TanStack · AlemTuzlak · Apr 15, 2026 · Apr 15, 2026 · Apr 16, 2026 · Apr 16, 2026
diff --git a/.changeset/svelte-callback-propagation.md b/.changeset/svelte-callback-propagation.md
@@ -0,0 +1,7 @@
+---
+'@tanstack/ai-svelte': patch
+---
+
+fix(ai-svelte): propagate `createChat` callback changes uniformly
+
+`onResponse`, `onChunk`, and `onCustomEvent` were passed as direct references to the underlying `ChatClient`, while `onFinish` and `onError` were wrapped to read from `options.onX?.(...)` at call time. This meant callers who mutated the options object in-place (or invoked `client.updateOptions(...)`) would see their replacement propagate for the latter two but silently miss for the former three. All five user-supplied callbacks now go through the same indirection, matching the React / Preact / Vue / Solid sibling wrappers.
diff --git a/docs/adapters/openai.md b/docs/adapters/openai.md
@@ -6,7 +6,7 @@ description: "Use OpenAI models with TanStack AI — GPT-4o, GPT-5, DALL-E image
 keywords:
   - tanstack ai
   - openai
-  - gpt-4o
+  - gpt-5.2
   - gpt-5
   - dall-e
   - whisper

diff --git a/docs/adapters/openrouter.md b/docs/adapters/openrouter.md
@@ -126,7 +126,7 @@ const stream = chat({
   messages,
   modelOptions: {
     models: [
-      "openai/gpt-4o",
+      "openai/gpt-5.2",
       "anthropic/claude-3.5-sonnet",
       "google/gemini-pro",
     ],

diff --git a/docs/advanced/debug-logging.md b/docs/advanced/debug-logging.md
@@ -27,7 +27,7 @@ import { chat } from "@tanstack/ai";
 import { openaiText } from "@tanstack/ai-openai";
 
 const stream = chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages: [{ role: "user", content: "Hello" }],
   debug: true,
 });
@@ -36,7 +36,7 @@ const stream = chat({
 Every internal event now prints to the console with a `[tanstack-ai:<category>]` prefix:
 
 ```
-[tanstack-ai:request] activity=chat provider=openai model=gpt-4o messages=1 tools=0 stream=true
+[tanstack-ai:request] activity=chat provider=openai model=gpt-5.2 messages=1 tools=0 stream=true
 [tanstack-ai:agentLoop] run started
 [tanstack-ai:provider] provider=openai type=response.output_text.delta
 [tanstack-ai:output] type=TEXT_MESSAGE_CONTENT
@@ -49,7 +49,7 @@ Pass a `DebugConfig` object instead of `true`. Every unspecified category defaul
 
 ```typescript
 chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages,
   debug: { middleware: false }, // everything except middleware
 });
@@ -59,7 +59,7 @@ If you want to see ONLY a specific set of categories, set the rest to `false` ex
 
 ```typescript
 chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages,
   debug: {
     provider: true,
@@ -91,7 +91,7 @@ const logger: Logger = {
 };
 
 chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages,
   debug: { logger }, // all categories on, piped to pino
 });

diff --git a/docs/advanced/extend-adapter.md b/docs/advanced/extend-adapter.md
@@ -35,7 +35,7 @@ const myOpenai = extendAdapter(openaiText, [
 ])
 
 // Use with original models - full type inference preserved
-const gpt4Adapter = myOpenai('gpt-4o')
+const gpt4Adapter = myOpenai('gpt-5.2')
 
 // Use with custom models - your custom types are applied
 const customAdapter = myOpenai('my-fine-tuned-gpt4')
@@ -109,7 +109,7 @@ import { openaiText } from '@tanstack/ai-openai'
 const myOpenai = extendAdapter(openaiText, [createModel('custom-model', ['text'])])
 
 // ✅ Original models work with their original types
-const a1 = myOpenai('gpt-4o')
+const a1 = myOpenai('gpt-5.2')
 
 // ✅ Custom models work with your defined types
 const a2 = myOpenai('custom-model')

diff --git a/docs/advanced/middleware.md b/docs/advanced/middleware.md
@@ -43,7 +43,7 @@ const logger: ChatMiddleware = {
 };
 
 const stream = chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages: [{ role: "user", content: "Hello" }],
   middleware: [logger],
 });
@@ -444,7 +444,7 @@ Middleware execute in array order. The ordering matters for hooks that pipe or s
 
 ```typescript
 const stream = chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages,
   middleware: [authMiddleware, loggingMiddleware, cachingMiddleware],
 });
@@ -474,7 +474,7 @@ import { chat } from "@tanstack/ai";
 import { toolCacheMiddleware } from "@tanstack/ai/middlewares";
 
 const stream = chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages,
   tools: [weatherTool, stockTool],
   middleware: [

diff --git a/docs/advanced/otel.md b/docs/advanced/otel.md
@@ -38,7 +38,7 @@ const otel = otelMiddleware({
 })
 
 const result = await chat({
-  adapter: openaiText('gpt-4o'),
+  adapter: openaiText('gpt-5.2'),
   messages: [{ role: 'user', content: 'hi' }],
   middleware: [otel],
   stream: false,
@@ -50,11 +50,11 @@ const result = await chat({
 ### Spans
 
 ```text
-chat gpt-4o              (root, kind: INTERNAL)
-├── chat gpt-4o #0       (iteration, kind: CLIENT)
+chat gpt-5.2              (root, kind: INTERNAL)
+├── chat gpt-5.2 #0       (iteration, kind: CLIENT)
 │   ├── execute_tool get_weather
 │   └── execute_tool get_time
-└── chat gpt-4o #1       (iteration, kind: CLIENT)
+└── chat gpt-5.2 #1       (iteration, kind: CLIENT)
 ```
 
 Iteration spans are numbered (`#0`, `#1`, ...) so distinct iterations of the same chat are easy to pick apart in trace viewers.

diff --git a/docs/api/ai-preact.md b/docs/api/ai-preact.md
@@ -66,7 +66,7 @@ Extends `ChatClientOptions` from `@tanstack/ai-client`:
 - `initialMessages?` - Initial messages array
 - `id?` - Unique identifier for this chat instance
 - `threadId?` - Thread ID for AG-UI run correlation. Persists across sends; auto-generated if omitted
-- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-4o' }`)
+- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-5.2' }`)
 - `body?` - **Deprecated.** Use `forwardedProps` instead. Still works for backward compatibility; values are merged into `forwardedProps` on the wire
 - `onResponse?` - Callback when response is received
 - `onChunk?` - Callback when stream chunk is received

diff --git a/docs/api/ai-react.md b/docs/api/ai-react.md
@@ -66,7 +66,7 @@ Extends `ChatClientOptions` from `@tanstack/ai-client`:
 - `initialMessages?` - Initial messages array
 - `id?` - Unique identifier for this chat instance
 - `threadId?` - Thread ID for AG-UI run correlation. Persists across sends; auto-generated if omitted
-- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-4o' }`)
+- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-5.2' }`)
 - `body?` - **Deprecated.** Use `forwardedProps` instead. Still works for backward compatibility; values are merged into `forwardedProps` on the wire
 - `onResponse?` - Callback when response is received
 - `onChunk?` - Callback when stream chunk is received

diff --git a/docs/api/ai-solid.md b/docs/api/ai-solid.md
@@ -67,7 +67,7 @@ Extends `ChatClientOptions` from `@tanstack/ai-client`:
 - `initialMessages?` - Initial messages array
 - `id?` - Unique identifier for this chat instance
 - `threadId?` - Thread ID for AG-UI run correlation. Persists across sends; auto-generated if omitted
-- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-4o' }`)
+- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-5.2' }`)
 - `body?` - **Deprecated.** Use `forwardedProps` instead. Still works for backward compatibility; values are merged into `forwardedProps` on the wire
 - `onResponse?` - Callback when response is received
 - `onChunk?` - Callback when stream chunk is received

diff --git a/docs/api/ai-svelte.md b/docs/api/ai-svelte.md
@@ -62,7 +62,7 @@ Extends `ChatClientOptions` from `@tanstack/ai-client` (minus internal state cal
 - `initialMessages?` - Initial messages array
 - `id?` - Unique identifier for this chat instance
 - `threadId?` - Thread ID for AG-UI run correlation. Persists across sends; auto-generated if omitted
-- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-4o' }`)
+- `forwardedProps?` - Arbitrary client-controlled JSON forwarded to the server in the AG-UI `RunAgentInput.forwardedProps` field (e.g., `{ provider: 'openai', model: 'gpt-5.2' }`)
 - `body?` - **Deprecated.** Use `forwardedProps` instead. Still works for backward compatibility; values are merged into `forwardedProps` on the wire
 - `live?` - Enable live subscription mode (subscribes on creation)
 - `onResponse?` - Callback when response is received

diff --git a/docs/api/ai.md b/docs/api/ai.md
@@ -205,7 +205,7 @@ import { openaiText } from "@tanstack/ai-openai";
 export async function POST(req: Request) {
   const params = await chatParamsFromRequest(req);
   const stream = chat({
-    adapter: openaiText("gpt-4o"),
+    adapter: openaiText("gpt-5.2"),
     messages: params.messages,
     tools: serverTools,
   });
@@ -246,7 +246,7 @@ import { chat, chatParamsFromRequest, mergeAgentTools } from "@tanstack/ai";
 
 const params = await chatParamsFromRequest(req);
 const stream = chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   messages: params.messages,
   tools: mergeAgentTools(serverTools, params.tools),
 });

diff --git a/docs/chat/streaming.md b/docs/chat/streaming.md
@@ -87,6 +87,71 @@ TanStack AI implements the [AG-UI Protocol](https://docs.ag-ui.com/introduction)
 
 > **Tip:** Some models expose their internal reasoning as thinking content that streams before the response. See [Thinking & Reasoning](./thinking-content).
 
+### Type-Safe Tool Call Events
+
+When you pass typed tools (defined with `toolDefinition()` and Zod schemas) to `chat()`, the stream chunks automatically carry type information for tool call events. The `toolName` field narrows to the union of your tool name literals, and the `input` field on `TOOL_CALL_END` events is typed as the union of your tool input schemas:
+
+```typescript
+import { chat, toolDefinition } from "@tanstack/ai";
+import { openaiText } from "@tanstack/ai-openai";
+import { z } from "zod";
+
+const weatherTool = toolDefinition({
+  name: "get_weather",
+  description: "Get weather for a location",
+  inputSchema: z.object({
+    location: z.string(),
+    unit: z.enum(["celsius", "fahrenheit"]).optional(),
+  }),
+});
+
+const stream = chat({
+  adapter: openaiText("gpt-5.2"),
+  messages,
+  tools: [weatherTool],
+});
+
+for await (const chunk of stream) {
+  if (chunk.type === "TOOL_CALL_END") {
+    chunk.toolName; // ✅ typed as "get_weather" (not string)
+    chunk.input;    // ✅ typed as { location: string; unit?: "celsius" | "fahrenheit" } | undefined
+  }
+}
+```
+
+Without typed tools, `toolName` defaults to `string` and `input` defaults to `unknown` — the same behavior as before. The type narrowing is automatic when you use `toolDefinition()` with Zod schemas.
+
+When multiple tools are provided, tool call events form a **discriminated union** — checking `toolName` narrows `input` to that specific tool's type:
+
+```typescript
+const searchTool = toolDefinition({
+  name: "search",
+  description: "Search the web",
+  inputSchema: z.object({ query: z.string() }),
+});
+
+const stream = chat({
+  adapter: openaiText("gpt-5.2"),
+  messages,
+  tools: [weatherTool, searchTool],
+});
+
+for await (const chunk of stream) {
+  if (chunk.type === "TOOL_CALL_END") {
+    if (chunk.toolName === "get_weather") {
+      // ✅ input is narrowed to { location: string; unit?: "celsius" | "fahrenheit" }
+      console.log(`Weather in ${chunk.input?.location}`);
+    }
+    if (chunk.toolName === "search") {
+      // ✅ input is narrowed to { query: string }
+      console.log(`Searched for: ${chunk.input?.query}`);
+    }
+  }
+}
+```
+
+> **Tip:** The typed stream chunk type is exported as `TypedStreamChunk<TTools>` if you need to annotate variables or function parameters. When used without type arguments, `TypedStreamChunk` is equivalent to `StreamChunk`.
+
 ### Thinking Chunks
 
 Thinking/reasoning is represented by AG-UI events `STEP_STARTED` and `STEP_FINISHED`. They stream separately from the final response text:

diff --git a/docs/code-mode/code-mode-with-skills.md b/docs/code-mode/code-mode-with-skills.md
@@ -101,7 +101,7 @@ const { toolsRegistry, systemPrompt, selectedSkills } = await codeModeWithSkills
 })
 
 const stream = chat({
-  adapter: openaiText('gpt-4o'),  // strong model for reasoning
+  adapter: openaiText('gpt-5.2'),  // strong model for reasoning
   toolRegistry: toolsRegistry,
   messages,
   systemPrompts: ['You are a helpful assistant.', systemPrompt],
@@ -189,7 +189,7 @@ const skillsPrompt = createSkillsSystemPrompt({
 
 // 5. Assemble and call chat()
 const stream = chat({
-  adapter: openaiText('gpt-4o'),
+  adapter: openaiText('gpt-5.2'),
   tools: [codeModeTool, ...managementTools, ...skillTools],
   messages,
   systemPrompts: [BASE_PROMPT, codeModePrompt, skillsPrompt],

diff --git a/docs/code-mode/code-mode.md b/docs/code-mode/code-mode.md
@@ -100,7 +100,7 @@ import { chat } from "@tanstack/ai";
 import { openaiText } from "@tanstack/ai-openai";
 
 const result = await chat({
-  adapter: openaiText("gpt-4o"),
+  adapter: openaiText("gpt-5.2"),
   systemPrompts: [
     "You are a helpful weather assistant.",
     systemPrompt,

diff --git a/docs/community-adapters/cencori.md b/docs/community-adapters/cencori.md
@@ -27,7 +27,7 @@ npm install @cencori/ai-sdk
 import { chat } from "@tanstack/ai";
 import { cencori } from "@cencori/ai-sdk/tanstack";
 
-const adapter = cencori("gpt-4o");
+const adapter = cencori("gpt-5.2");
 
 for await (const chunk of chat({
   adapter,
@@ -49,7 +49,7 @@ const cencori = createCencori({
   baseUrl: "https://cencori.com", // Optional
 });
 
-const adapter = cencori("gpt-4o");
+const adapter = cencori("gpt-5.2");
 ```
 
 ## Streaming
@@ -79,7 +79,7 @@ for await (const chunk of chat({
 import { chat } from "@tanstack/ai";
 import { cencori } from "@cencori/ai-sdk/tanstack";
 
-const adapter = cencori("gpt-4o");
+const adapter = cencori("gpt-5.2");
 
 for await (const chunk of chat({
   adapter,
@@ -110,7 +110,7 @@ Switch between providers with a single parameter:
 import { cencori } from "@cencori/ai-sdk/tanstack";
 
 // OpenAI
-const openai = cencori("gpt-4o");
+const openai = cencori("gpt-5.2");
 
 // Anthropic
 const anthropic = cencori("claude-3-5-sonnet");
@@ -131,7 +131,7 @@ All responses use the same unified format regardless of provider.
 
 | Provider | Models |
 |----------|--------|
-| OpenAI | `gpt-5`, `gpt-4o`, `gpt-4o-mini`, `o3`, `o1` |
+| OpenAI | `gpt-5`, `gpt-5.2`, `gpt-4o-mini`, `o3`, `o1` |
 | Anthropic | `claude-opus-4`, `claude-sonnet-4`, `claude-3-5-sonnet` |
 | Google | `gemini-3-pro`, `gemini-2.5-flash`, `gemini-2.0-flash` |
 | xAI | `grok-4`, `grok-3` |
@@ -168,7 +168,7 @@ Creates a Cencori adapter using environment variables.
 
 **Parameters:**
 
-- `model` - Model name (e.g., `"gpt-4o"`, `"claude-3-5-sonnet"`, `"gemini-2.5-flash"`)
+- `model` - Model name (e.g., `"gpt-5.2"`, `"claude-3-5-sonnet"`, `"gemini-2.5-flash"`)
 
 **Returns:** A Cencori TanStack AI adapter instance.
 

diff --git a/docs/community-adapters/cloudflare.md b/docs/community-adapters/cloudflare.md
@@ -202,7 +202,7 @@ import {
   createOpenRouterChat,
 } from "@cloudflare/tanstack-ai";
 
-const openai = createOpenAiChat("gpt-4o", {
+const openai = createOpenAiChat("gpt-5.2", {
   binding: env.AI.gateway("my-gateway-id"),
 });
 
@@ -214,7 +214,7 @@ const grok = createGrokChat("grok-4", {
   binding: env.AI.gateway("my-gateway-id"),
 });
 
-const openrouter = createOpenRouterChat("openai/gpt-4o", {
+const openrouter = createOpenRouterChat("openai/gpt-5.2", {
   binding: env.AI.gateway("my-gateway-id"),
 });
 ```
@@ -224,7 +224,7 @@ Or use credentials for non-Worker environments:
 ```typescript
 import { createOpenAiChat } from "@cloudflare/tanstack-ai";
 
-const adapter = createOpenAiChat("gpt-4o", {
+const adapter = createOpenAiChat("gpt-5.2", {
   accountId: "your-account-id",
   gatewayId: "your-gateway-id",
   cfApiKey: "your-cf-api-key",
@@ -237,7 +237,7 @@ const adapter = createOpenAiChat("gpt-4o", {
 Both binding and credentials modes support cache configuration:
 
 ```typescript
-const adapter = createOpenAiChat("gpt-4o", {
+const adapter = createOpenAiChat("gpt-5.2", {
   binding: env.AI.gateway("my-gateway-id"),
   skipCache: false,
   cacheTtl: 3600,
-Original file line number
+Diff line change
@@ Expand Up @@
     keywords:
       - tanstack ai
       - openai
-      - gpt-4o
+      - gpt-5.2
       - gpt-5
       - dall-e
       - whisper
@@ Expand Down @@