browser/openspec/changes/harden-log-artifact-channel-isolation/proposal.md

Why

Log ingest, artifact/file transfer, control heartbeat, and job ack/result delivery already exist as separate platform/run channels, but the current evidence mostly proves each channel in isolation. The next risk is starvation under load: a large artifact or file operation must not delay heartbeat, lifecycle acknowledgement, job result delivery, or durable log upload.

What Changes

• Add channel-isolation requirements that define priority, bounded payloads, retry behavior, and non-starvation guarantees across run/platform channels.
• Add run-side concurrency and queue tests proving large artifact/file work cannot block control heartbeat, job ack/result submission, or log spool upload.
• Add platform service/API tests proving artifact/log/job/control endpoints preserve independent validation, state mutation, and idempotency under interleaved requests.
• Add a local verification command set that exercises platform and run test suites plus strict OpenSpec validation.
• No breaking API changes are expected; the change hardens behavior and verification around existing channel contracts.

Capabilities

New Capabilities

• log-artifact-channel-isolation: Defines cross-channel non-starvation, bounded-transfer, durable-retry, and verification guarantees for run/platform control, job, log, artifact, and file operations.

Modified Capabilities

• None.

Impact

• Affected roots: run/ and platform/.
• Affected areas: run worker scheduling, platform client calls, log spool retry, artifact/file queue retry, platform run-facing APIs, service tests, API tests, and protocol documentation.
• Validation impact: requires focused run/platform concurrency tests, existing package tests, scripts/check-structure.sh, and openspec validate harden-log-artifact-channel-isolation --strict.