Usage - Phaseo Docs

Prepare the runtime

The independent package is not yet on PyPI. Follow the source installation instructions.

Quickstart

from phaseo_agent import create_agent, create_gateway_agent_client

agent = create_agent({
    "id": "quickstart-agent",
    "model": "openai/gpt-5.4-nano",
    "instructions": "Answer concisely and helpfully.",
})

result = agent.run(
    input="Give me one fun fact about cURL.",
    client=create_gateway_agent_client(),
)

print(result.output)

What it ships

create_agent(...)
define_tool(...)
create_gateway_agent_client(...)
retries, concurrent tools, timeouts, and lifecycle events
human-review pauses with continue_run(...)
serializable state and Phaseo Devtools capture

Advanced runtime

Python supports callable schemas and approvals, HITL and manual tools, progress, recoverable errors, replayable streams, stop helpers, dynamic turns, persisted next-turn overrides, normalized usage/cost, and application-owned state accessors.

Streaming and cancellation

agent.stream(...) and agent.continue_stream(...) use the gateway’s Responses SSE stream. Consume text_stream(), reasoning_stream(), item_stream(), tool_stream(), or full_stream(); call cancel() to close the active request. Completed steps retain request IDs, provider metadata, finish reasons, warnings, usage, and cost.

Last modified on July 26, 2026