration

Workers support hierarchical environment variable configuration — global settings that can be overridden per worker:

# Global (all workers)
export CONDUCTOR_WORKER_ALL_POLL_INTERVAL_MILLIS=250
export CONDUCTOR_WORKER_ALL_THREAD_COUNT=20
export CONDUCTOR_WORKER_ALL_DOMAIN=production

# Per-worker override
export CONDUCTOR_WORKER_GREETINGS_THREAD_COUNT=50

See WORKER_CONFIGURATION.md for all options.

Monitoring Workers

Enable Prometheus metrics:

from conductor.client.automator.task_handler import TaskHandler
from conductor.client.configuration.configuration import Configuration
from conductor.client.configuration.settings.metrics_settings import MetricsSettings

api_config = Configuration()
metrics_settings = MetricsSettings(directory='/tmp/conductor-metrics', http_port=8000)

task_handler = TaskHandler(configuration=api_config, metrics_settings=metrics_settings, scan_for_annotated_workers=True)
task_handler.start_processes()
# Metrics at http://localhost:8000/metrics
try:
    task_handler.join_processes()  # blocks (workers poll forever)
finally:
    task_handler.stop_processes()

See METRICS.md for details.

Learn more:

Workflows

Define workflows in Python using the >> operator to chain tasks:

from conductor.client.configuration.configuration import Configuration
from conductor.client.orkes_clients import OrkesClients
from conductor.client.workflow.conductor_workflow import ConductorWorkflow

api_config = Configuration()
clients = OrkesClients(configuration=api_config)
workflow_executor = clients.get_workflow_executor()

workflow = ConductorWorkflow(name='greetings', version=1, executor=workflow_executor)
# Assuming greet is defined (see Workers section above).
workflow >> greet(task_ref_name='greet_ref', name=workflow.input('name'))
# Registering is required if you want to start/execute by name+version; optional if you only execute inline.
workflow.register(overwrite=True)

Execute workflows:

# Synchronous (waits for completion)
result = workflow_executor.execute(name='greetings', version=1, workflow_input={'name': 'Orkes'})
print(result.output)

# Asynchronous (returns workflow ID immediately)
from conductor.client.http.models import StartWorkflowRequest
request = StartWorkflowRequest(name='greetings', version=1, input={'name': 'Orkes'})
workflow_id = workflow_executor.start_workflow(request)

# Inline (sends the workflow definition with the request; no prior register required)
run = workflow.execute(workflow_input={'name': 'Orkes'}, wait_for_seconds=10)
print(run.output)

Manage running workflows and send signals:

from conductor.client.orkes_clients import OrkesClients

clients = OrkesClients(configuration=api_config)
workflow_client = clients.get_workflow_client()

workflow_client.pause_workflow(workflow_id)
workflow_client.resume_workflow(workflow_id)
workflow_client.terminate_workflow(workflow_id, reason='no longer needed')
workflow_client.retry_workflow(workflow_id)
workflow_client.restart_workflow(workflow_id)

Learn more:

Troubleshooting

  • Worker stops polling or crashes: TaskHandler monitors and restarts worker subprocesses by default. Consider exposing a /healthcheck endpoint using task_handler.is_healthy() + task_handler.get_worker_process_status(). If you enable metrics, alert on worker_restart_total.
  • httpcore.RemoteProtocolError: <ConnectionTerminated ...>: the SDK recreates the underlying HTTP client and retries once for idempotent requests. If your environment is still unstable with HTTP/2, set CONDUCTOR_HTTP2_ENABLED=false (forces HTTP/1.1) — see docs/WORKER.md.
  • FastAPI/Uvicorn: avoid running uvicorn with multiple web workers unless you explicitly want multiple independent TaskHandlers polling Conductor (see examples/fastapi_worker_service.py).

AI & LLM Workflows

Conductor supports AI-native workflows including agentic tool calling, RAG pipelines, and multi-agent orchestration.

Agentic Workflows

Build AI agents where LLMs dynamically select and call Python workers as tools. See examples/agentic_workflows/ for all examples.

Example Description
llm_chat.py Automated multi-turn science Q&A between two LLMs
llm_chat_human_in_loop.py Interactive chat with WAIT task pauses for user input
multiagent_chat.py Multi-agent debate with moderator routing between panelists
function_calling_example.py LLM picks which Python function to call based on user queries
mcp_weather_agent.py AI agent using MCP tools for weather queries

LLM and RAG Workflows

Example Description
rag_workflow.py End-to-end RAG: document conversion (PDF/Word/Excel), pgvector indexing, semantic search, answer generation
vector_db_helloworld.py Vector database operations: text indexing, embedding generation, and semantic search with Pinecone
# Automated multi-turn chat
python examples/agentic_workflows/llm_chat.py

# Multi-agent debate
python examples/agentic_workflows/multiagent_chat.py --topic "renewable energy"

# RAG pipeline
pip install "markitdown[pdf]"
python examples/rag_workflow.py document.pdf "What are the key findings?"

Examples

See the Examples Guide for the full catalog. Key examples:

Example Description Run
workers_e2e.py End-to-end: sync + async workers, metrics python examples/workers_e2e.py
fastapi_worker_service.py FastAPI: expose a workflow as an API (+ workers) (deps: fastapi, uvicorn) uvicorn examples.fastapi_worker_service:app --port 8081 --workers 1
helloworld.py Minimal hello world python examples/helloworld/helloworld.py
dynamic_workflow.py Build workflows programmatically python examples/dynamic_workflow.py
llm_chat.py AI multi-turn chat python examples/agentic_workflows/llm_chat.py
rag_workflow.py RAG pipeline (PDF → pgvector → answer) python examples/rag_workflow.py file.pdf "question"
task_context_example.py Long-running tasks with TaskInProgress python examples/task_context_example.py
workflow_ops.py Pause, resume, terminate workflows python examples/workflow_ops.py
test_workflows.py Unit testing workflows python -m unittest examples.test_workflows
kitchensink.py All task types (HTTP, JS, JQ, Switch) python examples/kitchensink.py

API Journey Examples

End-to-end examples covering all APIs for each domain:

Example APIs Run
authorization_journey.py Authorization APIs python examples/authorization_journey.py
metadata_journey.py Metadata APIs python examples/metadata_journey.py
schedule_journey.py Schedule APIs python examples/schedule_journey.py
prompt_journey.py Prompt APIs python examples/prompt_journey.py

Documentation

Document Description
Worker Design Architecture: AsyncTaskRunner vs TaskRunner, discovery, lifecycle
Worker Guide All worker patterns (function, class, annotation, async)
Worker Configuration Hierarchical environment variable configuration
Workflow Management Start, pause, resume, terminate, retry, search
Workflow Testing Unit testing with mock outputs
Task Management Task operations
Metadata Task & workflow definitions
Authorization Users, groups, applications, permissions
Schedules Workflow scheduling
Secrets Secret storage
Prompts AI/LLM prompt templates
Integrations AI/LLM provider integrations
Metrics Prometheus metrics collection
Examples Complete examples catalog

Support

Frequently Asked Questions

Is this the same as Netflix Conductor?

Yes. Conductor OSS is the continuation of the original Netflix Conductor repository after Netflix contributed the project to the open-source foundation.

Is this project actively maintained?

Yes. Orkes is the primary maintainer and offers an enterprise SaaS platform for Conductor across all major cloud providers.

Can Conductor scale to handle my workload?

Conductor was built at Netflix to handle massive scale and has been battle-tested in production environments processing millions of workflows. It scales horizontally to meet virtually any demand.

Does Conductor support durable code execution?

Yes. Conductor ensures workflows complete reliably even in the face of infrastructure failures, process crashes, or network issues.

Are workflows always asynchronous?

No. While Conductor excels at asynchronous orchestration, it also supports synchronous workflow execution when immediate results are required.

Do I need to use a Conductor-specific framework?

No. Conductor is language and framework agnostic. Use your preferred language and framework -- the SDKs provide native integration for Python, Java, JavaScript, Go, C#, and more.

Can I mix workers written in different languages?

Yes. A single workflow can have workers written in Python, Java, Go, or any other supported language. Workers communicate through the Conductor server, not directly with each other.

What Python versions are supported?

Python 3.9 and above.

Should I use def or async def for my workers?

Use async def for I/O-bound tasks (API calls, database queries) -- the SDK uses AsyncTaskRunner with a single event loop for high concurrency with low overhead. Use regular def for CPU-bound or blocking work -- the SDK uses TaskRunner with a thread pool. The SDK selects the right runner automatically based on your function signature.

How do I run workers in production?

Workers are standard Python processes. Deploy them as you would any Python application -- in containers, VMs, or bare metal. Workers poll the Conductor server for tasks, so no inbound ports need to be opened. See Worker Design for architecture details.

How do I test workflows without running a full Conductor server?

The SDK provides a test framework that uses Conductor's POST /api/workflow/test endpoint to evaluate workflows with mock task outputs. See Workflow Testing for details.

License

Apache 2.0