Add ADR-026 (vault key model — HD derivation) recording the foundational HD-derivation decision, 74' coin type reservation, SLIP-0010/Ed25519 default, secp256k1 feature-gating, and AES-256-GCM cipher choice. These were previously inline rationale with no ADR (W9). Extend ADR-018 with an explicit EncryptedData wire format lock — fields, encoding, and semantics are frozen; no removal without a format-version migration (W10). Resolve the remaining guard clauses and spec decisions: - W2: Capabilities must be immutable after construction (no interior mutability). Makes the Arc vs deep-copy clone semantics genuinely two-way. - W5: Published to_* specs are compatibility contracts — best-effort mappings are two-way before first publication, one-way after. Version generated specs. - W6: Salt field clarification — v2 salt is permanently unused; a future KDF is a different derivation family, not a version-indexed path; the field saves a wire-format change only. - W7: unlock_new returns Zeroizing<String> — the mnemonic is the root of trust and must not linger in freed memory. - W17: OQ-09 WASM — server-side dispatch door is honestly closed (Connection is concrete, tokio-bound), not implicitly preserved. - W18: OQ-10 git — composability fork (raw smart protocol vs call-protocol projection) is a separate decision from ERC721 scope. - W20: from_openapi must prefix imported error codes (HTTP_404) to avoid collision with protocol-level codes (NOT_FOUND). Normative rule, not naming convention. - W21: ScopedOperationEnv field is private — construction via new()/ empty(), query via allows(). Makes the future subgraph refactor non-breaking. - C13: Connection::set_identity — the endpoint does not read identity() after handle() returns (Connection is moved into the spawned task). Observability is handler-side logging. Simplest honest answer. - W1: OperationAdapter trait is async, returns Vec<HandlerRegistration>. from_call requires async discovery; ADR-022 changed the return type. - W11: CompositionAuthority::as_identity() defined — constructs a synthetic Identity (label as id, scopes, resources) not resolvable via IdentityProvider. Second Identity construction path, acknowledged. - W14: SecretKey is iroh::SecretKey (Ed25519) — consistent with the endpoint's iroh dependency. - W19: Grandchild abort propagation is inherit-by-default (option a) — invoke() with no explicit policy inherits parent's policy. ContinueRunning auto-propagates to grandchildren unless explicitly overridden.
status, last_updated
| status | last_updated |
|---|---|
| draft | 2026-06-22-22 |
alknet-call
Structured RPC over QUIC: operations, request/response, streaming subscriptions, and service discovery. Implements ProtocolHandler on ALPN alknet/call.
Documents
| Document | Status | Description |
|---|---|---|
| call-protocol.md | draft | CallAdapter, EventEnvelope framing, stream model, PendingRequestMap, bidirectional calls |
| operation-registry.md | draft | OperationSpec, Handler, OperationRegistry, AccessControl, service discovery, irpc integration |
Applicable ADRs
| ADR | Title | Relevance |
|---|---|---|
| 001 | ALPN-Based Protocol Dispatch | CallAdapter registers on ALPN alknet/call |
| 002 | ProtocolHandler Trait | CallAdapter implements ProtocolHandler |
| 003 | Crate Decomposition | alknet-call depends on alknet-core and irpc |
| 013 | Rust as Canonical Implementation Language | Adapter traits defined in Rust; TS is reference/browser adaptation |
| 004 | Auth as Shared Core | AuthContext passed to call handlers |
| 005 | irpc as Call Protocol Foundation | irpc provides framing and service dispatch |
| 006 | ALPN String Convention | alknet/call ALPN, one ALPN per connection |
| 007 | BiStream Type Definition | CallAdapter receives Connection, not BiStream |
| 008 | Vault Integration Point | Vault accessed at assembly layer, not on the wire |
| 010 | ALPN Router and Endpoint | Static handler registration |
| 012 | Call Protocol Stream Model | Bidirectional streams, EventEnvelope, ID-based correlation |
| 014 | Secret Material Flow and Capability Injection | Call protocol carries no secret material; capabilities injected at assembly layer |
| 015 | Privilege Model and Authority Context | internal = authority switch not ACL skip; External/Internal visibility; handler identity + scoped env |
| 016 | Abort Cascade for Nested Calls | call.aborted cascades to descendants; default abort-dependents, continue-running opt-in |
| 017 | Call Protocol Client and Adapter Contract | CallClient opens connections; from_call imports remote ops; connection direction independent of call direction |
| 022 | Handler Registration, Provenance, and Composition Authority | Registration bundle carries provenance, composition authority, scoped env, capabilities |
| 023 | Operation Error Schemas | Operations declare domain errors; call.error carries typed details; adapter fidelity |
| 024 | Operation Registry Layering | Curated (static) + session/connection overlays (dynamic); OperationEnv as trait-object integration point; OperationContext.env split into scoped_env (data) and env (dispatch trait) |
Relevant Open Questions
| OQ | Title | Status | Relevance |
|---|---|---|---|
| OQ-07 | Call protocol scope within a connection | resolved (ADR-012) | Stream model, multiplexing, scope |
| OQ-13 | Operation path format and routing scope | resolved | /{service}/{op} is the correct design; remote dispatch is a separate layer |
| OQ-14 | Batch operation semantics | resolved | Correlated call.requested events is the correct protocol design |
| OQ-16 | Safe vault operations for call protocol exposure | resolved (ADR-014) | None exposed for now |
| OQ-19 | Session-scoped operation registries | resolved | Agent-written operations overlaid on curated registry via OperationEnv trait layering. Protocol doesn't need changes; OperationEnv must remain a trait. Generalized by ADR-024 to cover connection-scoped overlays. |
Key Design Principles
- One connection, full access: An
alknet/callconnection gives access to the entire operation registry — calls, subscriptions, batch, schema. - Protocol is symmetric: Both sides can initiate calls. The server calling a client uses the same EventEnvelope format and correlation.
- Stream-agnostic correlation: PendingRequestMap correlates by request ID, not by stream. The protocol works with any stream arrangement.
- Operation registry is layered: The curated layer (
Localprovenance) is static — registered at startup by the CLI binary, immutable for the process lifetime. Session (Session) and imported (FromCalletc.) ops are dynamic overlays at their respective scopes (per-session, per-connection). The registry supports JSON Schema discovery. See ADR-024. - irpc is one dispatch backend: Local operations dispatch directly. irpc service calls (in-process, type-safe) are internal. The call protocol is the external interface.
- Local dispatch only: The operation registry dispatches to local handlers. Remote dispatch (federation, head/worker routing) would be a separate mechanism at a different layer, not a modification to alknet-call's path format.
- No secret material on the wire: The call protocol carries no private keys, API keys, mnemonics, or decrypted credentials. Handlers receive outbound credentials through
OperationContext.capabilities, injected at the assembly layer. See ADR-014. - Abort cascades to descendants:
call.abortedfor a parent request cascades to all non-terminal descendants. Defaultabort-dependents;continue-runningopt-in. See ADR-016. - Internal calls switch authority context, not skip ACL: The
internalflag marks composition-originated calls. ACL runs against the handler's composition authority, not the caller's and not as a blanket skip. Operations have External/Internal visibility. Scoped composition env bounds reachability. See ADR-015, ADR-022. - Provenance determines composition capability: Only
LocalandSessionops can compose. Leaves (FromOpenAPI,FromMCP,FromCall) are forwarding stubs — they don't get composition authority or a scoped env. The assembly layer is the sole grantor of composition authority. See ADR-022.