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Migration guide: 2.x → 3.x

VoltAgent 3.x aligns the framework with AI SDK v7. This is a major release, so the runtime boundary is intentionally stricter: Node.js 22 or later and ESM-only packages. The agent, memory, tool, workflow, guardrail, observability, server, MCP, A2A, AG-UI, and VoltOps features remain available, but some AI SDK-facing names and result fields changed.

If you are still on 1.x, follow the Migration guide: 1.x → 2.x section first, then come back here.

What changed

  • Runtime: Node.js >=22 is required.
  • Module format: VoltAgent 3.x is ESM-only. CommonJS require("@voltagent/core") is no longer supported.
  • AI SDK: ai moves to ^7.
  • AI SDK provider packages need v7-compatible majors, for example @ai-sdk/openai@^4.
  • Zod: zod moves to ^4. Zod 3 is no longer a supported peer dependency in VoltAgent 3.x.
  • AI SDK callbacks use onEnd and onStepEnd.
  • stepCountIs is now isStepCount.
  • streamText detailed events are exposed as stream. fullStream remains as a deprecated alias during the transition.
  • Structured output uses output, not experimental_output.
  • generateObject and streamObject are still available as deprecated compatibility wrappers. Prefer generateText/streamText with Output.object.

Step 1. Upgrade your runtime to Node.js 22

Before installing VoltAgent 3.x, make sure local development, CI, and production all use Node.js 22 or later:

node --version

Update your application package metadata:

{
"engines": {
"node": ">=22"
}
}

If you cannot move off Node.js 20 yet, stay on VoltAgent 2.x until your runtime is ready.

Step 2. Move your app to ESM

VoltAgent 3.x publishes ESM runtime entrypoints. Use ESM imports and mark your package as a module:

{
"type": "module"
}

Before:

const { Agent } = require("@voltagent/core");
const { openai } = require("@ai-sdk/openai");

After:

import { Agent } from "@voltagent/core";
import { openai } from "@ai-sdk/openai";

For TypeScript projects, use a module resolution mode that matches your toolchain. NodeNext and Bundler are both common choices:

{
"compilerOptions": {
"module": "NodeNext",
"moduleResolution": "NodeNext"
}
}

Step 3. Update packages

3.1 Update VoltAgent packages

Use the Volt CLI if your project already has it:

npm run volt update

Or update the packages manually:

pnpm add @voltagent/core@latest @voltagent/server-hono@latest @voltagent/logger@latest

If you use memory/storage/server/protocol packages, update all @voltagent/* packages to the same major version.

3.2 Update AI SDK packages

Install AI SDK v7 and v7-compatible provider packages:

pnpm add ai@^7 @ai-sdk/openai@^4
pnpm add @ai-sdk/provider@^4 @ai-sdk/provider-utils@^5
pnpm add zod@^4

If you use AI SDK UI helpers:

pnpm add @ai-sdk/react@^4

Provider package majors vary by provider. Common upgrades:

PackageUse with AI SDK v7
@ai-sdk/openai^4
@ai-sdk/anthropic^4
@ai-sdk/google^4
@ai-sdk/azure^4
@ai-sdk/groq^4
@ai-sdk/mistral^4
@ai-sdk/perplexity^4
@ai-sdk/openai-compatible^3
@ai-sdk/amazon-bedrock^5
@ai-sdk/google-vertex^5

After changing dependencies, reinstall and refresh the lockfile:

pnpm install

3.3 Update Zod

VoltAgent 3.x is Zod 4-only. Remove Zod 3 pins from your app and templates:

pnpm add zod@^4

If you have custom code that imports Zod 3-specific internals or zod/v3, update it to the public Zod 4 API before upgrading VoltAgent.

Step 4. Keep using the AI SDK-style agent call shape

The object-style call shape introduced in 2.x remains the preferred API. Keep AI SDK generation settings at the top level and VoltAgent runtime options under voltagent:

VoltAgent 3.x derives most public generation options from AI SDK v7 generateText and streamText, so AI SDK settings such as timeout, headers, include, activeTools, toolOrder, experimental_download, onChunk, and stream lifecycle callbacks can be used directly on the agent call.

const result = await agent.generateText({
prompt: "Summarize this ticket",
temperature: 0.2,
maxOutputTokens: 500,
voltagent: {
memory: {
userId: "user-123",
conversationId: "ticket-456",
},
context: {
requestId: "req-789",
},
},
});

The same shape works for streamText:

const result = await agent.streamText({
prompt: "Write a short release note",
timeout: {
totalMs: 30_000,
chunkMs: 5_000,
},
include: {
rawChunks: true,
},
onChunk: async ({ chunk }) => {
// Native AI SDK stream callback.
},
voltagent: {
memory: {
userId: "user-123",
conversationId: "release-456",
},
},
});

VoltAgent composes a small set of fields instead of passing them through unchanged: model, prompt/messages, tools, abortSignal, maxRetries, onStepEnd, onEnd/onFinish, and onError. You still pass the callbacks at the top level; VoltAgent invokes them after its memory, guardrail, hook, tracing, and recovery work has run.

Top-level AI SDK toolsContext is passed through for native AI SDK tools that declare contextSchema. Use it for per-tool AI SDK execution context. Top-level AI SDK runtimeContext, telemetry, and experimental_telemetry are intentionally not supported on VoltAgent calls. Use voltagent.context for per-call application context and VoltAgent observability/OpenTelemetry configuration for telemetry.

Legacy positional calls are still accepted:

const result = await agent.generateText("Summarize this ticket", {
memory: {
userId: "user-123",
conversationId: "ticket-456",
},
});

For new code, prefer the object-style form because it matches AI SDK field names and keeps VoltAgent-specific runtime concerns explicit.

Step 5. Rename stepCountIs to isStepCount

AI SDK v7 renamed stepCountIs to isStepCount. VoltAgent re-exports isStepCount for convenience.

Before:

import { stepCountIs } from "ai";

const result = await agent.generateText({
prompt: "Research and summarize",
stopWhen: stepCountIs(5),
});

After:

import { isStepCount } from "@voltagent/core";

const result = await agent.generateText({
prompt: "Research and summarize",
stopWhen: isStepCount(5),
});

You can also import isStepCount directly from ai.

Step 6. Rename stream result access from fullStream to stream

AI SDK v7 exposes detailed stream parts on stream. VoltAgent follows that name. fullStream remains available as a deprecated alias, but new code should use stream.

Before:

const result = await agent.streamText("Write a changelog");

for await (const part of result.fullStream) {
if (part.type === "text-delta") {
process.stdout.write(part.text);
}
}

After:

const result = await agent.streamText("Write a changelog");

for await (const part of result.stream) {
if (part.type === "text-delta") {
process.stdout.write(part.text);
}
}

textStream, toUIMessageStream, toUIMessageStreamResponse, pipeTextStreamToResponse, and toTextStreamResponse remain available on stream results.

Step 7. Rename lifecycle callbacks

AI SDK v7 uses onEnd and onStepEnd. Update callback names in per-call options and hooks.

Before:

const result = await agent.streamText({
prompt: "Plan the task",
onFinish: async (event) => {
console.log(event.finishReason);
},
hooks: {
onStepFinish: async ({ step }) => {
console.log(step.finishReason);
},
},
});

After:

const result = await agent.streamText({
prompt: "Plan the task",
onEnd: async (event) => {
console.log(event.finishReason);
},
hooks: {
onStepEnd: async ({ step }) => {
console.log(step.finishReason);
},
},
});

Agent-level hooks use the same names:

const agent = new Agent({
name: "assistant",
model,
instructions: "You are a helpful assistant.",
hooks: {
onEnd: async ({ output, error }) => {
// Persist metadata, emit logs, or update your own analytics.
},
onStepEnd: async ({ step }) => {
// Inspect each AI SDK step.
},
},
});

Step 8. Use instructions for system prompts

AI SDK v7 separates instructions from regular model messages. For VoltAgent agents, keep using the instructions field:

const agent = new Agent({
name: "support",
model,
instructions: "Answer support questions with short, direct replies.",
});

For per-call overrides, prefer instructions:

const result = await agent.generateText({
prompt: "Draft a reply",
instructions: "Write in a calm support tone.",
});

VoltAgent normalizes older system-message input where possible, but new code should not add { role: "system" } messages to the request message list.

Step 9. Update structured output

Use AI SDK v7 output with Output.object. Do not use experimental_output.

Before:

const result = await agent.generateText({
prompt: "Create a user profile",
experimental_output: Output.object({ schema }),
});

After:

import { Output } from "ai";

const result = await agent.generateText({
prompt: "Create a user profile",
output: Output.object({ schema }),
});

console.log(result.output);

generateObject and streamObject still work as compatibility wrappers, but they are deprecated. Prefer:

const result = await agent.generateText({
prompt: "Create a user profile",
output: Output.object({ schema }),
});

For streaming structured output:

const result = await agent.streamText({
prompt: "Create a user profile",
output: Output.object({ schema }),
});

for await (const partial of result.partialOutputStream ?? []) {
console.log(partial);
}

Step 10. Prefer AI SDK-style tools for new custom tools

VoltAgent 3.x accepts AI SDK-style ToolSet records directly on agents. For new code, prefer AI SDK tool() from ai. The tool name comes from the tools object key and the schema field is inputSchema.

Before:

import { createTool } from "@voltagent/core";
import { z } from "zod";

const weatherTool = createTool({
name: "get_weather",
description: "Get weather for a city",
parameters: z.object({
city: z.string(),
}),
execute: async ({ city }) => {
return { city, temperature: 72 };
},
});

After:

import { tool } from "ai";
import { Agent } from "@voltagent/core";
import { z } from "zod";

const agent = new Agent({
name: "assistant",
model,
instructions: "You are a helpful assistant.",
tools: {
get_weather: tool({
description: "Get weather for a city",
inputSchema: z.object({
city: z.string(),
}),
execute: async ({ city }) => {
return { city, temperature: 72 };
},
}),
},
});

Native AI SDK tool features such as contextSchema and call-level toolsContext pass through unchanged:

import { tool } from "ai";

const agent = new Agent({
name: "assistant",
model,
instructions: "You are a helpful assistant.",
tools: {
get_weather: tool({
description: "Get weather for a city",
inputSchema: z.object({
city: z.string(),
}),
contextSchema: z.object({
apiKey: z.string(),
defaultUnit: z.enum(["celsius", "fahrenheit"]),
}),
execute: async ({ city }, { context }) => {
return fetchWeather(city, {
apiKey: context.apiKey,
unit: context.defaultUnit,
});
},
}),
},
});

await agent.generateText({
prompt: "What is the weather in San Francisco?",
toolsContext: {
get_weather: {
apiKey: process.env.WEATHER_API_KEY!,
defaultUnit: "fahrenheit",
},
},
});

VoltAgent-specific tool metadata is optional and additive. Use withVoltAgentMetadata to attach it to a raw AI SDK tool without changing the native tool definition or sending metadata to the model provider:

import { tool } from "ai";
import { withVoltAgentMetadata } from "@voltagent/core";

const refundCustomer = withVoltAgentMetadata(
tool({
description: "Refund a customer order",
inputSchema: z.object({
orderId: z.string(),
reason: z.string(),
}),
contextSchema: z.object({
actorId: z.string(),
permissions: z.array(z.string()),
}),
execute: async ({ orderId, reason }, { context }) => {
if (!context.permissions.includes("refund:write")) {
throw new Error("Not allowed to refund orders");
}

return issueRefund({
orderId,
reason,
actorId: context.actorId,
});
},
}),
{
name: "Refund Customer",
purpose: "Issue customer refunds",
tags: ["billing", "dangerous", "customer-support"],
metadata: {
owner: "payments-team",
riskLevel: "high",
},
}
);

For new approval flows, prefer AI SDK v7's native call-level toolApproval option. It takes precedence over tool-level needsApproval:

import { tool } from "ai";

const result = await agent.generateText({
prompt: "Delete the stale report",
tools: {
delete_file: tool({
description: "Delete a file",
inputSchema: z.object({
path: z.string(),
}),
execute: async ({ path }) => deleteFile(path),
}),
},
toolApproval: {
delete_file: "user-approval",
},
});

createTool is now a legacy compatibility helper for existing class-style tools. New custom tools should use tool(). When migrating from createTool to tool():

  • move name to the tools object key.
  • rename parameters to inputSchema.
  • move tags, hooks, and other VoltAgent-only metadata to withVoltAgentMetadata.
  • use VoltAgent metadata name only as display metadata. Telemetry and tool calls keep using the ToolSet key as canonical tool.name; metadata name is exposed as tool.display_name.
  • keep execute, outputSchema, providerOptions, and toModelOutput in the AI SDK tool definition.
  • keep AI SDK contextSchema in the tool definition and pass matching per-tool values through call-level toolsContext.
  • use voltagent.context on the agent call for general per-request application context, and VoltAgent observability/OpenTelemetry configuration for telemetry.

Use call-level toolApproval when approval should be controlled per request, per user, or per runtime context. Use voltagent.needsApproval only for static tool metadata or compatibility with existing VoltAgent tool policies.

If you type the AI SDK tool execution options, import the v7-compatible type from @ai-sdk/provider-utils:

import type { ToolExecutionOptions } from "@ai-sdk/provider-utils";

If you use toModelOutput, keep the AI SDK v7 argument object shape:

const screenshotTool = tool({
description: "Capture a screenshot",
inputSchema: z.object({
url: z.string(),
}),
execute: async ({ url }) => captureScreenshot(url),
toModelOutput: ({ output }) => ({
type: "content",
value: [
{
type: "media",
data: output.imageBase64,
mediaType: "image/png",
},
],
}),
});

tool() from @voltagent/core remains available as a convenience wrapper when you prefer inline voltagent metadata, but raw AI SDK tools are first-class and do not require a VoltAgent wrapper.

Provider-defined AI SDK tools can also be passed in the same tools object. Provider-owned tools are still passed through to AI SDK unchanged; use withVoltAgentMetadata when VoltAgent should apply hooks, preserve tags, or attach approval/API metadata around a user-executed AI SDK tool.

Step 11. Update direct AI SDK tests and mocks

If your tests import AI SDK mocks directly, update them to the v7 mock names and result shapes:

import { MockLanguageModelV3 } from "ai/test";

Also update assertions that read AI SDK stream results:

expect(result.stream).toBeDefined();

Use result.output for structured output assertions instead of result.experimental_output.

Step 12. Validate the migration

Run your normal checks after the package and code changes:

pnpm lint
pnpm build
pnpm test

For VoltAgent monorepos, also validate package boundaries and docs/examples if applicable:

pnpm build:all
pnpm test:all
pnpm publint:all
pnpm --dir website build

Quick checklist

  • Node.js is >=22 everywhere.
  • The app is ESM ("type": "module" or ESM output from your framework).
  • ai is ^7.
  • AI SDK provider packages are v7-compatible.
  • @ai-sdk/react is ^4 if used.
  • zod is ^4.
  • CommonJS require() imports are replaced with ESM imports.
  • stepCountIs is replaced with isStepCount.
  • result.fullStream is replaced with result.stream in new code.
  • onFinish/onStepFinish usages are replaced with onEnd/onStepEnd.
  • experimental_output is replaced with output.
  • New custom tools use AI SDK tool() + inputSchema; VoltAgent-only metadata uses withVoltAgentMetadata when needed.
  • New approval flows use call-level toolApproval where possible.
  • New structured output code uses generateText/streamText with Output.object.

Migration guide: 1.x → 2.x

VoltAgent 2.x aligns the framework with AI SDK v6 and adds new features. There are no breaking changes in VoltAgent APIs. If you only use VoltAgent APIs, follow the steps below. If your app calls AI SDK functions directly, also review the upstream AI SDK v6 migration guide.

If you are still on 0.1.x, scroll down to the Migration guide: 0.1.x → 1.x section first, then come back here for the 1.x → 2.x upgrade.

Step 1. Update packages

If you already have the Volt CLI installed, use:

npm run volt update

This command updates only @voltagent/* dependencies. You still need to align ai and @ai-sdk/* packages in the next step.

If you do not have the CLI yet, install it and add a script:

npx @voltagent/cli init

This command installs @voltagent/cli, adds the volt script, and creates the .voltagent folder in your project.

Then run:

npm run volt update

1.2 Align AI SDK packages

If you ran npm run volt update, you can skip the @voltagent/* line below. Otherwise, update both VoltAgent and AI SDK packages:

pnpm add @voltagent/core@latest @voltagent/server-hono@latest @voltagent/libsql@latest @voltagent/logger@latest
pnpm add ai@^6 @ai-sdk/openai@^3 @ai-sdk/provider@^3 @ai-sdk/provider-utils@^4

Notes:

  • If you use other providers, upgrade them to @ai-sdk/*@^3 (e.g., @ai-sdk/anthropic, @ai-sdk/google, @ai-sdk/azure).
  • If you use useChat or other UI helpers, upgrade @ai-sdk/react to ^3.
  • If you are in a monorepo, update all @voltagent/* packages to the same major version.

Existing positional calls still work:

const result = await agent.generateText("Summarize this ticket", {
temperature: 0.2,
memory: {
userId: "user-123",
conversationId: "ticket-456",
},
context: {
requestId: "req-789",
},
});

For new code, prefer the AI SDK-style object shape. Keep model generation settings at the top level and move VoltAgent runtime options under voltagent:

const result = await agent.generateText({
prompt: "Summarize this ticket",
temperature: 0.2,
voltagent: {
memory: {
userId: "user-123",
conversationId: "ticket-456",
},
context: {
requestId: "req-789",
},
},
});

The same shape works for streamText. REST requests use the same namespace inside options.voltagent:

{
"input": "Summarize this ticket",
"options": {
"temperature": 0.2,
"voltagent": {
"memory": {
"userId": "user-123",
"conversationId": "ticket-456"
},
"context": {
"requestId": "req-789"
}
}
}
}

Legacy top-level runtime options such as memory, userId, conversationId, context, feedback, hooks, guardrails, and requestHeaders are still accepted during the transition. If both legacy fields and voltagent.* are provided, voltagent.* takes precedence.

Step 3. Update custom tools (only if you use advanced tool hooks)

3.1 Tool output mapping signature change

If you use toModelOutput, it now receives { output }:

toModelOutput: ({ output }) => ({ type: "text", value: output }),

3.2 Tool execution options type rename (if you type it)

If you type the second execute parameter, use:

import type { ToolExecutionOptions } from "@ai-sdk/provider-utils";

Step 4. Structured output (if you use generateObject/streamObject)

VoltAgent 2.x deprecates generateObject and streamObject. Migrate to generateText/streamText with Output.object.

Before (1.x):

import { z } from "zod";

const schema = z.object({
name: z.string(),
age: z.number(),
});

const result = await agent.generateObject("Create a profile", schema);
console.log(result.object);
const stream = await agent.streamObject("Create a profile", schema);

for await (const partial of stream.partialObjectStream) {
console.log(partial);
}

After (2.x):

import { Output } from "ai";
import { z } from "zod";

const schema = z.object({
name: z.string(),
age: z.number(),
});

const result = await agent.generateText({
prompt: "Create a profile",
output: Output.object({ schema }),
});
console.log(result.output);
const stream = await agent.streamText({
prompt: "Create a profile",
output: Output.object({ schema }),
});

for await (const partial of stream.partialOutputStream ?? []) {
console.log(partial);
}

Step 5. Tests (if you use AI SDK mocks directly)

Update V2 mocks to V3 mocks:

import { MockLanguageModelV3 } from "ai/test";

Migration guide: 0.1.x → 1.x

Welcome to VoltAgent 1.x! This release brings the architectural improvements you've been asking for - native ai-sdk integration, truly modular components, and production-ready observability. Your agents are about to get a serious upgrade.

This guide is built for real-world migrations. Copy-paste the commands, follow the checklists, ship your update. No fluff, just the changes you need to know.

Need help? Hit a snag during migration? We've got you covered:

  • Open an issue on GitHub - we're tracking migration experiences closely
  • Join our Discord for real-time help from the community and core team

Here's what we'll cover:

  • What changed and why (high-level rationale)
  • Quick migration steps (copy-paste friendly)
  • Detailed changes (API-by-API, with examples)

Overview: What changed and why

VoltAgent 1.x is a complete architectural refinement. We stripped away unnecessary abstractions, embraced native ai-sdk integration, and made everything pluggable:

  • Native ai-sdk integration: The custom LLM provider layer and @voltagent/vercel-ai are removed. Apps pass ai-sdk models directly (works with any ai-sdk provider).
  • Modular server: The built-in HTTP server is removed from core. Use pluggable providers (recommended: @voltagent/server-hono).
  • Memory V2: A clean adapter-based architecture for storage/embeddings/vector search and structured working memory.
  • Observability (OpenTelemetry): Legacy telemetry exporter is removed. Observability now uses OpenTelemetry with optional span/log processors and storage.
  • Developer ergonomics: Clear peer dependency on ai, improved logger support in SSR/Edge (via globalThis), and convenience exports.

Benefits:

  • Smaller surface area in core, better portability (Node/Edge/Workers).
  • First-class ai-sdk support and predictable results/streams.
  • Composable memory: scale from in-memory to LibSQL/PostgreSQL/Supabase, plus semantic search.
  • Standardized observability (OTel) with optional web socket streaming/logging.

Step 1. Update Packages (@1)

Uninstall legacy provider/UI packages and install the new modular server + memory packages. Also add the base ai library and a provider.

Uninstall (legacy):

npm uninstall @voltagent/vercel-ai @voltagent/vercel-ui
# yarn remove @voltagent/vercel-ai @voltagent/vercel-ui
# pnpm remove @voltagent/vercel-ai @voltagent/vercel-ui

Upgrade/install (required):

npm install @voltagent/core@latest @voltagent/server-hono@latest @voltagent/libsql@latest @voltagent/logger@latest ai
# yarn add @voltagent/core@latest @voltagent/server-hono@latest @voltagent/libsql@latest @voltagent/logger@latest ai@latest
# pnpm add @voltagent/core@latest @voltagent/server-hono@latest @voltagent/libsql@latest @voltagent/logger@latest ai@latest
  • ai: Base Vercel AI SDK library used by VoltAgent 1.x (peer of @voltagent/core)
  • @ai-sdk/openai: Example provider; choose any compatible provider (@ai-sdk/anthropic, @ai-sdk/google, etc.)
  • @voltagent/server-hono: New pluggable HTTP server provider (replaces built-in server)
  • @voltagent/libsql: LibSQL/Turso memory adapter (replaces built-in LibSQL in core)

Optional adapters:

  • @voltagent/postgres: PostgreSQL storage adapter
  • @voltagent/supabase: Supabase storage adapter

Note: @voltagent/core@1.x declares ai@^5 as a peer dependency. Your application must install ai. If you want to import ai-sdk providers directly, install those packages too. If ai is missing, you will get a module resolution error at runtime when calling generation methods.

Node runtime requirement:

  • The repo targets Node >= 20. Please ensure your deployment matches.

Step 2. Update Code

Update your code as follows (highlighted lines are new in 1.x). Note: logger usage isn't new; keep your existing logger setup or use the example below.

// REMOVE (0.1.x):
// import { VercelAIProvider } from "@voltagent/vercel-ai";

import { VoltAgent, Agent, Memory } from "@voltagent/core";
import { LibSQLMemoryAdapter } from "@voltagent/libsql";
import { honoServer } from "@voltagent/server-hono";
import { createPinoLogger } from "@voltagent/logger";

const logger = createPinoLogger({ name: "my-app", level: "info" });

const memory = new Memory({
storage: new LibSQLMemoryAdapter({ url: "file:./.voltagent/memory.db" }),
});

const agent = new Agent({
name: "my-app",
instructions: "Helpful assistant",
// REMOVE (0.1.x): llm: new VercelAIProvider(),
model: "openai/gpt-4o-mini",
memory,
});

new VoltAgent({
agents: { agent },
server: honoServer(),
logger,
});

Remove in your existing code (0.1.x):

  • import { VercelAIProvider } from "@voltagent/vercel-ai";
  • llm: new VercelAIProvider(),
  • Built-in server options on VoltAgent (e.g., port, enableSwaggerUI, autoStart)

Add to your app (1.x):

  • import { Memory } from "@voltagent/core";
  • import { LibSQLMemoryAdapter } from "@voltagent/libsql";
  • import { honoServer } from "@voltagent/server-hono";
  • Configure memory: new Memory({ storage: new LibSQLMemoryAdapter({ url }) })
  • Pass server: honoServer() to new VoltAgent({...})

Summary of changes:

  • Delete: VercelAIProvider import and llm: new VercelAIProvider()
  • Delete: Built-in server options (port, enableSwaggerUI, autoStart, custom endpoints on core)
  • Add: Memory + LibSQLMemoryAdapter for persistent LibSQL/Turso-backed memory
  • Add: honoServer() as the server provider
  • Keep: model: "openai/..." (or any ai-sdk provider), or use model: "provider/model"

Custom routes and auth (server):

new VoltAgent({
agents: { agent },
server: honoServer({
port: 3141, // default
enableSwaggerUI: true, // optional
configureApp: (app) => {
app.get("/api/health", (c) => c.json({ status: "ok" }));
},
// Auth (optional)
// authNext: {
// provider: jwtAuth({ secret: process.env.JWT_SECRET! }),
// publicRoutes: ["GET /health", "GET /metrics"],
// },
}),
});

Detailed Changes

Observability (OpenTelemetry)

What changed:

  • Legacy telemetry/* and the telemetry exporter were removed from core.
  • Observability now uses OpenTelemetry and can be enabled for production with only environment variables. No code changes are required.

New APIs (from @voltagent/core):

  • VoltAgentObservability (created automatically unless you pass your own)
  • Optional processors: LocalStorageSpanProcessor, WebSocketSpanProcessor, WebSocketLogProcessor
  • In-memory adapter and OTel helpers (Span, SpanKind, SpanStatusCode, etc.)

Minimal usage (recommended):

  1. Add keys to your .env:
# .env
VOLTAGENT_PUBLIC_KEY=pk_...
VOLTAGENT_SECRET_KEY=sk_...
  1. Run your app normally. Remote export auto-enables when valid keys are present. Local, real-time debugging via the VoltOps Console stays available either way.

Learn more

Notes:

  • If you previously used the deprecated telemetryExporter or wired observability via VoltOpsClient, remove that code. The .env keys are sufficient.
  • When keys are missing/invalid, VoltAgent continues with local debugging only (no remote export).

Advanced (optional):

  • Provide a custom VoltAgentObservability to tune sampling/batching or override defaults. This is not required for typical setups.

Remove llm provider and @voltagent/vercel-ai

VoltAgent no longer uses a custom provider wrapper. The @voltagent/vercel-ai package has been removed, and the llm prop on Agent is no longer supported. VoltAgent now integrates directly with the Vercel AI SDK (ai) and is fully compatible with all ai-sdk providers.

What changed

  • Removed: @voltagent/vercel-ai package and VercelAIProvider usage
  • Removed: llm prop on Agent
  • Kept: model prop on Agent (now pass an ai-sdk LanguageModel directly)
  • Call settings: pass ai-sdk call settings (e.g., temperature, maxOutputTokens) in method options as before

Before (0.1.x)

import { Agent } from "@voltagent/core";
import { VercelAIProvider } from "@voltagent/vercel-ai";

const agent = new Agent({
name: "my-app",
instructions: "Helpful assistant",
llm: new VercelAIProvider(),
model: "openai/gpt-4o-mini",
});

After (1.x)

import { Agent } from "@voltagent/core";

const agent = new Agent({
name: "my-app",
instructions: "Helpful assistant",
// VoltAgent uses ai-sdk directly - just provide a model
model: "openai/gpt-4o-mini",
});

You can swap openai/... for any provider string, e.g. "anthropic/claude-3-5-sonnet", "google/gemini-1.5-pro", etc.

Or use a model string:

import { Agent } from "@voltagent/core";

const agent = new Agent({
name: "my-app",
instructions: "Helpful assistant",
model: "openai/gpt-4o-mini",
});

Package changes

  • Uninstall legacy provider:
    • npm: npm uninstall @voltagent/vercel-ai
    • yarn: yarn remove @voltagent/vercel-ai
    • pnpm: pnpm remove @voltagent/vercel-ai
  • Install the ai base library:
    • npm: npm install ai
    • yarn: yarn add ai
    • pnpm: pnpm add ai
  • Install provider packages only if you plan to import them:
    • npm: npm install @ai-sdk/openai
    • yarn: yarn add @ai-sdk/openai
    • pnpm: pnpm add @ai-sdk/openai

Note: @voltagent/core@1.x declares ai@^5 as a peer dependency. Your application must install ai. If you want to import ai-sdk providers directly, install those packages too. If ai is missing, you will get a module resolution error at runtime when calling generation methods.

Code changes checklist

  • Remove import { VercelAIProvider } from "@voltagent/vercel-ai" from all files
  • Remove llm: new VercelAIProvider() from Agent configuration
  • Keep model: ... and either import the appropriate ai-sdk provider or use a provider/model string
  • Move provider: { ... } call settings to top-level options (e.g., temperature, maxOutputTokens, topP, stopSequences)
  • Put provider-specific knobs under providerOptions if needed
  • Remove deprecated memoryOptions from Agent constructor; configure limits on your Memory instance (e.g., storageLimit) or adapter

Example call settings (unchanged style):

const res = await agent.generateText("Hello", {
temperature: 0.3,
maxOutputTokens: 256,
providerOptions: {
someProviderSpecificOption: {
foo: "bar",
},
},
});

Common errors after upgrade

  • Type error: "Object literal may only specify known properties, and 'llm' does not exist..." → Remove the llm prop
  • Module not found: @voltagent/vercel-ai → Uninstall the package and remove imports

Environment variables

Your existing provider keys still apply (e.g., OPENAI_API_KEY, ANTHROPIC_API_KEY, etc.). Configure them as required by ai-sdk providers.

Change: Default memory is now InMemory; new Memory class

VoltAgent 1.x introduces a new Memory class that unifies conversation history, optional vector search, and working-memory features. By default, if you do not configure memory, the agent uses in-memory storage.

What changed

  • Default memory: In-memory storage by default (no persistence)
  • New API: memory: new Memory({ storage: <Adapter> })
  • Legacy LibSQLStorage usage is replaced with LibSQLMemoryAdapter as a storage adapter
  • Optional adapters: InMemoryStorageAdapter (core), PostgreSQLMemoryAdapter (@voltagent/postgres), SupabaseMemoryAdapter (@voltagent/supabase), LibSQLMemoryAdapter (@voltagent/libsql)
  • New capabilities: Embedding-powered vector search and working-memory support (optional)

Before (0.1.x)

import { Agent } from "@voltagent/core";
import { VercelAIProvider } from "@voltagent/vercel-ai";
import { LibSQLStorage } from "@voltagent/libsql";

const agent = new Agent({
name: "my-agent",
instructions: "A helpful assistant that answers questions without using tools",
llm: new VercelAIProvider(),
model: "openai/gpt-4o-mini",
// Persistent memory
memory: new LibSQLStorage({
url: "file:./.voltagent/memory.db",
}),
});

After (1.x)

import { Agent, Memory } from "@voltagent/core";
import { LibSQLMemoryAdapter } from "@voltagent/libsql";

const agent = new Agent({
name: "my-agent",
instructions: "A helpful assistant that answers questions without using tools",
model: "openai/gpt-4o-mini",
// Optional: persistent memory (remove to use default in-memory)
memory: new Memory({
storage: new LibSQLMemoryAdapter({
url: "file:./.voltagent/memory.db",
}),
}),
});

Optional: Vector search and working memory

To enable semantic search and working-memory features, add an embedding model string and a vector adapter. For example, using ai-sdk embeddings and the in-memory vector store:

import { Memory, InMemoryVectorAdapter } from "@voltagent/core";

const memory = new Memory({
storage: new LibSQLMemoryAdapter({ url: "file:./.voltagent/memory.db" }),
embedding: "openai/text-embedding-3-small",
vector: new InMemoryVectorAdapter(),
// optional working-memory config
workingMemory: {
schema: {
/* zod-like schema or config */
},
},
});

Pick the storage adapter that best fits your deployment: in-memory (development), LibSQL/Turso (file or serverless SQLite), PostgreSQL, or Supabase.

Supabase users:

Change: ai-sdk v5 result passthrough + context

VoltAgent methods now return ai-sdk v5 results directly. We only add a context property to carry the OperationContext map alongside the result. This applies to:

  • generateText
  • streamText
  • generateObject
  • streamObject

Before (0.1.x)

  • Responses could differ per provider wrapper.
  • fullStream availability and event types were provider-dependent.

After (1.x)

  • Result objects match ai-sdk v5. Use ai-sdk docs for fields/methods.
  • context: Map<string | symbol, unknown> is added by VoltAgent.
  • fullStream is the ai-sdk stream; event shapes depend on your chosen model/provider.

streamObject rename

  • The partial stream from streamObject is now exposed as partialObjectStream (ai-sdk v5).
  • Replace any response.objectStream usages with response.partialObjectStream.

Change: Subagent fullStream forwarding config

The addSubAgentPrefix option on supervisorConfig.fullStreamEventForwarding has been removed.

Before (0.1.x)

supervisorConfig: {
fullStreamEventForwarding: {
types: ["tool-call", "tool-result", "text-delta"],
addSubAgentPrefix: true,
},
}

After (1.x)

supervisorConfig: {
fullStreamEventForwarding: {
types: ["tool-call", "tool-result", "text-delta"],
},
}

If you want prefixed labels, use the stream metadata from ai-sdk and add it yourself:

for await (const evt of response.stream) {
if (evt.subAgentName && evt.type === "tool-call") {
console.log(`[${evt.subAgentName}] Using: ${evt.toolName}`);
}
}

Example (streamText):

const res = await agent.streamText("hi");

// ai-sdk v7 stream
if (res.stream) {
for await (const part of res.stream) {
if (part.type === "text-delta") process.stdout.write(part.text);
else if (part.type === "tool-call") console.log("tool:", part.toolName);
else if (part.type === "tool-result") console.log("done:", part.toolName);
else if (part.type === "finish") console.log("usage:", part.usage);
}
}

// VoltAgent extra
console.log("context keys:", [...res.context.keys()]);

Example (generateText):

const out = await agent.generateText("hello");
console.log(out.text); // ai-sdk property
console.log(out.usage); // ai-sdk property
console.log(out.context); // VoltAgent Map

stopWhen override (advanced)

  • You can pass a custom ai-sdk stopWhen predicate in method options to control when to stop step execution.
  • This overrides VoltAgent's default isStepCount(maxSteps) guard.
  • Be cautious: permissive predicates can lead to long-running or looping generations; overly strict ones may stop before tools complete.

prepareStep callback (advanced)

  • You can pass an ai-sdk prepareStep callback in AgentOptions or in per-call method options to control tool availability, tool choice, and other settings before each step.
  • Per-call prepareStep overrides the agent-level default.
  • Example: force text-only output after the first step:
    const agent = new Agent({
    name: "my-agent",
    model,
    prepareStep: ({ steps }) => (steps.length > 0 ? { toolChoice: "none" } : {}),
    });

Built-in server removed; use @voltagent/server-hono

VoltAgent 1.x decouples the HTTP server from @voltagent/core. The built-in server is removed in favor of pluggable server providers. The recommended provider is @voltagent/server-hono (powered by Hono). Default port remains 3141.

What changed

  • Removed from core: port, enableSwaggerUI, autoStart, custom endpoint registration
  • New: server option accepts a server provider (e.g., honoServer())
  • Custom routes: use configureApp callback on the server provider
  • New: Optional authentication support (JWT) in @voltagent/server-hono

Install

  • npm: npm install @voltagent/server-hono
  • yarn: yarn add @voltagent/server-hono
  • pnpm: pnpm add @voltagent/server-hono

Before (0.1.x)

import { VoltAgent } from "@voltagent/core";

new VoltAgent({
agents: { agent },
port: 3141,
enableSwaggerUI: true,
// server auto-started
});

After (1.x)

import { VoltAgent } from "@voltagent/core";
import { honoServer } from "@voltagent/server-hono";

new VoltAgent({
agents: { agent },
server: honoServer({
port: 3141, // default
enableSwaggerUI: true, // optional
}),
});

Custom routes

new VoltAgent({
agents: { agent },
server: honoServer({
configureApp: (app) => {
app.get("/api/health", (c) => c.json({ status: "ok" }));
},
}),
});

Authentication (optional)

Use authNext to separate public, console, and user routes:

import { honoServer } from "@voltagent/server-hono";
import { jwtAuth } from "@voltagent/server-core";

new VoltAgent({
agents: { agent },
server: honoServer({
authNext: {
provider: jwtAuth({ secret: process.env.JWT_SECRET! }),
publicRoutes: ["GET /health", "GET /metrics"],
},
}),
});

Within agents, you can read the authenticated user from the OperationContext (context.get("user")) inside hooks.

abortController option renamed to abortSignal

Agent methods now accept abortSignal (an AbortSignal) instead of abortController.

Before (0.1.x):

const ac = new AbortController();
const res = await agent.generateText("...", { abortController: ac });

After (1.x):

const ac = new AbortController();
const res = await agent.generateText("...", { abortSignal: ac.signal });

Notes:

  • Tools still access an internal operationContext.abortController and its signal.
  • You only need to pass abortSignal to agent calls; propagation is handled internally.

Message helpers now use UIMessage (breaking)

What changed:

  • Message-level helpers now accept and return UIMessage (ai-sdk UI message type) instead of BaseMessage:
    • addTimestampToMessage(message: UIMessage, ...) => UIMessage
    • prependToMessage(message: UIMessage, ...) => UIMessage
    • appendToMessage(message: UIMessage, ...) => UIMessage
    • hasContent(message: UIMessage) => boolean
    • mapMessageContent(message: UIMessage, transformer) => UIMessage
  • Content-level helpers are unchanged and still operate on MessageContent (string | parts[]).

Why:

  • The Agent pipeline and hooks operate on ai-sdk UIMessage[]. Aligning helpers eliminates type mismatches and extra conversions in hooks (e.g., onPrepareMessages).

Before (0.1.x):

import { addTimestampToMessage, mapMessageContent } from "@voltagent/core/utils";
import type { BaseMessage } from "@voltagent/core";

const msg: BaseMessage = { role: "user", content: "hello" };
const stamped = addTimestampToMessage(msg, "10:30"); // returns BaseMessage

After (1.x):

import { addTimestampToMessage, mapMessageContent } from "@voltagent/core/utils";
import type { UIMessage } from "ai";

const msg: UIMessage = {
id: "m1",
role: "user",
parts: [{ type: "text", text: "hello" }],
metadata: {},
} as UIMessage;
const stamped = addTimestampToMessage(msg, "10:30"); // returns UIMessage

Notes:

  • If you were calling helpers with BaseMessage, update those call sites to construct UIMessage objects (id, role, parts, metadata). Agent onPrepareMessages already provides UIMessage[].
  • No changes needed for transformTextContent, extractText, etc. — they still operate on MessageContent.

Hook arg rename: onHandoff sourcesourceAgent (breaking)

What changed:

  • onHandoff hook argument object renamed the source agent field from source to sourceAgent for clarity and consistency with internal APIs.

Before (0.1.x):

onHandoff: ({ agent, source }) => {
console.log(`${source.name}${agent.name}`);
};

After (1.x):

onHandoff: ({ agent, sourceAgent }) => {
console.log(`${sourceAgent.name}${agent.name}`);
};

Action:

  • Update all onHandoff usages in your code and docs to use sourceAgent.

Server Core (typed routes, schemas, handlers)

The core HTTP surface moved into @voltagent/server-core and is consumed by @voltagent/server-hono:

  • Typed route definitions and schemas for agents/workflows/logs/observability
  • WebSocket utilities (log/observability streaming)
  • Auth helpers and server utilities

If you previously relied on core’s internal server exports (custom endpoints, registry), migrate to @voltagent/server-core types and helpers, then run via @voltagent/server-hono.

Convenience exports & logger

  • Convenience from @voltagent/core: zodSchemaToJsonUI, isStepCount, hasToolCall, convertUsage.
  • Logger helpers: LoggerProxy, getGlobalLogger, getGlobalLogBuffer. Logger is SSR/Edge-friendly via globalThis in Next.js.

Runtime & TypeScript

  • Node >= 20 is recommended/required for 1.x deployments.
  • TypeScript 5.x recommended (repo uses 5.9). Typical tsconfig basics: moduleResolution matching your toolchain (NodeNext/Bundler), skipLibCheck: true, and DOM libs only if needed.

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