ecp-sdk 0.4.0

Python SDK for portable AI agent evaluations with outputs, tool calls, and audit context.

ECP Python SDK

Python SDK for building agents that comply with the Evaluation Context Protocol (ECP).

ECP is a vendor-neutral protocol for testing agent outputs, tool calls, and evaluator-visible audit context across frameworks, models, eval platforms, and CI systems.

Install

pip install "ecp-sdk==0.3.1"

Framework extras:

pip install "ecp-sdk[langchain]==0.3.1"
pip install "ecp-sdk[crewai]==0.3.1"
pip install "ecp-sdk[llamaindex]==0.3.1"
pip install "ecp-sdk[pydanticai]==0.3.1"

Usage

from ecp import Result, agent, on_step, serve


@agent(name="MyAgent")
class MyAgent:
    @on_step
    def step(self, user_input: str):
        return Result(
            public_output=f"Echo: {user_input}",
            evaluation_context="Echoed the input for evaluation.",
            tool_calls=[{"name": "echo", "arguments": {"text": user_input}}],
        )


if __name__ == "__main__":
    serve(MyAgent())

evaluation_context is the preferred field for evaluator-safe audit evidence. private_thought is still accepted as a deprecated compatibility alias.

Async lifecycle hooks

@on_step and @on_reset may be synchronous functions or async def coroutines. The SDK awaits async hooks on one persistent event loop, so loop-bound clients and other async resources can be reused across requests.

import asyncio

from ecp import Result, agent, on_reset, on_step, serve


@agent(name="AsyncAgent")
class AsyncAgent:
    @on_step
    async def step(self, user_input: str) -> Result:
        await asyncio.sleep(0.01)
        return Result(public_output=f"Processed: {user_input}")

    @on_reset
    async def reset(self) -> None:
        await asyncio.sleep(0)


if __name__ == "__main__":
    serve(AsyncAgent())

The same hooks work with serve_http(...). See examples/async_python_demo for a runnable agent that supports either transport.

Streamable HTTP

Agents can also run as an ECP Streamable HTTP server:

if __name__ == "__main__":
    ecp.serve_http(MyAgent(), host="127.0.0.1", port=8765, path="/ecp")

The endpoint accepts JSON-RPC POST requests at /ecp. It returns JSON for requests, 202 Accepted for notifications, and 405 Method Not Allowed for GET SSE streams until ECP defines server-initiated messages.

Links

• Documentation: https://evaluationcontextprotocol.io/
• Repository: https://github.com/evaluation-context-protocol/ecp
• Issues: https://github.com/evaluation-context-protocol/ecp/issues