delegation

delegation

Research orchestrator that fans a single request out to three peer runtimes via agent.delegate, demultiplexes their event streams, tolerates per-peer failure.

Before ARCP

Each peer agent is reached over its own bespoke HTTP/SSE endpoint. The orchestrator stands up three separate websockets, parses three different event formats, and writes three retry loops. Trace context is "added later" and never quite makes it across the seam.

With ARCP

$traceId = TraceId::random();
foreach (PEERS as $peer) {
    $job = delegate($client, $peer, $request, $traceId);
    if ($job->jobId !== null) {
        $mux->register($job->jobId);
    }
    $jobs[] = $job;
}

$completed = array_map(fn ($j) => $mux->collect($j), $jobs);

One transport, one envelope shape, one trace. Per-peer failure is a typed job.failed envelope, not a 502 with a stack trace.

ARCP primitives

• agent.delegate + trace_id propagation — RFC §14, §17.1.
• Job lifecycle (accepted → terminal) — §10.2.
• Stream/event multiplexing across job_id — §6.4.

File tour

• main.php — fan-out / gather / synthesize. JobMux is here.
• synth.php — synthesize() final-pass LLM stub.

Variations

• Bound the fan-out by capability (e.g. only peers advertising arcpx.research.web.v1).
• Return artifact refs from peers (job.completed.result_ref) instead of inline results when payloads cross the inline budget (§16).
• Cancel slowest peer once N succeed via cancel (see cancellation).