Swift 6 reference implementation of the Agent Runtime Control Protocol (RFC 0001 v2). Wire version: 1.0. SDK version: 0.1.0.
v0.1.0 — protocol fundamentals across the seven gated phases:
- ✅ Envelope, ids (ULID), errors, extension registry, SQLite event log
- ✅ Four-step handshake (RFC §8.1) with
bearer,signed_jwt,noneschemes - ✅ Capability negotiation (RFC §7)
- ✅ Durable jobs with state machine, heartbeats, cooperative cancellation, interrupts
- ✅ Multi-kind streams (text, event, log, thought, metric, base64 binary) + backpressure
- ✅ Human-in-the-loop primitives with first-response-wins resolution and default fallback
- ✅ Permission challenges + lease lifecycle (grant, refresh, revoke, expire sweep)
- ✅ Subscriptions with filter, backfill,
subscription.backfill_completeboundary - ✅ Inline-base64 artifacts with retention sweep
- ✅ Resume by
after_message_id - ✅ Transports:
MemoryTransport(tests),StdioTransport(NDJSON),WebSocketTransport(client)
Out of scope for v0.1 (see CONFORMANCE.md): mTLS / OAuth2 auth,
sidecar binary stream frames, scheduled jobs, multi-agent delegation/handoff,
trust elevation, checkpoint-based resume, full WebSocket server (the client
transport works; server is partial because WebSocketKit.WebSocket's
server-side initializer is internal — full server lands in v0.2).
- Swift 6.0 toolchain or later (validated against 6.3.1)
- macOS 14+ or Linux (Ubuntu 22.04+ tested)
git clone <this repo>
cd swift-sdk
swift run sample-01-minimal-sessionExpected output:
Sample 01 — minimal session (wire 1.0)
session opened: sess_01...
pong nonce: hello
session closed
The other five samples — sample-02-tool-invoke-progress,
sample-03-human-input-request, sample-04-permission-challenge,
sample-05-observer-subscription, sample-06-relay-human-in-the-loop — each
demonstrate a distinct ARCP surface end-to-end via the in-memory transport.
swift run arcp serve # accept one ARCP session over stdio
swift run arcp send <tool> --args '{"k":"v"}'
swift run arcp tail # subscribe and print events
swift run arcp replay <db> <session>The seven phases of v0.1 each pass these five commands at exit code 0:
swift package plugin --allow-writing-to-package-directory format-source-code
swift package plugin lint-source-code -- --strict
swift build -c release -Xswiftc -warnings-as-errors
swift test --parallel --enable-code-coverage
swift package generate-documentation --target ARCP
State diagrams for sessions, jobs, streams, subscriptions, and leases live in
PLAN.md §6.
PLAN.md §5 maps every in-scope wire message type to its
MessageType enum case and payload struct. Out-of-scope types decode as
.unknown(typeName:payload:) and are rejected per RFC §21.3 with UNIMPLEMENTED
when a non-optional sender expects them.
Apache License 2.0 — see LICENSE in this directory.