VoltAgent Files

Major Changes

• #462 23ecea4 Thanks @omeraplak! - feat!: Migrate from AI SDK v4 to v5 with new adapter pattern

  Breaking Changes

  • Removed all v4 exports and utilities:
    • convertToUIMessages() - Message conversion utility
    • toDataStream(), mergeIntoDataStream(), formatDataStreamPart() - Data stream utilities
    • filterUIMessageParts (alias: rejectUIMessageParts) - Message filtering
    • isSubAgent (alias: isSubAgentStreamPart) - Guard utilities
    • Type exports: UIMessage, UIMessagePart, ToolInvocationUIPart, DataStream, DataStreamString, DataStreamOptions
  • Upgraded from AI SDK v4 (^4.3.16) to v5 (^5.0.8)

  New Features

  • New adapter pattern following LangChain/LlamaIndex conventions:
    • toUIMessageStream(stream, callbacks?) - Converts VoltAgent's StreamPart to AI SDK v5's UIMessageChunk
    • toDataStreamResponse(stream, options?) - Creates HTTP Response for Next.js API routes
    • StreamCallbacks type for stream event handling
  • Full AI SDK v5 compatibility:
    • Proper UIMessageChunk streaming
    • Support for reasoning-delta chunks (start/delta/end pattern)
    • Tool call and result streaming with dynamic tool names
    • Text streaming with proper start/end events
    • SubAgent metadata via data-subagent chunks

  Migration Guide

  Data Stream Usage

  Before (v4):

  ```typescript import { toDataStream, mergeIntoDataStream } from "@voltagent/vercel-ui";

  // Direct stream conversion const stream = toDataStream(result.fullStream, { sendUsage: true, sendReasoning: false, });

  // Or merging into existing stream mergeIntoDataStream(writer, result.fullStream); ```

  After (v5):

  ```typescript import { toDataStreamResponse } from "@voltagent/vercel-ui";

  // Direct HTTP response return toDataStreamResponse(result.fullStream);

  // Or with manual stream handling import { toUIMessageStream } from "@voltagent/vercel-ui"; const uiStream = toUIMessageStream(result.fullStream); ```

  Message Conversion

  Before (v4):

  ```typescript import { convertToUIMessages } from "@voltagent/vercel-ui";

  const uiMessages = convertToUIMessages(operationContext); ```

  After (v5):

  ```typescript // Message conversion is now handled by AI SDK v5's built-in utilities import { convertToModelMessages } from "ai";

  const modelMessages = convertToModelMessages(messages); ```

  Type Imports

  Before (v4):

  typescript import type { UIMessage, UIMessagePart } from "@voltagent/vercel-ui";

  After (v5):

  typescript import type { UIMessage, UIMessagePart } from "ai";

Patch Changes

• #462 23ecea4 Thanks @omeraplak! - Update Zod to v3.25.0 for compatibility with Vercel AI@5
  • Updated Zod dependency to ^3.25.0 across all packages
  • Maintained compatibility with zod-from-json-schema@0.0.5
  • Fixed TypeScript declaration build hanging issue
  • Resolved circular dependency issues in the build process