TanStackChatMessage.content uses any[] for multimodal so
messages are directly passable to any adapter without casts.
Add env.d.ts with vite/client types for CSS imports.
- Fix convertInputToTanStackAI silently dropping multimodal
content (images, audio, video, documents) by converting
AG-UI content parts to TanStack AI ContentPart format
- Switch react-router example from Hono server to a React
Router resource route using createCopilotRuntimeHandler
- Both agents now use BuiltInAgent factory pattern
- Remove hono/react-router-hono-server deps from example
- Close TOCTOU window: set abortController synchronously before Observable
creation in classic run(), matching factory run() pattern (M3)
- Add concurrent run guard to classic run() (C1)
- Add threadId/runId to RUN_ERROR events in classic mode (I2)
- Check both 'output' and 'result' property names in classic tool-result (C2/M2)
- Add try/catch around JSON.stringify in classic tool-result (I4/M2)
- Add undefined guards before emitting state snapshot/delta events (I3)
- Guard assignToolsToAgents against factory-mode agent configs (M1)
- Improve error handling in classic error case with proper fallback (C3)
- Improve TanStack converter TODO comment with known gap details (M5)
- Document @ts-expect-error on clone() middlewares access (S1)
- Add JSDoc to AgentFactoryContext.abortController (M4)
- Fix duplicate import and clean up react-router example
- Update docs AgentFactoryContext reference
Attachment queue & previews:
- Image lightbox with View Transition API morph animation
- Video lightbox with native controls and play button overlay
- Document lightbox (PDF via blob URL, text inline, info card fallback)
- Drop zone overlay with upload icon
- Filename preservation via InputContent metadata
- Proper video thumbnail sizing and play/pause indicator
- Fix attachment queue positioning (max-w-3xl constraint)
- Padding between X button and content for audio/document cards
- Document filenames wrap instead of truncating
Attachments config:
- onUploadFailed callback for validation/upload errors (file-too-large, invalid-type, upload-failed)
- onUpload accepts sync or async returns
- AttachmentUploadResult discriminated union with explicit interfaces
- Metadata field on Attachment and onUpload return type
AG-UI version bump:
- Bump @ag-ui/client, @ag-ui/core, @ag-ui/encoder, @ag-ui/proto to 0.0.51
- Remove process.env Vite workaround (fixed upstream in 0.0.51)
Deprecation lifecycle:
- @deprecated JSDoc on all legacy image upload APIs
- ImageRenderer, ImageRendererProps, ImageUpload type, imageUploadsEnabled prop,
inputFileAccept prop, ImageRenderer prop, AIMessage.image, ImageData
- Codemod at codemods/migrate-attachments.ts (15 tests)
- Migration guide updated with codemod instructions and new type shapes
Docs:
- New guide: docs/(root)/multimodal-attachments.mdx
- Updated migration guide with onUpload return type, metadata, codemod section
- Cross-links from prebuilt-components and migration guide
- Label change: "Add photos or files" → "Add attachments"
Tests:
- CopilotChat.attachments.test.tsx — 5 tests for onUploadFailed
- migrate-attachments codemod — 15 tests
Add a new example app at examples/v2/react-router demonstrating CopilotKit
with React Router v7 (SSR/framework mode) and TanStack AI as the default agent.
- React Router v7 SSR with Hono server via react-router-hono-server
- CopilotKit runtime mounted as a Hono route on the same server
- TanStackAIAgent: thin AbstractAgent wrapper that accepts a chat() factory
callback, giving users full type safety over TanStack AI's adapter/model config
- Proper AG-UI event normalization bridging TanStack AI's event format to
what CopilotKit's @ag-ui/client pipeline expects
- Full-page CopilotChat UI with Tailwind CSS v4
Alem Tuzlak