Backport #4326: [core] Fix Run.returnValue retrying its accessor step for a terminal run

[github-actions]

Automated backport of #4326 to stable (backport job run).

AI recommendation: This is a correctness bug fix: WorkflowRunFailedError and WorkflowRunCancelledError were treated as transient, so await run.returnValue on an already-terminal run burned its full retry budget re-reading an immutable record and ultimately surfaced a retry-exhaustion FatalError wrapper instead of the documented error class. Both classes and the FatalError.is() own-property gate already exist on stable (verified in packages/errors/src/index.ts), so the defect affects the maintenance line. The commit is fix + tests + doc corrections only, with no new API surface (the two changed v5 error doc pages don't exist on stable, so that part may simply be dropped during the cherry-pick).

Merge conflicts were resolved by AI (opencode with anthropic/claude-opus-5). Please review the conflict resolution carefully before merging.

[changeset-bot]

🦋 Changeset detected

Latest commit: 7d226ff

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 20 packages

Name	Type
@workflow/errors	Patch
@workflow/core	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/web	Patch
workflow	Patch
@workflow/world-local	Patch
@workflow/world-postgres	Patch
@workflow/world-vercel	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/vitest	Patch
@workflow/web-shared	Patch
@workflow/world-testing	Patch
@workflow/astro	Patch
@workflow/nest	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
@workflow/vite	Patch
@workflow/nuxt	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[vercel]

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Project	Deployment	Actions	Updated
example-nextjs-workflow-turbopack	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
example-nextjs-workflow-webpack	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
example-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-astro-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-express-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-fastify-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-hono-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-nestjs-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-nitro-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-nuxt-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-python-workflow	Error	v0	Sep 24, 2026 12:23am UTC
workbench-sveltekit-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-tanstack-start-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workbench-vite-workflow	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workflow-docs	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workflow-swc-playground	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workflow-tarballs	Ready	Preview, v0	Sep 24, 2026 12:23am UTC
workflow-web	Ready	Preview, v0	Sep 24, 2026 12:23am UTC

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	1099	0	78	1177
✅ 💻 Local Development	1198	0	86	1284
✅ 📦 Local Production	1198	0	86	1284
✅ 🐘 Local Postgres	1198	0	86	1284
✅ 🪟 Windows	107	0	0	107
❌ 🌍 Community Worlds	82	106	9	197
✅ 📋 Other	606	0	36	642
Total	5488	106	381	5975

❌ Failed Tests

🌍 Community Worlds (106 failed)

redis (21 failed):

• hookWorkflow | wrun_01M3ACSJZ6S4SNMV9KTZGZA9TC
• hookWorkflow is not resumable via public webhook endpoint | wrun_01M3ACSTG3FRD6X3GQGR8H15VB
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01M3ACT3RRNH1NYAKYDHV3FP2S
• sleepingWorkflow | wrun_01M3ACV28KWT5Y8WBC6Q6E94DS
• outputStreamWorkflow negative startIndex (reads from end)
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns correct index after stream completes
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns -1 before any chunks are written
• outputStreamWorkflow - getTailIndex and getStreamChunks getStreamChunks returns same content as reading the stream
• error handling serialization failures step-argument serialization failure is catchable in workflow code
• error handling serialization failures uncaught step-argument serialization failure fails the run as USER_ERROR without redelivery retries
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01M3AD2M70AHQ88EEADBM481SG
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01M3AD2YGNMYGFCCV39TBE0SKJ
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01M3AD35BA4QSBJVFRG2TJPC8A
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01M3AD3JV1A9FZ0207R3EDJYNG
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01M3AD4C3X13F8ZTKDWV2SZARN
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01M3AD4F6TBPP8PXM3NGVS96EJ
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01M3AD4KZ90EFVGB0T3VX3PMVG
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01M3AD4S8KY68EKWTK07PZ0B6B
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01M3AD516860KCN6ZV079XK095
• pages router sleepingWorkflow via pages router
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01M3AD9T7YP17ZFWFK0CSV0SRV

turso (85 failed):

• addTenWorkflow | wrun_01M3ACRFBNSNEYP4HMCCVKTFXJ
• addTenWorkflow | wrun_01M3ACRFBNSNEYP4HMCCVKTFXJ
• deploymentId: 'latest' is a no-op in non-Vercel worlds
• wellKnownAgentWorkflow (.well-known/agent) | wrun_01M3ACRWK5410BJQ10RA5FDXZ2
• should work with react rendering in step
• promiseAllWorkflow | wrun_01M3ACRPGC71X8JFTFFE91DSWP
• promiseRaceWorkflow | wrun_01M3ACRW2BAK5X56GZBM1GFBCC
• promiseAnyWorkflow | wrun_01M3ACS0F6N9WRG1S4A4G055MN
• importedStepOnlyWorkflow | wrun_01M3ACS70FG66P0P65PPN0PBX0
• readableStreamWorkflow | wrun_01M3ACS2HYMS187C4KT2PMFDN6
• hookWorkflow | wrun_01M3ACSJZ6S4SNMV9KTZGZA9TC
• hookWorkflow is not resumable via public webhook endpoint | wrun_01M3ACSTG3FRD6X3GQGR8H15VB
• webhookWorkflow | wrun_01M3ACSYDBW45T6KA7ET71V41T
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01M3ACT3RRNH1NYAKYDHV3FP2S
• sleepingWorkflow | wrun_01M3ACV28KWT5Y8WBC6Q6E94DS
• parallelSleepWorkflow | wrun_01M3ACVHJJX4JYWJXQ528ZY2HV
• sleepWinsRaceWorkflow | wrun_01M3ACVMYPQ8Z9FBNADVSQ0C57
• stepWinsRaceWorkflow | wrun_01M3ACVR61XP6JR1G02HQME06D
• nullByteWorkflow | wrun_01M3ACVVAWQEGRW7AK5GBZWQM6
• workflowAndStepMetadataWorkflow | wrun_01M3ACVXF14TKJRF1DAJY4JY1S
• outputStreamWorkflow no startIndex (reads all chunks)
• outputStreamWorkflow positive startIndex (skips first chunk)
• outputStreamWorkflow negative startIndex (reads from end)
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns correct index after stream completes
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns -1 before any chunks are written
• outputStreamWorkflow - getTailIndex and getStreamChunks getStreamChunks returns same content as reading the stream
• outputStreamInsideStepWorkflow - getWritable() called inside step functions | wrun_01M3ACY6PM3TN09SWY4FR0PYAB
• writableForwardedFromWorkflowWorkflow | wrun_01M3ACYJXHWMT95JSA7KZXSZDA
• writableForwardedFromStepWorkflow | wrun_01M3ACYPBKWH788V722CRW1C7W
• fetchWorkflow | wrun_01M3ACYRSYY8FDAT0NJP5EXJ4Z
• promiseRaceStressTestWorkflow | wrun_01M3ACYW299GEK51K3BW4MVP2K
• error handling error propagation workflow errors nested function calls preserve message and stack trace
• error handling error propagation workflow errors cross-file imports preserve message and stack trace
• error handling error propagation step errors basic step error preserves message and stack trace
• error handling error propagation step errors cross-file step error preserves message and function names in stack
• error handling retry behavior regular Error retries until success
• error handling retry behavior FatalError fails immediately without retries
• error handling retry behavior RetryableError respects custom retryAfter delay
• error handling retry behavior maxRetries=0 disables retries
• error handling catchability FatalError can be caught and detected with FatalError.is()
• error handling serialization failures step-argument serialization failure is catchable in workflow code
• error handling serialization failures uncaught step-argument serialization failure fails the run as USER_ERROR without redelivery retries
• error handling not registered WorkflowNotRegisteredError fails the run when workflow does not exist
• error handling not registered StepNotRegisteredError fails the step but workflow can catch it
• error handling not registered StepNotRegisteredError fails the run when not caught in workflow
• hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_01M3AD2ABAPA0NDD5FSZBP39ET
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01M3AD2M70AHQ88EEADBM481SG
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01M3AD2YGNMYGFCCV39TBE0SKJ
• 'hookGetConflictWithPriorStepWorkflow' - hook.getConflict() does not block step execution | wrun_01M3AD30SAXTX3YJFQQAFS41RN
• 'hookGetConflictWithParallelStepWorkfl…' - hook.getConflict() does not block step execution | wrun_01M3AD333FQ61KY1P02T62N9CK
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01M3AD35BA4QSBJVFRG2TJPC8A
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01M3AD3JV1A9FZ0207R3EDJYNG
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01M3AD4C3X13F8ZTKDWV2SZARN
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01M3AD4F6TBPP8PXM3NGVS96EJ
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01M3AD4KZ90EFVGB0T3VX3PMVG
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01M3AD4S8KY68EKWTK07PZ0B6B
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01M3AD516860KCN6ZV079XK095
• hookDisposeTestWorkflow - hook token reuse after explicit disposal while workflow still running | wrun_01M3AD57ST4ZGPSA03SME237PX
• stepFunctionPassingWorkflow - step function references can be passed as arguments (without closure vars) | wrun_01M3AD5N0SCK8QPP7S73YQWR8M
• stepFunctionWithClosureWorkflow - step function with closure variables passed as argument | wrun_01M3AD5WKB8GN15KHEK3P3JB67
• closureVariableWorkflow - nested step functions with closure variables | wrun_01M3AD61BQ47K06FP6D8352NTE
• spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step | wrun_01M3AD63FYM7T9J0MEXEDA8YTQ
• health check (queue-based) - workflow and step endpoints respond to health check messages
• health check (CLI) - workflow health command reports healthy endpoints
• pathsAliasWorkflow - TypeScript path aliases resolve correctly | wrun_01M3AD6GX4JVCFZ2QJ47TZ3SAB
• Calculator.calculate - static workflow method using static step methods from another class | wrun_01M3AD6NQKHRRD8PDGP1WEE4M5
• AllInOneService.processNumber - static workflow method using sibling static step methods | wrun_01M3AD6VR303SPY03W8Q607SSX
• ChainableService.processWithThis - static step methods using this to reference the class | wrun_01M3AD70HHGET9EGBAQNFRVKZ4
• thisSerializationWorkflow - step function invoked with .call() and .apply() | wrun_01M3AD75BTAQSAM4TCJF4MTNVC
• customSerializationWorkflow - custom class serialization with WORKFLOW_SERIALIZE/WORKFLOW_DESERIALIZE | wrun_01M3AD7BFGKPRWMA9TM0J5WAQZ
• instanceMethodStepWorkflow - instance methods with "use step" directive | wrun_01M3AD7HF0CZN1BTWAK6X6EC50
• crossContextSerdeWorkflow - classes defined in step code are deserializable in workflow context | wrun_01M3AD7WC3YADMSEBT98VSJ191
• stepFunctionAsStartArgWorkflow - step function reference passed as start() argument | wrun_01M3AD83G4PFQKYD78HB83G15S
• cancelRun - cancelling a running workflow | wrun_01M3AD89BAMHQXG4HCKX8MM23F
• cancelRun via CLI - cancelling a running workflow | wrun_01M3AD8DEG4ZPAP31BP4PGDM3N
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router
• hookWithSleepWorkflow - hook payloads delivered correctly with concurrent sleep | wrun_01M3AD8KSS44KDGZR0G8HWE9B4
• hookWithSleepFinalStepWorkflow - step only on final payload | wrun_01M3AD8Y5WRS3GBEFEYBA9PYK8
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_01M3AD962XRE0EZSHJ052KKWSV
• sleepWithSequentialStepsWorkflow - sequential steps work with concurrent sleep (control) | wrun_01M3AD9G9FQMMJK4XP4D77ZHBX
• importMetaUrlWorkflow - import.meta.url is available in step bundles | wrun_01M3AD9P2NATESWF3FZRFESKB5
• metadataFromHelperWorkflow - getWorkflowMetadata/getStepMetadata work from module-level helper (#1577) | wrun_01M3AD9R5M4WVFHHXKRH11WQDK
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01M3AD9T7YP17ZFWFK0CSV0SRV

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	99	0	8
✅ example	99	0	8
✅ express	99	0	8
✅ fastify	99	0	8
✅ hono	99	0	8
✅ nextjs-turbopack	104	0	3
✅ nextjs-webpack	104	0	3
✅ nitro	99	0	8
✅ nuxt	99	0	8
✅ sveltekit	99	0	8
✅ vite	99	0	8

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	101	0	6
✅ express-stable	101	0	6
✅ fastify-stable	101	0	6
✅ hono-stable	101	0	6
✅ nextjs-turbopack-canary	88	0	19
✅ nextjs-turbopack-stable	107	0	0
✅ nextjs-webpack-canary	88	0	19
✅ nextjs-webpack-stable	107	0	0
✅ nitro-stable	101	0	6
✅ nuxt-stable	101	0	6
✅ sveltekit-stable	101	0	6
✅ vite-stable	101	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	101	0	6
✅ express-stable	101	0	6
✅ fastify-stable	101	0	6
✅ hono-stable	101	0	6
✅ nextjs-turbopack-canary	88	0	19
✅ nextjs-turbopack-stable	107	0	0
✅ nextjs-webpack-canary	88	0	19
✅ nextjs-webpack-stable	107	0	0
✅ nitro-stable	101	0	6
✅ nuxt-stable	101	0	6
✅ sveltekit-stable	101	0	6
✅ vite-stable	101	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	101	0	6
✅ express-stable	101	0	6
✅ fastify-stable	101	0	6
✅ hono-stable	101	0	6
✅ nextjs-turbopack-canary	88	0	19
✅ nextjs-turbopack-stable	107	0	0
✅ nextjs-webpack-canary	88	0	19
✅ nextjs-webpack-stable	107	0	0
✅ nitro-stable	101	0	6
✅ nuxt-stable	101	0	6
✅ sveltekit-stable	101	0	6
✅ vite-stable	101	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	107	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	4	0	3
✅ redis-dev	4	0	3
❌ redis	67	21	0
✅ turso-dev	4	0	3
❌ turso	3	85	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	101	0	6
✅ e2e-local-dev-tanstack-start-stable	101	0	6
✅ e2e-local-postgres-nest-stable	101	0	6
✅ e2e-local-postgres-tanstack-start-stable	101	0	6
✅ e2e-local-prod-nest-stable	101	0	6
✅ e2e-local-prod-tanstack-start-stable	101	0	6

---

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