Spec v1.2.1 · W3C DID Method · MIT-licensed

The EU AI Act Compliance Trust Layer for AI Agents

Anchored in W3C DIDs and Verifiable Credentials. Spec v1.2.1 live, with reference implementation. Verankert in W3C DIDs und Verifiable Credentials. Spec v1.2.1 ist live, inklusive Referenzimplementierung.

TRAIL gives organizations deploying AI agents a verifiable, auditable identity layer aligned with the EU AI Act. Built on open W3C standards (DIDs, Verifiable Credentials, Bitstring Status Lists). did:trail v1.2.1 is published with a conformance test suite and a Node SDK on npm. The project contributes to the broader agent-identity standardization effort. TRAIL gibt Organisationen, die KI-Agenten einsetzen, einen prüfbaren, audit-fähigen Identity-Layer, der zur EU-KI-Verordnung passt. Auf Basis offener W3C-Standards (DIDs, Verifiable Credentials, Bitstring Status Lists). did:trail v1.2.1 ist mit Conformance-Test-Suite und Node-SDK auf npm veröffentlicht. Das Projekt versteht sich als Beitrag zur breiteren Agent-Identity-Standardisierung.

Read the SpecSpezifikation lesen Technical WhitepaperTechnisches Whitepaper
W3C DID Registry - PR #669 mergedgemergt EUIPO Trademark - Classes 9, 35, 42 filedKlassen 9, 35, 42 angemeldet Reference ImplementationReferenzimplementierung - 49 tests passingTests bestanden Spec - v1.2.1 (Managed Agent SupportManaged-Agent-Unterstützung) W3C DID Registry - PR #669 mergedgemergt EUIPO Trademark - Classes 9, 35, 42 filedKlassen 9, 35, 42 angemeldet Reference ImplementationReferenzimplementierung - 49 tests passingTests bestanden Spec - v1.2.1 (Managed Agent SupportManaged-Agent-Unterstützung)
Warum JETZT?Why NOW? EU AI Act: Enforcement ab Aug. 2026EU AI Act: Enforcement from Aug. 2026 W3C DID Core 1.0: Globaler StandardW3C DID Core 1.0: Global Standard 750M+ AI-Agenten ohne Identität750M+ AI Agents without Identity
Who did that, and was it really your agent?Wer hat das getan, und war es wirklich euer Agent?

AI agents increasingly act on their own on behalf of organizations: they write, decide, communicate. When something goes wrong or an audit arrives, today it is hard to prove beyond doubt which agent acted, which organization stands behind it, and what exactly happened when. KI-Agenten handeln zunehmend selbstständig im Namen von Organisationen: Sie schreiben, entscheiden, kommunizieren. Wenn etwas schiefgeht oder ein Audit kommt, lässt sich heute kaum zweifelsfrei nachweisen, welcher Agent gehandelt hat, welche Organisation dahintersteht und was genau wann passiert ist.

What TRAIL does NOT solveWas TRAIL NICHT löst

TRAIL does not make the AI model transparent or reproducible. It is not about how a model thinks or whether its outputs are reproducible.TRAIL macht nicht das KI-Modell transparent oder reproduzierbar. Es geht nicht darum, wie ein Modell denkt oder ob seine Ausgaben reproduzierbar sind.

What TRAIL does solveWas TRAIL löst

TRAIL gives every agent a verifiable identity (who it is, which organization stands behind it) and a tamper-evident log of its actions (what was done when).TRAIL gibt jedem Agenten einen prüfbaren Ausweis (wer ist das, welche Organisation steht dahinter) und ein fälschungssicheres Logbuch seiner Handlungen (was wurde wann getan).

Like an employee badge plus an audit-proof record. Not a look inside the model, but proof of who acted on behalf of the organization. Wie ein Mitarbeiter-Ausweis plus revisionssicheres Protokoll. Nicht ein Blick ins Modell, sondern ein Nachweis, wer im Namen der Organisation gehandelt hat.

Identity infrastructure for autonomous AI agentsIdentitätsinfrastruktur für autonome KI-Agenten
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Decentralized IdentityDezentrale Identitat

Every AI agent gets a W3C-compliant DID (did:trail) anchored in a vendor-neutral trust registry. No vendor lock-in, no single point of failure.Jeder KI-Agent erhalt eine W3C-konforme DID (did:trail), verankert in einem herstellerneutralen Trust Registry. Kein Vendor-Lock-in, kein Single Point of Failure.

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Cryptographic TrustKryptografisches Vertrauen

Ed25519 signatures with DataIntegrityProof (eddsa-jcs-2023). Crypto-agile architecture ready for post-quantum migration.Ed25519-Signaturen mit DataIntegrityProof (eddsa-jcs-2023). Krypto-agile Architektur für post-quanten Migration vorbereitet.

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AuditabilityPruefbarkeit

Full transparency on who built an AI agent, what it's authorized to do, and how it has performed. Cryptographically signed and verifiable.Volle Transparenz daruber, wer einen KI-Agenten gebaut hat, was er darf und wie er sich verhalten hat. Kryptografisch signiert und verifizierbar.

Example: did:trail IdentifierBeispiel: did:trail Identifier

// Organization DID (hash-suffix for collision resistance) did:trail:org:acme-corp-a7f3b2c1e9d04f5a // AI Agent DID (scoped to organization) did:trail:agent:sales-bot-e4d8f1a9b3c57d2e // Self-signed DID (local verification, no registry needed) did:trail:self:z6Mkf5rGMoatrSj1f4CyvuHBeXJELe9RPdzo2PKGNCKVtZxP
How TRAIL maps to regulatory requirementsWie TRAIL regulatorische Anforderungen erfüllt
The EU AI Act (Regulation 2024/1689) requires transparency, traceability, and human oversight for AI systems. TRAIL provides the technical infrastructure to support these obligations. Der EU AI Act (Verordnung 2024/1689) fordert Transparenz, Nachvollziehbarkeit und menschliche Aufsicht für KI-Systeme. TRAIL liefert die technische Infrastruktur zur Erfüllung dieser Pflichten.
ArticleArtikel RequirementAnforderung TRAIL CapabilityTRAIL-Fähigkeit Status
Art. 13 Transparency: AI systems must allow human oversight and include sufficient transparency did:trail DID provides unique verifiable identity; TrailAIPolicyService enables machine-readable disclosure of AI system type and risk class DESIGN
Art. 14 Human Oversight: Providers must design high-risk AI with tools for effective oversight Verifiable Credentials create tamper-proof audit trail; trust score tracks behavioral consistency over time DESIGN
Art. 26 Deployer Obligations: Deployers must use systems in accordance with instructions KYB-verified identity links agents to accountable legal entities; revocation mechanism enables immediate suspension DESIGN
Art. 49 Registration: Providers must register high-risk AI in EU database TRAIL Registry serves as complementary technical registry alongside official EU database GAP
TRAIL is NOT the official EU AI database. Art. 49 registration required separately.
Art. 52 Transparency for Certain AI: Users must be informed when interacting with AI TRAIL DID can be presented in real-time; TRAIL Badge provides visual trust indicator Q3 2026
GDPR Art. 5 Data Minimisation: Personal data must be adequate, relevant, and limited No personal data in DID documents; signatures contain only public keys DESIGN
GDPR Art. 25 Privacy by Design: Data protection by design and by default Fingerprint scheme enables verification without data disclosure; selective disclosure profile DESIGN
Important: TRAIL registration does NOT constitute compliance with the EU AI Act. Compliance is the responsibility of the deploying organization. TRAIL provides technical infrastructure that supports compliance - it is not a compliance certification. Hinweis: Eine TRAIL-Registrierung erfüllt NICHT den EU AI Act. Die Konformität liegt in der Verantwortung der einsetzenden Organisation. TRAIL liefert technische Infrastruktur zur Unterstützung der Konformität - keine Zertifizierung.
Protocol development timelineProtokoll-Entwicklungs-Timeline
TRAIL is an open-source protocol. The specification and reference implementation are publicly available under CC BY 4.0 (spec) and MIT (code). Community feedback drives development. TRAIL ist ein Open-Source-Protokoll. Spezifikation und Referenzimplementierung sind öffentlich verfügbar unter CC BY 4.0 (Spec) und MIT (Code). Community-Feedback treibt die Entwicklung.
March 2026 - CompletedAbgeschlossen

v1.0.0: FoundationFundament

  • W3C DID Method Specification publishedW3C DID-Methoden-Spezifikation veröffentlicht
  • did:trail registered in W3C DID Extensions Registry (PR #669 merged)did:trail im W3C-DID-Extensions-Registry registriert (PR #669 gemergt)
  • Reference implementation: @trailprotocol/core (TypeScript)Referenzimplementierung: @trailprotocol/core (TypeScript)
  • Self-mode DID resolution (offline, no registry needed)Self-mode DID-Auflösung (offline, kein Registry nötig)
  • EUIPO Trademark filed (Classes 9, 35, 42)EUIPO-Marke angemeldet (Klassen 9, 35, 42)
March 2026 - CompletedAbgeschlossen

v1.1.0: HardeningHärtung

  • Crypto agility framework (SUPPORTED_CRYPTOSUITES registry)Krypto-Agilitätsframework (SUPPORTED_CRYPTOSUITES Registry)
  • Key rotation for Org/Agent modeKey Rotation für Org/Agent-Modus
  • Specification versioning (trail:specVersion)Spezifikationsversionierung (trail:specVersion)
  • Key recovery mechanisms (multi-controller, social, registry-assisted)Key-Recovery-Mechanismen (Multi-Controller, Social, Registry-gestützt)
  • Governance framework (dispute resolution, change management)Governance-Framework (Streitbeilegung, Änderungsmanagement)
  • 49 tests across 12 test suites49 Tests in 12 Test-Suites
  • GitHub Discussions enabled for community feedbackGitHub Discussions für Community-Feedback freigeschaltet
  • NIST NCCoE AI Identity Comment submittedNIST NCCoE AI Identity Kommentar eingereicht
  • W3C CCG community introduction postedW3C CCG Community-Vorstellung veröffentlicht
  • @trailprotocol/core v0.1.0 published on npm@trailprotocol/core v0.1.0 auf npm veröffentlicht
  • First external contributor onboarded (Amey Parle - PRs #5, #7, Issue #4)Erster externer Contributor ongeboardet (Amey Parle - PRs #5, #7, Issue #4)
Q2 2026 - CompletedAbgeschlossen

v1.2.0: Distribution & CommunityDistribution & Community

  • @trailprotocol/core on npm (v0.1.0)@trailprotocol/core auf npm (v0.1.0)
  • Managed Agent Identity Binding spec (PlatformIdentityBinding VC, §7.5)Managed-Agent-Identity-Binding Spec (PlatformIdentityBinding VC, §7.5)
  • CI/CD pipeline (GitHub Actions)CI/CD-Pipeline (GitHub Actions)
  • JSON-LD Context deployment on trailprotocol.orgJSON-LD-Context-Deployment auf trailprotocol.org
  • CONTRIBUTING.md + community guidelinesCONTRIBUTING.md + Community-Richtlinien
  • W3C CCG community discussion: Layering pattern (did:pnl role profiles over did:trail identity anchors) - Discussion #15W3C CCG Community-Diskussion: Layering-Pattern (did:pnl Rollenprofile über did:trail Identitätsanker) - Discussion #15
  • Cross-Method Binding specification (§5.4): did:trail as identity anchor, alsoKnownAs binding to any DID method - merged in v1.2.0Cross-Method-Binding-Spezifikation (§5.4): did:trail als Identitätsanker, alsoKnownAs-Binding zu beliebigen DID-Methods - gemergt in v1.2.0
  • Agent Declaration in Content Signatures (§8.13) - AI accountability for generated contentAgent Declaration in Content Signatures (§8.13) - KI-Accountability für generierte Inhalte
  • Federation Trust Anchor Model (§3.4) + Revocation Propagation (§8.7) - merged in v1.2.0Federation Trust Anchor Model (§3.4) + Revocation Propagation (§8.7) - gemergt in v1.2.0
  • Credential revocation (W3C StatusList2021) - normative in §8.7Credential-Widerruf (W3C StatusList2021) - normativ in §8.7
  • Universal Resolver driver (did:trail) - Docker image on GHCR, DIF PR #546 (in review)Universal-Resolver-Treiber (did:trail) - Docker-Image auf GHCR, DIF PR #546 (in Review)
Q3 2026 - CurrentAktuell

v1.3.0: Binding Proofs & ConformanceBinding Proofs & Konformität

  • BindingProofCredential specification (§5.4.5): cryptographically signed reciprocal cross-method bindings - closes the spoofing gap named in §5.4.4BindingProofCredential-Spezifikation (§5.4.5): kryptografisch signierte reziproke Cross-Method-Bindings - schließt die in §5.4.4 benannte Spoofing-Lücke
  • BindingProofCredential implementation in @trailprotocol/core: create + verify API, signed test vectors, 59 testsBindingProofCredential-Implementierung in @trailprotocol/core: Create- + Verify-API, signierte Testvektoren, 59 Tests
  • VC 2.0 JSON-LD context published (trailprotocol.org/ns/credentials/v2)VC 2.0 JSON-LD-Context veröffentlicht (trailprotocol.org/ns/credentials/v2)
  • @trailprotocol/core v0.2.0 npm release (BindingProof API)@trailprotocol/core v0.2.0 npm-Release (BindingProof-API)
  • Registry API OpenAPI 3.0 specification (§6 endpoints)Registry-API OpenAPI-3.0-Spezifikation (§6-Endpunkte)
  • Verifier Trust List JSON Schema (§3.4.4)Verifier-Trust-List JSON-Schema (§3.4.4)
  • Conformance test suite (spec-level test vectors + harness)Konformitäts-Test-Suite (Spec-Level-Testvektoren + Harness)
Q3-Q4 2026 - PlannedGeplant

v2.0.0: Registry

  • TRAIL Registry Server (HTTP API for Tier 1/2)TRAIL-Registry-Server (HTTP-API für Tier 1/2)
  • Trust Score Engine (5-dimension computation)Trust-Score-Engine (5-dimensionale Berechnung)
  • Python + Go reference implementationsPython- und Go-Referenzimplementierungen
  • W3C DID Test Suite complianceW3C-DID-Test-Suite-Konformität
  • Post-quantum cryptosuite migration pathPost-Quanten-Kryptosuite-Migrationspfad
Specification & DocumentationSpezifikation & Dokumentation
Specification

DID Method Specification v1.2.1

The complete did:trail method specification, including CRUD operations, trust model, security considerations, crypto agility, key rotation, Managed Agent Identity Binding, and governance.Die vollständige did:trail-Methodenspezifikation mit CRUD-Operationen, Trust-Modell, Sicherheitsbetrachtungen, Krypto-Agilität, Key Rotation, Managed-Agent-Identity-Binding und Governance.

View on GitHubAuf GitHub ansehen
Whitepaper

Technical Whitepaper v1.0Technisches Whitepaper v1.0

In-depth technical overview of the TRAIL architecture, trust model, credential framework, threat model, and EU AI Act alignment.Detaillierte technische Übersicht der TRAIL-Architektur, des Trust-Modells, Credential-Frameworks, Bedrohungsmodells und EU-AI-Act-Ausrichtung.

Read WhitepaperWhitepaper lesen
Open Source

GitHub Repository

Full source code, reference implementation (49 tests), DID document examples. Spec: CC BY 4.0. Code: MIT License.Vollständiger Quellcode, Referenzimplementierung (49 Tests), DID-Dokument-Beispiele. Spec: CC BY 4.0. Code: MIT-Lizenz.

View RepositoryRepository anzeigen
Community

GitHub Discussions

Join the conversation. Ask questions, propose features, share your use case, or challenge the protocol design.Nimm an der Diskussion teil. Stell Fragen, schlage Features vor, teile deinen Use Case oder hinterfrage das Protokolldesign.

Join DiscussionsDiskussionen beitreten