nexus-a2a-sdk
NEXUS Python SDK: deterministic governance for agent, tool, and payment execution.
The Python SDK for NEXUS, an optional AI SAFE² reference implementation for governed agent actions.
Install
pip install nexus-a2a-sdk
# Full production stack (embeddings + OPA client + OpenTelemetry)
pip install "nexus-a2a-sdk[full]"
What's Included
| Module | What it does |
|---|---|
nexus_sdk.cael |
CAEL envelope, APEM message types, JouleWork economic accounting |
nexus_sdk.memory |
Memory Vaccine: injection detection, drift scoring, provenance |
nexus_sdk.guardian |
Guardian Integration Profile: per-call argument inspection |
nexus_sdk.otel |
NOR output receipts, OpenTelemetry/OCSF audit export |
nexus_sdk.agbom |
Dynamic Agent Bill of Materials: real-time, hash-chained |
nexus_sdk.bridges |
Protocol bridges: MCP, ACS, A2A, LangChain, CrewAI, n8n, REST |
nexus_sdk.payments |
Sovereign Payment Gateway contracts, deterministic controls, evidence, and readiness gates |
Quick Example
from nexus_sdk.guardian import GuardianPolicy, NEXUSGuardianClient, build_tool_call_step
policy = GuardianPolicy(blocked_argument_patterns=["../"])
guardian = NEXUSGuardianClient(inline_policy=policy,
fail_mode=NEXUSGuardianClient.FAIL_CLOSED)
step = build_tool_call_step(
agent_did="did:nexus:agent:my-agent",
spiffe_id="spiffe://nexus.local/agent/my-agent",
tool_name="read_file",
tool_arguments={"path": "../../etc/passwd"},
act_tier=2,
)
verdict = guardian.evaluate(step)
print(verdict.decision) # deny
Documentation
Full documentation, reference deployment, OPA policies, JSON schemas, and the IETF draft: github.com/CyberStrategyInstitute/ai-safe2-framework/NEXUS
License
Apache 2.0. See LICENSE.
1 maintainer
Metadata
1 maintainer
Release files for nexus-a2a-sdk 0.5.0
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| File | Size | Uploaded | |
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| nexus_a2a_sdk-0.5.0.tar.gz | 138.7 kB | Details |
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| nexus_a2a_sdk-0.5.0-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 294.8 kB
Release files / nexus_a2a_sdk-0.5.0.tar.gz
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