Backport #2998: fix(world-vercel): append caller User-Agent products instead of discarding them

[github-actions]

Automated backport of #2998 to stable (backport job run).

AI recommendation: This is a self-contained bug fix to @workflow/world-vercel's getHeaders, which exists on stable with the same defect (headers.set('User-Agent', getUserAgent()) at packages/world-vercel/src/utils.ts:343 discards caller-provided User-Agent tokens). The change is small, includes a test and docs update, and does not depend on any main-only APIs.

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

[changeset-bot]

🦋 Changeset detected

Latest commit: 351a7ed

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

This PR includes changesets to release 17 packages

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

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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 (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jul 20, 2026 11:27pm
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jul 20, 2026 11:27pm
example-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-astro-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-express-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-fastify-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-hono-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-nestjs-workflow	Error		Jul 20, 2026 11:27pm
workbench-nitro-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-nuxt-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-sveltekit-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-tanstack-start-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workbench-vite-workflow	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workflow-docs	Ready	Preview, Comment, Open in v0	Jul 20, 2026 11:27pm
workflow-swc-playground	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workflow-tarballs	Ready	Preview, Comment	Jul 20, 2026 11:27pm
workflow-web	Ready	Preview, Comment	Jul 20, 2026 11:27pm

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	1077	0	78	1155
✅ 💻 Local Development	1174	0	86	1260
✅ 📦 Local Production	1174	0	86	1260
✅ 🐘 Local Postgres	1174	0	86	1260
✅ 🪟 Windows	105	0	0	105
❌ 🌍 Community Worlds	82	102	9	193
✅ 📋 Other	594	0	36	630
Total	5380	102	381	5863

❌ Failed Tests

🌍 Community Worlds (102 failed)

redis (19 failed):

• hookWorkflow | wrun_01KY0ZQNZC0D0S6TMH9N36QZ9F
• hookWorkflow is not resumable via public webhook endpoint | wrun_01KY0ZQZAAAV0QG8R9DYJS33WN
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01KY0ZR8H7ZW9R6B88VVZC3584
• sleepingWorkflow | wrun_01KY0ZSADA73Y4KYRTRDKS75QC
• 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
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01KY101C5DRZPNBWX0MHR5BBFE
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01KY101SNQTMCBVXXTNVSWA0ZJ
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01KY1021MSNWBXDYD0JGG1A1V3
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01KY102FSHC8224A1CJCCPA461
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01KY103AVA10RRCSQDN1BZ5RQM
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01KY103F9GW1SXXQPCXXFQ3X0X
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01KY103NVYZ98P2HP2Y6NTCPSX
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01KY103V8AWMZJG43RMT77EYQS
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01KY1044W1RJCPPRGBS205TVN4
• pages router sleepingWorkflow via pages router
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01KY109ZNJHB659T7FPP1EBXMM

turso (83 failed):

• addTenWorkflow | wrun_01KY0ZPN08YERDEH2P3JWX1YVW
• addTenWorkflow | wrun_01KY0ZPN08YERDEH2P3JWX1YVW
• deploymentId: 'latest' is a no-op in non-Vercel worlds
• wellKnownAgentWorkflow (.well-known/agent) | wrun_01KY0ZPYCE72WY7NN5H4QXGZ97
• should work with react rendering in step
• promiseAllWorkflow | wrun_01KY0ZPWJVR9X8FTH443GWYB1N
• promiseRaceWorkflow | wrun_01KY0ZQ19A5PFCBC93QAJZ6301
• promiseAnyWorkflow | wrun_01KY0ZQ3RZH7VAXMH87X3QYXJW
• importedStepOnlyWorkflow | wrun_01KY0ZQCA7YN093NDFJWFGBNDH
• readableStreamWorkflow | wrun_01KY0ZQ6B50E6GCZ4W6TGE956D
• hookWorkflow | wrun_01KY0ZQNZC0D0S6TMH9N36QZ9F
• hookWorkflow is not resumable via public webhook endpoint | wrun_01KY0ZQZAAAV0QG8R9DYJS33WN
• webhookWorkflow | wrun_01KY0ZR3CBMSG3DRPCVBS7WK74
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01KY0ZR8H7ZW9R6B88VVZC3584
• sleepingWorkflow | wrun_01KY0ZSADA73Y4KYRTRDKS75QC
• parallelSleepWorkflow | wrun_01KY0ZSTAQQ9XR9CYH3HG53V7S
• sleepWinsRaceWorkflow | wrun_01KY0ZSY1EKJ0YJ0PB5VY2F2Y2
• stepWinsRaceWorkflow | wrun_01KY0ZT1W6SY9QY45BWKXV59FA
• nullByteWorkflow | wrun_01KY0ZT5MF0VWB1NY3M8PEMA8K
• workflowAndStepMetadataWorkflow | wrun_01KY0ZT7X9JY9HT94Y4MBTCG5F
• 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_01KY0ZWKP4RPHJ5QK4AB1JWDZ9
• writableForwardedFromWorkflowWorkflow | wrun_01KY0ZX1V64D2PRV875P9J0F90
• writableForwardedFromStepWorkflow | wrun_01KY0ZX6BJ66C0SG319ENXTEEC
• fetchWorkflow | wrun_01KY0ZX9WASJEW7YZ0FRPDVC25
• promiseRaceStressTestWorkflow | wrun_01KY0ZXDKRX3Z9Q1DK582TSC3K
• 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 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_01KY100Z2ER6AS6HZJEGSF10RP
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01KY101C5DRZPNBWX0MHR5BBFE
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01KY101SNQTMCBVXXTNVSWA0ZJ
• 'hookGetConflictWithPriorStepWorkflow' - hook.getConflict() does not block step execution | wrun_01KY101W9CGY6VTNCA4F21MMBZ
• 'hookGetConflictWithParallelStepWorkfl…' - hook.getConflict() does not block step execution | wrun_01KY101Z2BKHMQCJ7NG6Z69NKB
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01KY1021MSNWBXDYD0JGG1A1V3
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01KY102FSHC8224A1CJCCPA461
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01KY103AVA10RRCSQDN1BZ5RQM
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01KY103F9GW1SXXQPCXXFQ3X0X
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01KY103NVYZ98P2HP2Y6NTCPSX
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01KY103V8AWMZJG43RMT77EYQS
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01KY1044W1RJCPPRGBS205TVN4
• hookDisposeTestWorkflow - hook token reuse after explicit disposal while workflow still running | wrun_01KY104BCR06H9VF6Z8ESPVXG9
• stepFunctionPassingWorkflow - step function references can be passed as arguments (without closure vars) | wrun_01KY104VV6Y3KTM6G94M06Q66X
• stepFunctionWithClosureWorkflow - step function with closure variables passed as argument | wrun_01KY1055KTTBKYVKZMW4488Z8A
• closureVariableWorkflow - nested step functions with closure variables | wrun_01KY105BH4SK8RS07G3F88491Q
• spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step | wrun_01KY105DV3VFHXJWR1QGANW1XC
• 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_01KY105YQAEM1V7D2KQ0C2123T
• Calculator.calculate - static workflow method using static step methods from another class | wrun_01KY1064Z3NBGNMA1H67CP6JWC
• AllInOneService.processNumber - static workflow method using sibling static step methods | wrun_01KY106AWGYZ8KW806M0HRQZ9E
• ChainableService.processWithThis - static step methods using this to reference the class | wrun_01KY106J11ZBVPVWXY2DAE701H
• thisSerializationWorkflow - step function invoked with .call() and .apply() | wrun_01KY106S9H4EC6FCQ51JBMHXT0
• customSerializationWorkflow - custom class serialization with WORKFLOW_SERIALIZE/WORKFLOW_DESERIALIZE | wrun_01KY1070HE2FE5CW4G0TF4MG5W
• instanceMethodStepWorkflow - instance methods with "use step" directive | wrun_01KY1077V4CTN5H2V6J56NT7HF
• crossContextSerdeWorkflow - classes defined in step code are deserializable in workflow context | wrun_01KY107NEPP29SPSNZ25MAH3E1
• stepFunctionAsStartArgWorkflow - step function reference passed as start() argument | wrun_01KY107XS7Y90RDESEXE7WXBK7
• cancelRun - cancelling a running workflow | wrun_01KY10850P8MJKP4K7B7MM3AP0
• cancelRun via CLI - cancelling a running workflow | wrun_01KY108A4APXCZTN2PZVX05KNF
• 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_01KY108JC4TH8FYFZ5K0CFT9QN
• hookWithSleepFinalStepWorkflow - step only on final payload | wrun_01KY108ZKWPSHYM2S62SYH8RGD
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_01KY10996ACD3ZD03JBW24Z5KB
• sleepWithSequentialStepsWorkflow - sequential steps work with concurrent sleep (control) | wrun_01KY109KSMY6GRJ2B2540AJY9N
• importMetaUrlWorkflow - import.meta.url is available in step bundles | wrun_01KY109TVYJ440Z3NWKJ9HCFB9
• metadataFromHelperWorkflow - getWorkflowMetadata/getStepMetadata work from module-level helper (#1577) | wrun_01KY109X9AKMK72Z92YV1XYXZD
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01KY109ZNJHB659T7FPP1EBXMM

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	97	0	8
✅ example	97	0	8
✅ express	97	0	8
✅ fastify	97	0	8
✅ hono	97	0	8
✅ nextjs-turbopack	102	0	3
✅ nextjs-webpack	102	0	3
✅ nitro	97	0	8
✅ nuxt	97	0	8
✅ sveltekit	97	0	8
✅ vite	97	0	8

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	105	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	4	0	3
✅ redis-dev	4	0	3
❌ redis	67	19	0
✅ turso-dev	4	0	3
❌ turso	3	83	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	99	0	6
✅ e2e-local-dev-tanstack-start-stable	99	0	6
✅ e2e-local-postgres-nest-stable	99	0	6
✅ e2e-local-postgres-tanstack-start-stable	99	0	6
✅ e2e-local-prod-nest-stable	99	0	6
✅ e2e-local-prod-tanstack-start-stable	99	0	6

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📋 View full workflow run