Agent SDK rewind_conversation and a Sume job: find, then cancel

After rewind_conversation or a priority-now message, the MCP call is handled client-side. A submitted Sume job has its own id: find it with jobs_list.

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Agent SDK 0.3.285 stops rewind_conversation from leaving a backgrounded MCP tool call running once its starting message is removed. That governs the client's call. A Sume job already submitted has its own id, so look it up with jobs_list and decide whether to call jobs_cancel.

SDK facts are from its release notes; job tools from MCP tools and gates, read 2026-10-01. The docs do not say a client-side cancel propagates to Sume, so check rather than assume.

What did the two releases change?

0.3.285 (2026-09-29): fixed rewind_conversation leaving a backgrounded MCP tool call running after the message that started it was removed. 0.3.286 (2026-09-30): a person's "priority now" message now moves running shell commands, agents and MCP calls to the background and joins the running turn instead of stopping it.

How do I find a Sume job after a rewind?

Use the read tools; none of them need an idempotency_key.

Job tools from the Sume docs, read 2026-10-01: https://docs.sume.com/mcp/tools-and-gates
ToolKindUse after a rewind
jobs_listReadSee what is still in flight
jobs_get, jobs_statusReadCheck one job
jobs_resultReadCollect artifacts if it finished
jobs_eventsReadReview what happened
jobs_cancelWriteNeeds idempotency_key and write scope

When should I call jobs_cancel?

Only for a job you no longer want. It is a write tool, so it needs mcp:write or an API key; a read-only OAuth session gets insufficient_scope. Do not resubmit the original create just because the turn was rewound, since that would start a second paid job. Related: interrupts and running jobs.

What should I keep from the rewound turn?

The job id, and later the result. The docs advise reporting Sume public ids and media.sume.com URLs rather than pasting signed URLs, tokens or keys into chat logs.

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