[world-vercel] Use v3 stream endpoint (supports transparent reconnect on timeout)#2424
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Point the world-vercel live-stream reader at the v3 stream endpoint. On a max-duration timeout (or mid-stream connection drop) the v3 server errors the response body rather than closing it cleanly, which is what lets the reconnecting reader resume from the next chunk instead of treating the timeout as end-of-stream. Writes, completion, and snapshot reads stay on v2. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
🦋 Changeset detectedLatest commit: 2fb4892 The changes in this PR will be included in the next version bump. This PR includes changesets to release 17 packages
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VaguelySerious
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Jun 15, 2026
Signed-off-by: Peter Wielander <mittgfu@gmail.com>
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karthikscale3
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Jun 22, 2026
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Reviewed for blockers and regressions. I did not find any issues.
| // (chunks/info/list) stay on v2. | ||
| function getStreamReadUrl(name: string, runId: string, httpConfig: HttpConfig) { | ||
| return new URL( | ||
| `${httpConfig.baseUrl}/v3/runs/${encodeURIComponent(runId)}/stream/${encodeURIComponent(name)}` |
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AI Review: Verified that only live stream reads move to the v3 endpoint while writes, close, and snapshot reads stay on v2, preserving existing write semantics while enabling reconnect-on-timeout behavior.
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Backport to To resolve manually, push a backport branch and open a PR against git fetch origin stable
git checkout -b backport/pr-2424-to-stable origin/stable
git cherry-pick -S d476d7aaf6fd58d5d7241d2152fb7a705a27c4e4 # -S signs the commit
# Fix conflicts, then:
git add -A
git cherry-pick --continue
git push -u origin backport/pr-2424-to-stable
gh pr create --base stable --head backport/pr-2424-to-stable \
--title "Backport #2424: <original PR title>" \
--body "Manual backport of #2424 (cherry-pick d476d7aaf6fd) to \`stable\`." |
This was referenced Jun 23, 2026
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Needs V3 stream API to be live on the server first.
Point the
world-vercellive-stream reader (world.streams.get, used byrun.getReadable()) at the v3 stream endpoint instead of v2. Writes, stream completion, and snapshot reads (chunks/info/list) stay on v2 — only the long-lived live read is affected.Why
On the v3 endpoint the server errors the response body on a max-duration timeout (or a mid-stream connection drop) rather than closing it cleanly. That thrown error is exactly what the reconnecting reader (
createReconnectingFramedStream) needs to resume from the next chunk viastartIndex. On v2 the server closes cleanly, which the reader treats as end-of-stream — so today long-lived streams silently truncate at the server's 2-minute limit. This change makes object-stream reads (e.g. the AI chatUIMessageChunkstream) transparently survive the timeout.The reconnecting reader already shipped (#2318 on
main, #1847 onstable); it's been inert because the server never errored on timeout. This flips it on.