JEP-Agent SDK 2.1 — JEP Core 0.7

Record signed Core 0.7 events about agent calls, export them, and verify their integrity.

Install

pip install jep-agent-sdk

The Python import is jep_agent; the command is jep-agent.

Local create → export → independent verification

No API, account or hosted service is required after installing dependencies. The runnable example is maintained in this repository:

git clone --branch v2.1.8 --depth 1 https://github.com/hjs-spec/jep-agent-sdk.git
cd jep-agent-sdk
python -m pip install jep-agent-sdk==2.1.8
python examples/local_roundtrip.py create ./local-evidence
python examples/local_roundtrip.py verify ./local-evidence

The verify command reopens the exported files in a separate process. The directory contains event.json, public-key.pem and keys.json; the temporary private key is never exported. Verification reports status: valid, cryptographic: pass and the original Event Hash. Existing directories are never overwritten.

An independently implemented Core verifier can check the same files:

python -m pip install jep-core-conformance==0.7.7
jep-validate validate ./local-evidence/event.json --keys ./local-evidence/keys.json

The demonstration uses a temporary key. A public key shipped with a record proves signature consistency; identifying a real actor requires an independently trusted key/profile. Changing the signed claim causes verification to fail.

Signed trace

from pathlib import Path
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
from jep_agent import AuditChain, record

key = Ed25519PrivateKey.generate()
chain = AuditChain("agent:example", private_key=key)

@record(issuer=chain.issuer, chain=chain)
def task(value):
    return value * 2

assert task(21) == 42
assert chain.verify_chain(key.public_key())
chain.save("events.jsonl")
Path("public-key.pem").write_bytes(key.public_key().public_bytes(
    serialization.Encoding.PEM, serialization.PublicFormat.SubjectPublicKeyInfo
))

Recording without a key is allowed for local traces, but produces unsigned, unverified records. Use a securely persisted key in a real deployment; this example generates a temporary key.

• @record retains function names and lifecycle status by default. Enable capture_values=True only for arguments and results that are safe to retain.
• RecordingError.call_executed=True means the business call already ran; do not automatically retry it.
• Load an existing archive before appending. Replacing it requires save(..., overwrite=True).

See the integration guide for asynchronous calls, unsupported generators and failure handling.

Inspect and verify

jep-agent verify events.jsonl --public-key public-key.pem
jep-agent export events.jsonl --output report.html
jep-agent web --port 8080

The CLI checks Core signatures and any local audit-chain links. It does not resolve arbitrary external references. The viewer and HTML export show recorded relationships and Signed (unverified) status; visual links do not establish causality or legal responsibility.

Acceptance and local extensions

JEPVerifier acceptance state is process-local and is lost on restart. Repeated delivery of the same identity and unsigned content returns already_accepted; different content under the same identity is rejected. For shared durable state, use the reference API.

The SDK stores audit links in ext['jep-agent.chain'] and local task links in ext['jep-agent.jac']. See the API reference for supported checks and Core contract for event semantics.

Optional framework adapters

The experimental OpenAI adapter targets synchronous Chat Completions; the LangChain auto patch targets historical AgentExecutor APIs. Install their extra dependencies only when using those adapters:

pip install 'jep-agent-sdk[langchain,openai]'

Development

From a source checkout:

pip install '.[dev,langchain,openai]' build
make lint
python -m pytest -q
python validate.py
python -m build --wheel
python scripts/check_coexistence.py dist/*.whl

CI uses fixed Core 0.7 J/D/T/V vectors and a commit-pinned independent Core validator. It also installs the built wheel beside the Python SDK and CLI in both orders and checks independent uninstalls.

• Architecture and research-helper boundaries
• API
• Migration and historical compatibility
• Implementation limits
• Canonical JEP Core repository

BSD-3-Clause. Author: Yuqiang Wang, HJS Foundation, signal@humanjudgment.org.