Sentinel · v3.4.3 · Trace-to-Trust kernel for regulated AI

The evidence infrastructure
for regulated AI.

Sentinel is the Trace-to-Trust kernel that turns EU AI Act compliance from a blocker into a baseline. Every agent decision is traced, attested, and sealed at runtime — so your teams stop fighting audits and keep shipping.

Key benefits
  • Pre-execution, not post-mortem. Evidence is produced the moment each agent acts — not reconstructed when auditors arrive.
  • Cryptographically bound, legally durable. Ed25519 signatures, RFC-3161 timestamps, and PAdES-sealed packs provide long-term verifiable proof, designed for 10+ year retention.
  • One baseline for every stakeholder. Product, Risk, Security and Legal work from the same Trace-to-Trust layer — no more reconciling conflicting audit trails.
Apache 2.0
923 tests passing
100% branch coverage
Ed25519 attestations
RFC-3161 timestamping
Air-gapped deployable
BSI IT-Grundschutz preparation
EU AI Act Annex III enforcement — 2 August 2026
High-risk AI systems must produce automatic tamper-resistant evidence. Penalties up to €15M or 3% of global annual turnover.
Sentinel customers are already shipping production AI through the same governed path they'll run on August 3rd.
102
days until enforcement
Trace
Runtime capture
Wrap any agent call with a single decorator
Bind input, policy, output, and jurisdiction
Instrument LangChain, CrewAI, AutoGen
Attest
Cryptographic signing
Ed25519 signature on every attestation by default
Hash-chain each record to its namespace predecessor
Verify independently — no vendor required
Audit
Evidence retrieval
Query decisions by agent, policy, or outcome
Retrieve full attestation packages on demand
Stream events to SIEM, GRC, or custom systems
Comply
Regulatory delivery
Package evidence into PAdES-signed PDF bundles
Map to EU AI Act, BAIT, MaRisk, DORA
Deliver what a regulator can verify as a whole
credit_agent.py
capturing
# Your existing agent. Unchanged. from sentinel import Sentinel sentinel = Sentinel() @sentinel.trace(policy="credit_v2") def assess_credit(applicant: dict) -> Decision: return agent.evaluate(applicant) $ python credit_agent.py trace captured trc_8f2a1b3c input hash sha256:3c7f..a91e policy version credit_v2@rev.a47 signature Ed25519 · 64-byte attestation ready 1.8ms
att_9f2e8b1a.json
hash-verified
// Tamper-evident attestation · Ed25519 + SHA-256 { "attestation_id": "att_9f2e8b1a4c7d", "timestamp": "2026-04-20T14:03:22.847Z", "chain_namespace": "sentinel-ns:v1:credit_agent:EU-DE:credit", "previous_hash": "sha256:7a4e..dfc3", "decision": { "agent": "credit_agent@v2.1.4", "policy": "credit_v2@rev.a47", "input_hash": "sha256:3c7f..a91e", "output_hash": "sha256:8b2d..4f6c", "result": "APPROVED" }, "signature": "Ed25519:oz0PLc..SG5yZE" }
hash verified · independently recomputable
sentinel chain verify att_9f2e
Sentinel Control Plane
LIVE · last 24h
47,283
Decisions
47,283
Attestations
312
Denied
1.8ms
Median latency
Time
Agent
Policy
Outcome
Evidence
14:03:22 credit_agent credit_v2@a47 Approved0.94 att_9f2e
14:03:24 kyc_verification kyc_v1@c02 Approved0.89 att_3a7b
14:03:26 claims_processor claims_v3@f12 Review0.47 att_5e9f
14:03:29 credit_agent credit_v2@a47 Denied0.12 att_7c2d
14:03:31 aml_monitor aml_v4@b21 Approved0.91 att_1b4a
14:03:35 fraud_scorer fraud_v2@d33 Review0.58 att_8d2c
audit_package_att_9f2e8b1a.pdf
1 / 1
Audit Package
att_9f2e8b1a · credit_agent@v2.1.4
Generated 2026-04-20
Retention until 2036-04-20
PAdES-signed
Decision
APPROVED · confidence 0.94 · 2026-04-20T14:03:22.847Z
Policy Context
credit_scoring_v2@rev.a47 · signed by compliance@swentures
Input Integrity
sha256:3c7f..a91e · 1,284 bytes
Output Integrity
sha256:8b2d..4f6c · 412 bytes
Jurisdiction
EU-DE · on-premise · no cross-border egress
Regulatory Mapping
EU AI Act Art. 12+17 · MaRisk AT 4.3.1 · BAIT §6.3
Attestation hash independently verified · Ed25519 + SHA-256
sentinel comply verify pack.pdf
The Consequence

Pilots become production. Scale is no longer blocked by audit reconstruction. The next agent is a decision, not a debate.

With evidence running at runtime, compliance moves from blocker to companion — and new AI use-cases ship through the same governed path as every other agent.

Your stack
already has most
of this.

In most regulated organisations the AI stack is already assembled from third-party tools of different vendors: governance tools, observability platforms, LLM providers, identity systems. Each layer lives with its own vendor.

What is missing is the layer that turns this heterogeneous stack into a regulatorily usable whole — the knot-resolver that produces the single audit package a regulator can verify, without replacing any of your existing investments.

Regulatory Frame
EU AI ActBAITMaRisk DORANIS2BSI IT-GrundschutzGDPR
Defines what must be auditable
Identity & Access
Agent authorization
SPIFFEKeycloakEntra
Governance
Policy enforcement
Microsoft AGTOPACedar
Evidence Runtime
Signed audit packages
Sentinel
Observability
Trace & telemetry
LangfuseOpenTelemetry
LLM & Agent
Execution layer
AnthropicMistralLangChain
Layers 1, 2, 4, 5 are typically third-party in most enterprises. Layer 3 is the gap. Sentinel is not a new bottleneck — it is the knot-resolver that holds the heterogeneous third-party stack together, regulatorily.
What Sentinel is

The cryptographic evidence layer for regulated AI.

Every agent decision becomes a signed, hash-linked attestation. Every evidence pack PDF carries a PAdES signature with EU-sovereign RFC-3161 timestamp. Every chain of decisions can be verified independently by your auditor — air-gapped, offline, no vendor lock-in.

Sentinel maps directly to EU AI Act Art. 12 (record-keeping) and Art. 17 (quality management). It supports BSI IT-Grundschutz preparation, BaFin and MaRisk requirements, and any regulator who asks the fundamental question: “Can you prove what your AI did, and when?”

Where Sentinel fits in your stack

Sentinel is the cryptographic evidence layer that observability and governance tools don’t produce.

Not observability

Langfuse, Datadog, Arize, and LangSmith give you performance, cost, and drift signals. Sentinel gives you legally durable evidence of what each agent decided.

Not governance enforcement

Microsoft AGT, OPA, Cedar, and Bedrock Guardrails enforce policies at runtime. Sentinel seals the cryptographic proof that those policies were applied.

When an auditor asks for courtroom-defensible proof, that is the question Sentinel answers — and the question no observability or governance tool was designed to solve.

Start in 2 minutes

Four commands.
Zero accounts. Zero network.

Scaffold a local pilot, run ten decisions through @sentinel.trace, write a signed PDF evidence pack, score yourself against EU AI Act Art. 12.

Install

shell
# Core — @sentinel.trace, Ed25519 signing, hash chain, RFC-3161 $ pip install sentinel-kernel # With PDF evidence packs $ pip install 'sentinel-kernel[pdf]' # With PAdES PDF signing only (lighter than [pdf]) $ pip install 'sentinel-kernel[pades]' # With post-quantum signing (ML-DSA-65) $ pip install 'sentinel-kernel[pqc]' # Or everything at once $ pip install 'sentinel-kernel[pdf,pades,pqc]'
The core install produces a fully working Sentinel with Ed25519 default signing, RFC-3161 EU-sovereign timestamping, hash-chain attestations, and SQLite / PostgreSQL / filesystem storage. Extras opt in to heavier or optional capabilities: [pdf] pulls reportlab + pyhanko for evidence-pack PDFs; [pades] is [pdf] without reportlab; [pqc] adds ML-DSA-65 post-quantum signing via oqs-python.

Wrap one function

hello_sentinel.py
from sentinel import Sentinel sentinel = Sentinel() @sentinel.trace async def approve(request: dict) -> dict: return await your_agent.run(request) # Every call is now a signed, verifiable attestation.
One decorator. One line. Your LLM, ML classifier, rule engine, or robot control loop — Sentinel does not care what the function does, only that its decisions can be recomputed and verified later.
EU AI Act Coverage

What Sentinel covers.
What it does not.

Sentinel automates EU AI Act Art. 12/13/14/17 — the logging, transparency, oversight, and quality-management obligations. Other articles require organisational action. We mark the split honestly.

ArticleRequirementSentinel
Art. 12Automatic tamper-resistant loggingFull
Art. 13Transparency to deployer / userFull
Art. 14Human oversight (kill switch)Full
Art. 17Quality-management traceabilityFull
Art. 9Risk managementPartial
Art. 16Provider obligationsPartial
Art. 26Deployer obligationsPartial
Art. 72GPAI post-market monitoringConditional
Art. 11Technical documentation (Annex IV)Human action
Art. 10Data governanceHuman action
Art. 15Accuracy & robustnessHuman action
Sentinel never overclaims. Articles requiring human action are clearly marked. Partial articles are those where Sentinel produces the evidence but an organisational deliverable must still be written. Run sentinel audit-gap to see the exact split for your setup.
Where procurement is already active

Where the
deadline bites first.

EU AI Act enforcement applies to decisions that touch rights, access to services, safety, or meaningful financial outcomes. The architecture is technology-agnostic; the sectors below are where procurement is already active.

Banking & Financial Services

A German bank runs credit decisioning, fraud scoring, AML, and transaction approval through Sentinel. When BaFin requests evidence on model drift under BAIT §6.3, they deliver signed evidence packs in minutes — not weeks of log reconstruction.

EU AI ActDORABaFin BAITMaRisk

Defence & Aerospace

Procurement, logistics, dual-use assessment. Air-gapped and classified deployments with VS-NfD path. Cryptographic evidence that survives supply-chain scrutiny and export-control audits.

EU AI ActBSI IT-GrundschutzVS-NfD

Enterprise Software & AI Platform Providers

Enterprise software firms embed AI into products sold to regulated customers. Sentinel gives their customers the evidence packs needed to deploy those products under the EU AI Act — without reinventing compliance infrastructure per vendor.

EU AI ActISO 42001Customer conformity assessments

Public Sector & KRITIS

Benefit eligibility, permit approval, critical-infrastructure AI. Statutory transparency under NIS2 and sector law. Evidence packs that regulators, courts, and citizens can independently verify.

EU AI ActNIS2E-Government law

Industrial Manufacturing

Quality control, predictive maintenance, robotic decisioning. Standards-aligned retention across plant lifetimes — 15+ year evidence archival in formats that outlive every vendor swap.

EU AI ActISO 42001IEC 62443
Runtime

Evidence at runtime, not after the fact

Sentinel wraps each agent decision as it happens. Input, policy, output, and jurisdiction are bound into a signed attestation before the next call begins. No log collection, no post-hoc reconstruction, no manual mapping under audit pressure.

Capture input hash, output hash, policy version, jurisdiction at the moment of decision
Bind every decision to a reproducible attestation with Ed25519 integrity
Decorate existing agents — LangChain, CrewAI, AutoGen — with one line
Sub-millisecond overhead per attestation on commodity hardware
Independent

Verifiable without operator trust

An auditor can only trust evidence as far as they trust whoever produced it. Sentinel runs as an independent layer — not owned by the operator, not owned by the LLM vendor, not owned by the cloud provider. The signature chain holds whether anyone trusts you or not.

Vendor-neutral — structurally independent of governance, observability, and LLM layers
EU-jurisdiction native — on-premise deployment, no CLOUD-Act exposure
Audit integrity — evidence operated and evaluated by different parties, no structural conflict of interest
Apache 2.0, hash-verified — inspect the kernel, recompute any attestation, own your evidence
Integration

Built for your existing stack

Sentinel does not replace your governance tools, observability platform, or LLM provider. It sits between them — receiving policy results, enriching with traces, emitting signed evidence. Bidirectional by design: allow signals feed innovation, kill signals gate risk.

Python-native kernel with OpenTelemetry-compatible span export
Langfuse, OpenTelemetry, Prometheus — trace ingestion hooks ready today
Microsoft AGT, OPA, Cedar — governance bridges for bidirectional flow
SIEM, GRC, SOAR — stream events to existing enterprise infrastructure
Lifecycle

Stable across LLM generations

Regulatory retention runs ten years or longer. Your LLMs and agents will not. The evidence layer must outlive every model, every framework, every vendor swap — stable signature format, stable storage interface, stable regulatory mapping.

10-year retention by default — EU AI Act Article 17 compliant
Storage-agnostic — SQLite, PostgreSQL, S3-compatible, filesystem
Air-gapped deployment — evidence stays inside your security boundary
BSI IT-Grundschutz preparation and VS-NfD-capable deployment path
Roadmap

Primitives today.
Ecosystem with the community.

We are building Sentinel the way HashiCorp built Terraform: primitive hooks in the kernel, the ecosystem grows through the community. Three stages, honestly labelled.

Currently shipping in v3.4.3

Kernel primitives

Production-ready, Apache 2.0, 923 tests passing. Install with pip install sentinel-kernel.

@sentinel.trace decorator Ed25519 attestations (default, out of the box) Hash-chain attestation linkage RFC-3161 EU-sovereign timestamping (default) SHA-256 content hashing (hash-only privacy default) Kill switch (EU AI Act Art. 14) PAdES PDF signing ([pdf] extra) Optional ML-DSA-65 post-quantum signing ([pqc] extra) LangChain · CrewAI · AutoGen · Haystack · FastAPI · Django integrations SQLite · PostgreSQL · Filesystem storage backends OpenTelemetry span export Air-gapped / VS-NfD / EU-sovereign deployment paths BSI IT-Grundschutz preparation scaffolding
In development (v3.5+)

Architecture bridges for enterprise stacks

Four architectural items raised by design partners. All four have committed design docs under docs/architecture/. Each item re-ships to production only after passing our fresh-venv E2E verification harness — discipline over shipping speed.

OpenTelemetry causal-context bridge · when OTEL spans exist, read context and preserve parent-child linkage in cryptographic attestations JSON-LD + PROV-O semantic export · 10-15 year retention format, W3C-standard ontology, offline-verifiable evidence packs Fine-grained retention policies · YAML rules per agent / jurisdiction / policy family, with field-level redaction Write-once storage backends · application-layer tamper prevention (filesystem, S3 Object Lock, Azure Immutable Blob)
Further ecosystem bridges · community-driven
MCP gateway integration Microsoft AGT bridge Langfuse ingestion hooks OPA native decision-log export format Cedar policy binding Redis · Legal-hold APIs
With the community

Enterprise ecosystem

The devil sits in the details of complex enterprise landscapes. These integrations we build with the community, not for it.

SAP agents Salesforce Agentforce Azure AI Foundry Google ADK AWS Bedrock Agents ServiceNow GRC · OneTrust · Archer your use-case
Enterprise AI infrastructure is complex. Sentinel solves one layer — the regulatory evidence layer. The other layers need other tools, and those tools work best when integrated. We build the hooks for the ecosystem. The community fills them.
Get Started

Ready to use Sentinel?

Sentinel is in design partnership with a select group of regulated enterprises building production-grade agentic AI under the EU AI Act. Request a working session with our team, or explore the code on GitHub.