feat: support Vercel AI SDK 5 Beta

[thucpn]

Flow:

• llamaindex-workflow produces events
• llamaindex-server transform events to SSE
• vercel/ai computes events to parts (text, weather, sources,...)
• chat-ui renders parts (texts -> multiple markdown blocks, other parts -> annotation blocks)

Breaking changes:

• Backend:
  • need data-* prefix for annotations type. eg: 'data-weather'
  • use standard Server-Sent Events
• Chat-UI contract:
  • reload and append are removed (use regenerate and sendMessage instead)
  • message.content is removed (use message.parts.filter(p => p.type === 'text') instead)
  • message.annotations is removed (use `message.parts.filter(p => p.type !== 'text') instead)
• Simplify EventPart and FilePart:
  • removed EventAnnotations (type = "events") and AgentEventAnnotations (type = "agent-events"). Instead, I create EventPart (type = "event) that leverage new "part id" feature.
  • removed ImageAnnotations (type = "image") and DocumentFileAnnotations (type = "document-file"). Instead, I create FilePart (type = "file"), it will cover display all file types

Tasks:

• update ChatHandler contract to work with Vercel AI SDK 5
• update for ai/rsc
• update useChatWorkfow
• update app/web
• update registry
• update nextjs example
• update @llamaindex/server
• update fastapi example
• retest llamadeploy example
• update document

[changeset-bot]

🦋 Changeset detected

Latest commit: 7ac96ac

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

This PR includes changesets to release 6 packages

Name	Type
@llamaindex/chat-ui	Minor
@llamaindex/server	Minor
llamaindex-server-examples	Patch
web	Patch
@llamaindex/chat-ui-docs	Patch
@llamaindex/dynamic-ui	Major

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Project	Deployment	Preview	Comments	Updated (UTC)
chat-ui-web	✅ Ready	Preview	💬 Add feedback	Aug 12, 2025 8:41am