Add alknet-core architecture specs in docs/architecture/crates/core/ with focused subdocuments for core types, endpoint, auth, and config. Write ADR-010 (ALPN Router and Endpoint) defining AlknetEndpoint, HandlerRegistry, accept loop, and graceful shutdown. Write ADR-011 (AuthContext Structure) defining AuthContext fields, immutability in handle(), and IdentityProvider injection pattern. Resolve OQ-04 (static registration), OQ-12 (file paths only for v1). Add OQ-11 (auth observability). Fix remaining alknet-secret references to alknet-vault across ADRs 003/004/005/009.
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ADR-005: irpc as Call Protocol Foundation
Status
Accepted
Context
The call protocol (alknet-call) provides structured RPC — operations, request/response, streaming subscriptions, and pub/sub. This is the primary interface for programmatic interaction with an alknet node. It needs to work across platforms: Rust clients, TypeScript/JavaScript clients (via NAPI), WASM targets, and any language that can speak the wire format.
The previous implementation used irpc for the call protocol's operation registry, framing, and service patterns. irpc provides:
- An operation registry with schema-based discovery
- Length-prefixed JSON framing (EventEnvelope)
- Request/response and streaming patterns
- Type-safe operation definitions via derive macros
The call protocol is derived from a TypeScript implementation of "operations" and "pub/sub" that can wholesale import OpenAPI schemas, wrap MCP servers, and go the other direction — exposing operations as HTTP endpoints, MCP tools, etc. This bidirectional capability is strategically important.
Decision
alknet-call uses irpc as its foundation. The CallAdapter implements ProtocolHandler on ALPN alknet/call and delegates to irpc's operation registry, framing, and dispatch.
irpc is not replaced or wrapped in an abstraction layer — it IS the call protocol's core. The relationship is:
- irpc provides: operation registry, schema discovery, frame encoding/decoding, request/response routing, streaming
- alknet-call provides: the ProtocolHandler adapter (BiStream → irpc), AuthContext integration, access control checks, the ALPN registration
This means:
- The wire format is irpc's EventEnvelope framing — length-prefixed JSON
- Operation schemas follow irpc's schema model — JSON Schema compatible
- The TypeScript "operations" and "pub/sub" patterns that can import OpenAPI schemas and expose MCP tools are supported at the protocol level
- Future NAPI and WASM clients speak the same wire format
The VaultProtocol in alknet-vault also uses irpc as its service protocol. This is consistent — alknet-vault's irpc service is an independent service that happens to use the same framing, not a dependency on alknet-call.
Consequences
Positive:
- Proven operation registry and framing — irpc is already tested in production (iroh uses it)
- JSON Schema compatible — OpenAPI import, MCP tool exposure, cross-language client generation
- No need to design a custom RPC wire format — irpc's is already battle-tested
- The call protocol inherits irpc's streaming and subscription patterns
- Consistency with alknet-vault's service model — both use irpc
Negative:
- alknet-call depends on irpc — if irpc has limitations or bugs, we're affected (mitigated: irpc is lightweight and we can fork if needed)
- JSON framing is not the most compact binary format — for high-throughput scenarios, a binary codec could be added later as an irpc extension
- irpc's derive macros add a compilation dependency — but this is standard for Rust RPC frameworks
- The call protocol's cross-language story depends on irpc's wire format being documented and stable (mitigated: it's length-prefixed JSON, which is inherently cross-language)
References
- Pivot proposal:
docs/research/pivot/alpn-service-architecture.md - ADR-003: Crate decomposition
- ADR-004: Auth as shared core (IdentityProvider)
- irpc reference:
docs/research/references/iroh/irpc/(see individual docs in that directory) - The previous architecture had an equivalent decision in ADR-024 (bidirectional call protocol with EventEnvelope framing), which is archived in the reference implementation at
/workspace/@alkdev/alknet-main/.