Open source. The Python package runs in your environment; this page
is a browser walkthrough with fictional data.
A small action. A clear boundary.
Browser walkthrough · fictional
sample data
Starting
01
Your policy
Allow reading project notes
Controls whether the browser walkthrough may read the fictional
project notes.
02
Agent action
project-notes.txt
Read the project notes.
This result reflects the previous policy setting. Run the action
again to apply the new boundary.
Fictional file outputproject-notes.txt
03
Evidence
Run the action to create a browser-session receipt.
Browser-session receipt
Decision record
Not verified
Outcome
—
Action
—
Sequence
—
Created
—
View signed JSON +
The page creates a non-exportable, ephemeral HMAC key in this
browser session. Verification detects changes made after signing;
it does not establish an independent identity, execute a model, or
provide an operating-system sandbox. Use the Python package for
native enforcement in your own execution path.
Apply this to your agent workflow.
Start with a paid diagnostic or a free introduction, depending
on how much decision support you need.
Snapshot scope: the cited v1.4.2 package is classified Alpha. Public repository CI reported 2,463 passed, 3 skipped. These measurements describe the linked source and run, not a general performance or suitability claim.
Run the native governed lifecycle
This example runs against the package API and composes authorize,
execute, record, bind, and verify explicitly.
import hashlib
import secrets
from pathlib import Path
from tempfile import TemporaryDirectory
from hummbl_governance import DelegationTokenManager, ReceiptEngine
secret = secrets.token_bytes(32) # Load a stable key in production.
contract = {"id": "summary-v1", "operations": ["summarize"]}
task_id = "task-42"
# AUTHORIZE — issue and validate scoped delegated authority.
tokens = DelegationTokenManager(secret)
dct = tokens.issue(
issuer="orchestrator",
subject="summarizer-agent",
operations=contract["operations"],
resources=["docs/report.md"],
task_id=task_id,
contract_id=contract["id"],
)
allowed, reason = tokens.validate_token(
dct,
expected_task_id=task_id,
expected_contract_id=contract["id"],
expected_subject="summarizer-agent",
)
if not allowed:
raise PermissionError(f"Delegated authority denied: {reason}")
# EXECUTE — your runtime performs the authorized action.
source = "Bounded authority makes agent actions reviewable."
result = " ".join(source.split()[:5])
# RECORD + BIND + VERIFY — authenticate the tuple and verify its chain.
with TemporaryDirectory() as state:
receipts = ReceiptEngine(Path(state), signing_secret=secret)
receipt = receipts.create_and_store(
agent_id=dct.subject,
action_type="summarize",
payload={
"contract": contract,
"dct": dct.to_dict() | {"signature": dct.signature},
"evidence": {
"outcome": "completed",
"output_sha256": hashlib.sha256(result.encode()).hexdigest(),
},
},
)
if not receipts.validate(receipt):
raise RuntimeError("Receipt authentication failed")
chain_valid, chain_reason = receipts.verify_chain(dct.subject)
if not chain_valid:
raise RuntimeError(f"Receipt chain failed: {chain_reason}")
if len(receipts.list_for_agent(dct.subject)) != 1:
raise RuntimeError("Receipt persistence check failed")
Version 1.4.2 does not expose a dedicated GovernanceTuple object or a one-call lifecycle. The application composes the tuple in the authenticated receipt payload.
HMAC-SHA256 delegation tokens bind issuer, subject, task, and authority fields inside a shared-secret trust domain. HMAC receipts make integrity and authenticity checkable by parties that hold the shared key. HMAC verifies integrity and authenticity inside that boundary; it is not public-key proof.
Evidence scope and implementation responsibilities
Public-surface receipt
The published package is Alpha. A scoped public GET on the now-retired probe https://hummbl-receipt-probe.hummbl.workers.dev/ produced 2026-08-31T21:56:55Z (receipt r-7e400da03299). Inspect the archived receipt. That scoped event does not support a general “production-tested” claim.
Governance Gates in CI/CD
A primitive only mediates actions routed through it. The
implementer remains responsible for complete integration, key
protection, identity, evidence capture, monitoring, and
response.
EU AI Act Readiness
HUMMBL supports technical evidence generation and engineering
mappings. It does not determine legal applicability, confer
compliance, certify an AI management system, or replace an
auditor, standards body, counsel, or regulator.
Review every claim, source, scope, and limitation in the
public claim ledger.
Historical fleet observation
This archived sample does not establish current fleet health.
Historical fleet observation from committed evidence:
evidence stale