PRODUCT

GHARRA.
Find and Trust Healthcare AI Agents Worldwide.

The Global Healthcare Agent Registry & Routing Authority (GHARRA) is like DNS for healthcare AI agents — a federated, zero-trust registry where healthcare systems discover, verify, and securely connect to AI services across organisations and national borders. Patient data never enters the registry.

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14+
API Endpoints
9
Policy Rules
0
Patient Data Stored
5
Protocols Supported
HOW DISCOVERY WORKS

Discover. Route. Trust.

When a healthcare system needs an AI agent — a diagnostic model, a scheduling assistant, a claims processor — GHARRA provides the lookup, verification, and secure connection in three steps.

Step 1

Discover

Query the registry by capability, jurisdiction, or protocol. GHARRA returns matching agents with their trust metadata and connection details.

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Step 2

Route

The policy engine evaluates jurisdiction rules, protocol compatibility, and organisational permissions to determine a valid connection path.

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Step 3

Trust Bundle

GHARRA issues a cryptographic trust bundle containing the agent's public key, endorsed capabilities, and a time-limited access token.

FEDERATION MODEL

Three-tier sovereignty.

GHARRA operates as a federated hierarchy. Each tier controls its own data, policies, and trust boundaries. No tier can see or override the data of another without explicit delegation.

Root

Root Registry — Ireland

Maintains the global schema, protocol specifications, and root certificate authority. Does not store agent records or patient data. Publishes the federated discovery protocol that all sovereign nodes implement.

Sovereign

Sovereign Registries — National

Each country or jurisdiction operates its own sovereign registry. Controls which agents are approved for use within its borders, enforces local data residency rules, and manages national trust policies.

Org

Organisational Registries

Hospitals, health systems, and care networks register and manage their own agents. Organisational registries inherit sovereign policies but can apply stricter local rules. Agent credentials are issued at this level.

ZERO PATIENT DATA ARCHITECTURE

Patient data never enters the registry.

GHARRA stores only agent metadata — capabilities, endpoints, certificates, and policies. A three-layer detection pipeline scans every registration and update to ensure no patient data is ever persisted.

Structural Scan

Analyses the shape of incoming payloads against known clinical data structures (FHIR resources, HL7 segments, CDA sections) and rejects any that match patient-data patterns.

Keyword-in-Value Detection

Scans all string values for clinical identifiers, patient names, dates of birth, medical record numbers, and other terms associated with protected health information (PHI).

Format Regex

Pattern-matches against known identifier formats — NHS numbers, Medicare IDs, Social Security formats, ICD codes embedded in free text — and blocks any match from persistence.

POLICY ENGINE

Nine Attribute-Based Access Control (ABAC) rules.

Every discovery request and agent connection is evaluated against the full policy set. Rules are composable, auditable, and enforceable at every tier of the federation.

Jurisdiction Match

Requesting system and target agent must share an approved jurisdiction path in the federation hierarchy.

Protocol Compatibility

The requested communication protocol must be supported by both the caller and the target agent.

Credential Validity

Agent certificates must be current, properly chained to the issuing organisational registry, and not revoked.

Capability Scope

The requested action must fall within the agent's registered and endorsed capability set.

Data Residency

Connection routing must comply with the sovereign registry's data residency and cross-border transfer rules.

Rate & Quota

Per-agent and per-organisation rate limits prevent abuse and ensure fair access across the federation.

Time-of-Day

Connections can be restricted to approved operating windows defined by the organisational registry.

Audit Trail

Every policy evaluation is logged with the full decision context — who requested, what was evaluated, and what was decided.

Emergency Break-Glass

In clinically urgent situations, authorised users can bypass standard policy with full audit logging and mandatory post-incident review.

SUPPORTED PROTOCOLS

Five ways to connect.

GHARRA is protocol-agnostic at the registry layer. Agents register the protocols they support, and the discovery engine matches callers to compatible endpoints.

nexus-a2a-jsonrpc

Symphonix Nexus Agent-to-Agent protocol. JSON-RPC 2.0 with Server-Sent Events for real-time clinical delegation between agents.

http-rest

Standard RESTful HTTP APIs. The most widely supported integration pattern for healthcare systems and electronic health records.

bullettrain-external

Direct integration with the BulletTrain platform's external connector API for systems already running on the Symphonix stack.

fhir-r4

Fast Healthcare Interoperability Resources (FHIR) Release 4. Native support for FHIR-based agent interactions and SMART on FHIR authorisation.

grpc

High-performance Remote Procedure Calls (gRPC) with Protocol Buffers. Ideal for low-latency, high-throughput agent-to-agent communication.

AUTHENTICATION

Cryptographic trust at every layer.

GHARRA supports multiple authentication mechanisms to meet the security requirements of diverse healthcare environments, from cloud-native systems to on-premises infrastructure.

JSON Web Tokens (JWT)

Signed tokens using RS256, ES256, or EdDSA algorithms. Supports short-lived access tokens with refresh rotation, audience-scoped claims, and federation-aware issuer chains. Compatible with existing OAuth 2.0 infrastructure.

Mutual TLS (mTLS)

Certificate-based mutual authentication per RFC 8705. Both the calling system and the target agent present X.509 certificates chained to the federation's certificate authority. Provides transport-layer identity verification.

Demonstrating Proof-of-Possession (DPoP)

Token binding per RFC 9449 prevents token replay and theft. Each request includes a proof that the sender holds the private key associated with the token, providing defence against man-in-the-middle attacks.

Federation Key Exchange

Cross-tier key distribution ensures that sovereign and organisational registries can independently verify tokens issued by other tiers without calling back to the root. Supports offline verification for air-gapped deployments.

RS256ES256EdDSA RFC 8705 mTLSRFC 9449 DPoP X.509OAuth 2.0SMART on FHIR

See the registry in action

Cross-Border Orchestration Demo Agent Network Topology Demo
Book a 30-Minute Architecture Walkthrough

Managed service. Zero patient data.

GHARRA is hosted and operated by Symphonix Health. Subscribe to discover and use agents across the global registry — we handle federation, trust, and governance. An integration bridge connects every BulletTrain deployment to the full agent ecosystem.

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Hosted • Pay-per-use • Zero patient data • Federated • Sovereign-ready