Trust Fabric integration

How gateway-to-gateway (G2G) DIDComm messaging, Verifiable Presentations, and x402 payments put Agent Stream on the Affinidi Trust Fabric.

A plain LLM proxy stops at routing and metering a call. Agent Stream carries the same trust-native capabilities as the rest of the Affinidi Trust Fabric, so identity, policy, and payments extend beyond a single deployment across organizational boundaries. Verify caller credentials with VP evidence →

Fabric

The Fabric is the set of DIDComm-based appliances that participate in mutual connectivity through Connection Points. A Fabric may include Trust Gateways, Trust Registries, and future appliance types. Appliances in the Fabric can route calls to each other using fabric:// endpoints (for example, fabric://gateway_id/surface_id).

How a Gateway-to-Gateway (G2G) call is routed

Gateway-to-Gateway (G2G) describes a call routed through the Fabric from one appliance to another. A G2G call is triggered when a Surface targets a fabric endpoint (fabric://gateway_id/surface_id). The originating appliance resolves the fabric endpoint address and forwards the call over the already-established DIDComm connection for that gateway; it does not open a new connection on demand, so the call fails if no Connection Point is currently connected to the target.

Agent Stream A
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Connection Point
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Mediator (if needed)
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Agent Stream B

Connection Point

A Connection Point is the DIDComm endpoint that another Fabric-enabled appliance uses to establish and use a connection with this appliance. Connection is initiated via an out-of-band DIDComm invitation, followed by a handshake that establishes a persistent bilateral connection.

A Connection Point is distinct from an Access Point. An Access Point is the inbound endpoint for external callers reaching a Surface; a Connection Point is the appliance-to-appliance pairing endpoint for Fabric membership. Confusing the two leads to misconfiguration.

Mediator

A Mediator is a DIDComm v2.1 relay service that routes messages between appliances that cannot connect directly. Its DID document must identify the configured DID and use WSS for message sockets plus HTTPS for authentication; this is revalidated before authentication, trust ping, and listener startup or recreation.

Agent DID

An Agent DID is a decentralised identifier (W3C DID) that represents the appliance or an agent in Fabric identity flows.

Verifiable Presentation (VP)

A Verifiable Presentation is a signed credential bundle Agent Stream attaches to an outbound call when identity injection is enabled on its Target, whether or not that Target is a Fabric endpoint. It proves the identity being forwarded and may include caller-binding claims.

How x402 payments and the model marketplace work

Where a deployment enables it, Agent Stream layers a payment mechanism on top of a call, and can build a provisioning flow on top of that same mechanism in turn.

x402 is an HTTP 402 payments protocol for blockchain-settled, metered access, used through either an embedded or a remote facilitator: the component that verifies and settles the payment. Settlement is the step that finalises a verified payment or records it for deferred completion. This lets model or service access be monetised at the request boundary itself, rather than only through a monthly invoice.

Agent Stream can also expose a built-in model marketplace: a catalogue and purchase flow that lets a caller provision an API key for a purchased model directly, without a separate procurement step outside the appliance. A marketplace purchase is itself settled through x402, so it is a use of that payment mechanism rather than a separate, parallel one.

Why this matters

Verifiable identity, decentralised gateway-to-gateway (G2G) trust, and native payment rails are what separate Agent Stream from a proxy that only forwards and meters traffic. An organisation that already runs other Trust Fabric appliances, such as Agent Gateway, can extend the same fabric and identity model to its LLM traffic, instead of treating model governance as a separate, disconnected system.