qerexa (Python, preview)

Python clients for Qerexa:

• QerexaGateMiddleware puts a Qerexa check in front of any Python function: AutoGen functions, CrewAI or LangChain tools, or your own code.
• QerexaVCClient issues and verifies credentials, federation tokens and trust relationships between organizations.

Install

pip install qerexa

Gate a function

import os
from qerexa import (
    ExecutionAuthorizationRequiredError,
    GateBlockedError,
    QerexaGateMiddleware,
)

gate = QerexaGateMiddleware(api_key=os.environ["QEREXA_API_KEY"])

@gate.gate_check(action="report.export", reasoning="Monthly compliance export")
def export_report(report_id: str) -> str:
    ...

try:
    export_report("rpt_123")
except ExecutionAuthorizationRequiredError as e:
    # Human review was requested (flow e.flow_id). Approval of that review does
    # not authorize this call; stop here or use an action-bound execution flow.
    ...
except GateBlockedError as e:
    ...

Your function runs only when Qerexa gives a clear, current yes: an allowed decision with its own ID and an expiry still in the future. Anything else raises before your code starts, whether that's a block, a pending review, an expired or garbled answer, a redirect, or a network failure. Every one of those errors derives from QerexaError.

Your function's arguments never leave your process. Qerexa sees the action, the actor, the reasoning you pass (the function name by default) and any metadata, so keep credentials and customer data out of those.

With CrewAI, decorate the function behind the tool before handing it over. The check then runs on every call, whatever CrewAI's callbacks do.

Verifiable credentials

from qerexa import VCClientConfig, create_vc_client

vc = create_vc_client(VCClientConfig(org_id="org_123", api_key=os.environ["QEREXA_API_KEY"]))
relationships = vc.list_trust_relationships(limit=10)

Requests time out after 10 seconds by default (VCClientConfig(timeout=...)).

Preview limits

This is a preview, not a certified execution control. It doesn't verify receipts, wait on review flows, or tie an approval to one specific execution, so keep payments, deployments and other high-impact actions behind the documented API proof flow and an execution contract you've reviewed independently.

Development

python -m pip install -e "./packages/sdk-python[dev]"
ruff check packages/sdk-python
pytest packages/sdk-python

Releases follow the SDK release runbook.