diff --git a/.github/workflows/sync-asyncapi.yml b/.github/workflows/sync-asyncapi.yml
index 78f2b969..d5339878 100644
--- a/.github/workflows/sync-asyncapi.yml
+++ b/.github/workflows/sync-asyncapi.yml
@@ -62,7 +62,7 @@ jobs:
       - name: Check for changes
         id: changes
         run: |
-          if git diff --quiet -- packages/platform/asyncapi.json packages/platform/src/client/modules/builder.events.generated.ts; then
+          if git diff --quiet -- packages/platform/asyncapi.json packages/platform/src/client/modules/chat.events.generated.ts; then
             echo "changed=false" >> "$GITHUB_OUTPUT"
             echo "✅ asyncapi.json and the event types are up to date"
           else
@@ -91,7 +91,7 @@ jobs:
           git config user.name "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
           git checkout -B "$BRANCH"
-          git add packages/platform/asyncapi.json packages/platform/src/client/modules/builder.events.generated.ts
+          git add packages/platform/asyncapi.json packages/platform/src/client/modules/chat.events.generated.ts
           git commit -m "chore(platform): sync asyncapi.json and the event types from production"
 
           pr=$(gh pr list --head "$BRANCH" --state open --json number --jq '.[0].number')
@@ -103,7 +103,7 @@ jobs:
           # Rebuilt from main every run, so the branch never drifts or conflicts.
           git push --force origin "$BRANCH"
 
-          body="Refreshes \`packages/platform/asyncapi.json\` from $ASYNCAPI_URL and regenerates \`builder.events.generated.ts\`. The docs build and the Platform SDK tests passed on this change. Checked against production every hour."
+          body="Refreshes \`packages/platform/asyncapi.json\` from $ASYNCAPI_URL and regenerates \`chat.events.generated.ts\`. The docs build and the Platform SDK tests passed on this change. Checked against production every hour."
           if [ -z "$pr" ]; then
             gh pr create --head "$BRANCH" --base main --title "Sync Platform SDK events from production" --body "$body"
           fi
diff --git a/packages/platform/CHANGELOG.md b/packages/platform/CHANGELOG.md
index ae1f67d1..8c9855d2 100644
--- a/packages/platform/CHANGELOG.md
+++ b/packages/platform/CHANGELOG.md
@@ -1,5 +1,30 @@
 # Changelog
 
+## Unreleased
+
+**Breaking.** Base44 calls it the AI chat, so the client and the webhook events say `chat`, not
+`builder`.
+
+### Client
+
+| Before | After |
+| --- | --- |
+| `client.builder` | `client.chat` |
+| `BuilderModule` | `ChatModule` |
+| `BuilderSession` | `ChatSession` |
+| `BuilderInitOptions` | `ChatInitOptions` |
+
+```ts
+const chat = client.chat.init({ getSession, onError });
+```
+
+### Webhooks
+
+`chat.turn_started.v1` and `chat.turn_ended.v1` replace `builder.turn_started.v1` and
+`builder.turn_ended.v1`, with the same payloads. Their types are `ChatTurnStartedV1Data` and
+`ChatTurnEndedV1Data`. Base44 no longer sends the old names, so an endpoint that selected them
+must select `chat.turn_*` instead.
+
 ## 0.2.0
 
 **Breaking.** The client, its options and the event type names change, and events the SDK doesn't
diff --git a/packages/platform/README.md b/packages/platform/README.md
index addad586..3d9e22ed 100644
--- a/packages/platform/README.md
+++ b/packages/platform/README.md
@@ -7,8 +7,8 @@ npm install @base44/platform
 The Platform SDK for white-label platforms built on Base44. It is independent of the app SDK
 (`@base44/sdk`) and has two entrypoints:
 
-- `@base44/platform`, for the browser: implements the read-only white-label builder socket
-  contract. A partner's browser watches the builder chat of up to eight apps over the platform's
+- `@base44/platform`, for the browser: implements the read-only white-label live AI chat
+  contract. A partner's browser watches the AI chat of up to eight apps over the platform's
   shared socket. The workspace must have white-label sockets enabled; this SDK does not open sessions.
 - `@base44/platform/server`, for your backend: verify the webhooks Base44 sends when apps are
   created, published, unpublished, trashed or restored. See
@@ -18,24 +18,24 @@ The Platform SDK for white-label platforms built on Base44. It is independent of
 import { createPlatformClient } from "@base44/platform";
 
 const client = createPlatformClient();
-const builder = client.builder.init({
+const chat = client.chat.init({
   // Returns the body of POST /api/service/socket-sessions, unchanged.
   async getSession() {
-    const response = await fetch("/api/builder-socket-session", { method: "POST" });
+    const response = await fetch("/api/chat-socket-session", { method: "POST" });
     if (!response.ok) throw new Error("Session request failed");
     return response.json();
   },
   onError(error) { showConnectionError(error.code); },
 });
-const subscription = builder.subscribe(appId, {
+const subscription = chat.subscribe(appId, {
   onSnapshot(snapshot) { replaceAppState(snapshot); },
   async onEvent(event) { await applyEvent(event); }, // awaited before the next event
   onError(error) { showSubscriptionError(error.code); },
 });
-await builder.connect();
+await chat.connect();
 // On view teardown:
 subscription.unsubscribe();
-builder.close();
+chat.close();
 ```
 
 ## Receiving webhooks (server)
@@ -97,7 +97,7 @@ Delivery is at least once with no ordering guarantee: deduplicate on `event.id`,
 
 ## Sessions
 
-`/api/builder-socket-session` is your backend's route, not an SDK endpoint. It opens a
+`/api/chat-socket-session` is your backend's route, not an SDK endpoint. It opens a
 socket session with its workspace key (`apps:watch` scope) through
 `POST /api/service/socket-sessions` with `{ app_ids }`, and returns the response body
 to the browser. `getSession` returns that body unchanged: the SDK reads `session_token`,
@@ -107,7 +107,7 @@ backend adds or removes apps with `PUT`/`DELETE /api/service/socket-sessions/{se
 
 A session lasts one hour and is never extended. The token goes exclusively in
 CONNECT `auth.session_token`, never a URL, and the SDK keeps it in memory only. It
-is reused across automatic reconnects. `getSession` is called when a builder
+is reused across automatic reconnects. `getSession` is called when a chat
 session first connects, and again only when the server rejects the cached token or
 expires the session; the SDK then reconnects once with the new session. If the new
 session has a different `socket_url` or `socket_path`, the SDK closes the old socket,
@@ -123,26 +123,26 @@ older one, which stops with `session_replaced`. Open one session per page.
 
 `createPlatformClient()` creates a lightweight module container: no Socket.IO
 instance, timers, session request or network activity. It takes no options. Its
-`builder` module follows the server SDK's module-factory pattern.
+`chat` module follows the server SDK's module-factory pattern.
 
-`client.builder.init({ getSession, onError })` synchronously creates an independent
-`BuilderSession` without connecting or creating a socket. Repeated calls create separate sessions, each owning its own
+`client.chat.init({ getSession, onError })` synchronously creates an independent
+`ChatSession` without connecting or creating a socket. Repeated calls create separate sessions, each owning its own
 socket, listeners, subscriptions and cleanup. Close the returned session when its
 view is disposed; the root client and other sessions remain usable.
 
-`builder.connect()` fetches the first session, creates the socket at its address and
+`chat.connect()` fetches the first session, creates the socket at its address and
 resolves on CONNECT, before any snapshot. The socket uses the default namespace on the
 session's `socket_path`, WebSocket only, with a dedicated manager.
 Transport reconnection uses five attempts, starting at one second and capped at ten
 seconds with jitter; each attempt has a twenty-second timeout. A temporary server
 refusal is retried the same way. After exhaustion, a refusal or `session_replaced`,
-fix the cause and call `builder.connect()`.
+fix the cause and call `chat.connect()`.
 
-`builder.subscribe(appId, options)` returns a handle with `appId`, `active` and
+`chat.subscribe(appId, options)` returns a handle with `appId`, `active` and
 idempotent `unsubscribe()`. App IDs are 24 lowercase hexadecimal characters. One
-subscription per app and at most eight subscriptions are allowed per builder session.
-Subscriptions can be created before connecting. `builder.close()` is terminal for that
-session; call `client.builder.init(...)` again to start another.
+subscription per app and at most eight subscriptions are allowed per chat session.
+Subscriptions can be created before connecting. `chat.close()` is terminal for that
+session; call `client.chat.init(...)` again to start another.
 
 ## Snapshots and events
 
@@ -161,15 +161,15 @@ their exceptions are isolated so they cannot interrupt another app's delivery.
 
 ## Public shapes
 
-- `PlatformClient` (`client.types.ts`): the `builder` module.
-- `BuilderModule` (`modules/builder.types.ts`): lazy `init(options)` factory.
-- `BuilderInitOptions`: `getSession` and the connection-level `onError` observer.
+- `PlatformClient` (`client.types.ts`): the `chat` module.
+- `ChatModule` (`modules/chat.types.ts`): lazy `init(options)` factory.
+- `ChatInitOptions`: `getSession` and the connection-level `onError` observer.
 - `SocketSession`: the `session_token`, `socket_url` and `socket_path` that `getSession` returns.
-- `BuilderSession`: `connect()`, `subscribe(appId, options)`, `close()`.
+- `ChatSession`: `connect()`, `subscribe(appId, options)`, `close()`.
 - `SubscriptionOptions`: required `onSnapshot`, `onEvent` and `onError`.
 - `PlatformSubscription`: read-only `appId`, `active`, and `unsubscribe()`.
 - `PlatformEvent`, `PlatformEventMap`, `PlatformSnapshot`, `ToolCall`, `GuardApproval`
-  (`modules/builder.events.types.ts`), derived from the generated event types.
+  (`modules/chat.events.types.ts`), derived from the generated event types.
 - Error codes in `errors.types.ts`.
 
 `PlatformEvent` is a **discriminated union**: switch on `event.type` to narrow
@@ -186,7 +186,7 @@ redaction of generated prose or user content.
 ## Event types
 
 The socket protocol is defined by the service's AsyncAPI document, committed as
-`asyncapi.json`. `src/client/modules/builder.events.generated.ts` is generated from it with
+`asyncapi.json`. `src/client/modules/chat.events.generated.ts` is generated from it with
 `json-schema-to-typescript`: one type per schema, named after the backend model
 (`Message`, `StatusObject`, `QueueState`, one `*Call` per tool, one `*Approval` per
 guard), plus `ServerEventMap` and `ClientMessageMap`. Never edit it by hand.
@@ -229,16 +229,16 @@ exceptions, payloads and credentials are never attached.
 | `delivery_overflow` | 1,000 deliveries queued for the app; subscribe again for a fresh snapshot. |
 | `protocol_error` | Invalid routing or envelope. Stop and investigate. |
 | `handler_failed` | An application callback failed; fix it and subscribe again. |
-| `client_closed` | The builder session was explicitly closed; initialize another session. |
+| `client_closed` | The chat session was explicitly closed; initialize another session. |
 
 No SDK dependency, package version or lockfile changes are required. Socket.IO
 remains the existing SDK dependency. Chat commands and HTTP APIs are outside this entry point.
 
 ## React
 
-`@base44/platform/react` adds one hook, `useBase44Chat`, that runs a builder chat for one
+`@base44/platform/react` adds one hook, `useBase44Chat`, that runs the AI chat for one
 app on top of this client: it opens the live session and renews it, turns messages into items
-made for rendering, binds every question the builder asks to the step it belongs to. It renders nothing. React is an optional peer dependency, loaded only by this
+made for rendering, binds every question the AI asks to the step it belongs to. It renders nothing. React is an optional peer dependency, loaded only by this
 entry; the root entry stays framework-free.
 
 ```tsx
@@ -258,5 +258,5 @@ call with your credentials, so the browser never holds a key. The hook returns `
 the first, and the chat watches it while `appId` is `null`. A sent prompt shows at once as a
 `pending` item until Base44's own message arrives; a prompt sent mid-build waits in Base44's
 queue meanwhile. A question is a union on `kind` (`choice`, `secrets`, `approval`) and carries only the
-actions its kind allows, and declining is always one of them. As in Base44's builder, only the
+actions its kind allows, and declining is always one of them. As in Base44's app editor, only the
 last assistant message makes the chat wait; a kind this release doesn't know is declined for you. Every shape has JSDoc in `src/react/chat.types.ts`.
diff --git a/packages/platform/examples/client.ts b/packages/platform/examples/client.ts
index 3eae6187..db4dc9d7 100644
--- a/packages/platform/examples/client.ts
+++ b/packages/platform/examples/client.ts
@@ -1,17 +1,17 @@
 import { createPlatformClient, type PlatformEvent } from "@base44/platform";
 
 const client = createPlatformClient();
-const builder = client.builder.init({
+const chat = client.chat.init({
   // Your backend opens the session with its workspace key and returns the Create socket session body.
   async getSession() {
-    const response = await fetch("/api/builder-socket-session", { method: "POST" });
+    const response = await fetch("/api/chat-socket-session", { method: "POST" });
     if (!response.ok) throw new Error("Unable to open a socket session");
     return response.json();
   },
   onError(error) { console.error(error.code); },
 });
 
-const subscription = builder.subscribe("0123456789abcdef01234567", {
+const subscription = chat.subscribe("0123456789abcdef01234567", {
   onSnapshot(snapshot) {
     // Replace this app's state; merge messages by id to keep history older than the last 50.
     console.log(snapshot.status?.state, snapshot.messages.length);
@@ -27,7 +27,7 @@ const subscription = builder.subscribe("0123456789abcdef01234567", {
   },
 });
 
-await builder.connect();
+await chat.connect();
 // Later, during teardown:
 subscription.unsubscribe();
-builder.close();
+chat.close();
diff --git a/packages/platform/package.json b/packages/platform/package.json
index 33c7d1db..d009f2fe 100644
--- a/packages/platform/package.json
+++ b/packages/platform/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@base44/platform",
   "version": "0.3.0",
-  "description": "Base44 Platform SDK for white-label platforms: a browser client for watching the builder and a server entrypoint for webhooks",
+  "description": "Base44 Platform SDK for white-label platforms: a browser client for following the AI chat and a server entrypoint for webhooks",
   "main": "dist/client/index.js",
   "types": "dist/client/index.d.ts",
   "type": "module",
diff --git a/packages/platform/scripts/gen-events.mjs b/packages/platform/scripts/gen-events.mjs
index c9817795..942ba2fa 100644
--- a/packages/platform/scripts/gen-events.mjs
+++ b/packages/platform/scripts/gen-events.mjs
@@ -1,10 +1,10 @@
 #!/usr/bin/env node
-// Generates src/client/modules/builder.events.generated.ts from asyncapi.json. `--check` fails on drift instead.
+// Generates src/client/modules/chat.events.generated.ts from asyncapi.json. `--check` fails on drift instead.
 import { readFile, writeFile } from "node:fs/promises";
 import { compile } from "json-schema-to-typescript";
 
 const source = new URL("../asyncapi.json", import.meta.url);
-const target = new URL("../src/client/modules/builder.events.generated.ts", import.meta.url);
+const target = new URL("../src/client/modules/chat.events.generated.ts", import.meta.url);
 const doc = JSON.parse(await readFile(source, "utf8"));
 const schemas = doc.components.schemas;
 const refName = (ref) => ref.split("/").pop();
@@ -85,10 +85,10 @@ export const serverEventNames = ${JSON.stringify(serverEvents.map((event) => eve
 if (process.argv.includes("--check")) {
   const committed = await readFile(target, "utf8").catch(() => "");
   if (committed !== output) {
-    console.error("builder.events.generated.ts is out of date with asyncapi.json. Run `npm run gen:events -w @base44/platform` and commit the result.");
+    console.error("chat.events.generated.ts is out of date with asyncapi.json. Run `npm run gen:events -w @base44/platform` and commit the result.");
     process.exit(1);
   }
-  console.log("builder.events.generated.ts is up to date.");
+  console.log("chat.events.generated.ts is up to date.");
 } else {
   await writeFile(target, output);
   console.log(`Wrote ${Object.keys(schemas).length} schemas and ${serverEvents.length} server events.`);
diff --git a/packages/platform/scripts/mintlify-post-processing/appended-articles.json b/packages/platform/scripts/mintlify-post-processing/appended-articles.json
index 20874f6d..f5902ded 100644
--- a/packages/platform/scripts/mintlify-post-processing/appended-articles.json
+++ b/packages/platform/scripts/mintlify-post-processing/appended-articles.json
@@ -1,6 +1,6 @@
 {
-  "interfaces/builder": [
-    "interfaces/BuilderSession",
+  "interfaces/chat": [
+    "interfaces/ChatSession",
     "interfaces/SocketSession",
     "type-aliases/PlatformEvent",
     "interfaces/PlatformSnapshot"
diff --git a/packages/platform/scripts/mintlify-post-processing/page-sections.json b/packages/platform/scripts/mintlify-post-processing/page-sections.json
index a0bc0155..a9124098 100644
--- a/packages/platform/scripts/mintlify-post-processing/page-sections.json
+++ b/packages/platform/scripts/mintlify-post-processing/page-sections.json
@@ -1,6 +1,6 @@
 {
   "typesWithOwnMethods": {
-    "BuilderSession": "Session methods"
+    "ChatSession": "Session methods"
   },
   "typeDefinitionGroups": [
     ["SocketSession", "PlatformEvent", "PlatformSnapshot"],
diff --git a/packages/platform/scripts/mintlify-post-processing/types-to-expose.json b/packages/platform/scripts/mintlify-post-processing/types-to-expose.json
index 886ab129..69bd5166 100644
--- a/packages/platform/scripts/mintlify-post-processing/types-to-expose.json
+++ b/packages/platform/scripts/mintlify-post-processing/types-to-expose.json
@@ -1,7 +1,7 @@
 [
   "AppErrorCode",
-  "BuilderModule",
-  "BuilderSession",
+  "ChatModule",
+  "ChatSession",
   "PlatformEvent",
   "PlatformSnapshot",
   "PlatformSocketError",
diff --git a/packages/platform/scripts/webhook-event-types.json b/packages/platform/scripts/webhook-event-types.json
index 86074785..d1b229ca 100644
--- a/packages/platform/scripts/webhook-event-types.json
+++ b/packages/platform/scripts/webhook-event-types.json
@@ -5,6 +5,6 @@
   "app.deleted.v1",
   "app.restored.v1",
   "webhook.test.v1",
-  "builder.turn_started.v1",
-  "builder.turn_ended.v1"
+  "chat.turn_started.v1",
+  "chat.turn_ended.v1"
 ]
diff --git a/packages/platform/src/client/client.ts b/packages/platform/src/client/client.ts
index a3cf6598..3b9e551a 100644
--- a/packages/platform/src/client/client.ts
+++ b/packages/platform/src/client/client.ts
@@ -1,12 +1,12 @@
 import type { PlatformClient } from "./client.types.js";
-import { createBuilder } from "./modules/builder.js";
+import { createChat } from "./modules/chat.js";
 
 /**
  * Creates a platform client.
  *
  * This is the entry point of the Platform SDK. The client gives your white-label app editor
- * access to the platform's modules, such as [`builder`](/developers/references/platform-sdk/docs/interfaces/builder).
- * It takes no options and opens nothing: each builder session gets its socket session from the
+ * access to the platform's modules, such as [`chat`](/developers/references/platform-sdk/docs/interfaces/chat).
+ * It takes no options and opens nothing: each chat session gets its socket session from the
  * `getSession` you pass to `init()`.
  *
  * @returns A platform client with access to the platform's modules.
@@ -19,16 +19,16 @@ import { createBuilder } from "./modules/builder.js";
  * const client = createPlatformClient();
  *
  * // Use the client to follow the AI chat in an app
- * const builder = client.builder.init({
+ * const chat = client.chat.init({
  *   async getSession() {
- *     const response = await fetch('/api/builder-socket-session', { method: 'POST' });
+ *     const response = await fetch('/api/chat-socket-session', { method: 'POST' });
  *     return response.json();
  *   },
  *   onError: (error) => console.error(error.code),
  * });
- * await builder.connect();
+ * await chat.connect();
  * ```
  */
 export function createPlatformClient(): PlatformClient {
-  return Object.freeze({ builder: Object.freeze(createBuilder()) });
+  return Object.freeze({ chat: Object.freeze(createChat()) });
 }
diff --git a/packages/platform/src/client/client.types.ts b/packages/platform/src/client/client.types.ts
index 6ed309d5..042e2520 100644
--- a/packages/platform/src/client/client.types.ts
+++ b/packages/platform/src/client/client.types.ts
@@ -1,4 +1,4 @@
-import type { BuilderModule } from "./modules/builder.types.js";
+import type { ChatModule } from "./modules/chat.types.js";
 
 /**
  * The platform client.
@@ -6,6 +6,6 @@ import type { BuilderModule } from "./modules/builder.types.js";
  * Provides access to the platform's modules.
  */
 export interface PlatformClient {
-  /** [Builder module](/developers/references/platform-sdk/docs/interfaces/builder) for following the AI chat in your users' apps live. */
-  readonly builder: BuilderModule;
+  /** [Chat module](/developers/references/platform-sdk/docs/interfaces/chat) for following the AI chat in your users' apps live. */
+  readonly chat: ChatModule;
 }
diff --git a/packages/platform/src/client/errors.ts b/packages/platform/src/client/errors.ts
index 56d0fdee..a020576c 100644
--- a/packages/platform/src/client/errors.ts
+++ b/packages/platform/src/client/errors.ts
@@ -1,7 +1,7 @@
 import type { PlatformSocketErrorCode } from "./errors.types.js";
 
 /**
- * The error the SDK reports when something goes wrong in a builder session.
+ * The error the SDK reports when something goes wrong in a chat session.
  *
  * You don't create it. The SDK passes it to your `onError` callbacks, `connect()` rejects with it,
  * and `subscribe()` throws it. Check `code` to see what happened, then look the code up below:
@@ -15,14 +15,14 @@ import type { PlatformSocketErrorCode } from "./errors.types.js";
  * @example
  * ```typescript
  * // Handle session and app errors
- * const builder = client.builder.init({
+ * const chat = client.chat.init({
  *   // Session error codes: the whole session is affected
  *   onError(error) {
  *     if (error.code === 'session_revoked') showSignedOut();
  *   },
  * });
  *
- * builder.subscribe(appId, {
+ * chat.subscribe(appId, {
  *   onSnapshot: renderChat,
  *   onEvent: applyEvent,
  *   // App error codes: only this app is affected, and error.appId says which
diff --git a/packages/platform/src/client/index.ts b/packages/platform/src/client/index.ts
index b8f93fb1..0a10f78f 100644
--- a/packages/platform/src/client/index.ts
+++ b/packages/platform/src/client/index.ts
@@ -3,6 +3,6 @@ export { createPlatformClient } from "./client.js";
 export { PlatformSocketError } from "./errors.js";
 export type { AppErrorCode, PlatformSocketErrorCode, SessionErrorCode } from "./errors.types.js";
 export type { PlatformClient } from "./client.types.js";
-export type { BuilderModule, BuilderInitOptions, BuilderSession, PlatformSubscription, SocketSession, SubscriptionOptions } from "./modules/builder.types.js";
-export type { GuardApproval, PlatformEvent, PlatformEventMap, PlatformSnapshot, ToolCall } from "./modules/builder.events.types.js";
-export type * from "./modules/builder.events.generated.js";
+export type { ChatModule, ChatInitOptions, ChatSession, PlatformSubscription, SocketSession, SubscriptionOptions } from "./modules/chat.types.js";
+export type { GuardApproval, PlatformEvent, PlatformEventMap, PlatformSnapshot, ToolCall } from "./modules/chat.events.types.js";
+export type * from "./modules/chat.events.generated.js";
diff --git a/packages/platform/src/client/modules/builder.ts b/packages/platform/src/client/modules/builder.ts
deleted file mode 100644
index 4e71199f..00000000
--- a/packages/platform/src/client/modules/builder.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-import { BuilderSocket } from "./builder-socket.js";
-import type { BuilderModule } from "./builder.types.js";
-
-/** @internal */
-export function createBuilder(): BuilderModule {
-  return {
-    init(options) { return new BuilderSocket(options); },
-  };
-}
diff --git a/packages/platform/src/client/modules/builder-protocol.ts b/packages/platform/src/client/modules/chat-protocol.ts
similarity index 96%
rename from packages/platform/src/client/modules/builder-protocol.ts
rename to packages/platform/src/client/modules/chat-protocol.ts
index 7d979923..c0022f45 100644
--- a/packages/platform/src/client/modules/builder-protocol.ts
+++ b/packages/platform/src/client/modules/chat-protocol.ts
@@ -1,7 +1,7 @@
-import { serverEventNames, type ServerEventMap, type SessionEnded } from "./builder.events.generated.js";
+import { serverEventNames, type ServerEventMap, type SessionEnded } from "./chat.events.generated.js";
 import type { PlatformSocketErrorCode } from "../errors.types.js";
-import type { PlatformEvent, PlatformEventMap, PlatformSnapshot } from "./builder.events.types.js";
-import type { SocketSession } from "./builder.types.js";
+import type { PlatformEvent, PlatformEventMap, PlatformSnapshot } from "./chat.events.types.js";
+import type { SocketSession } from "./chat.types.js";
 
 const sessionEvents: readonly string[] = ["app.snapshot", "session.ended"];
 /** App events delivered to `onEvent`: every server event except the session events the socket handles. */
diff --git a/packages/platform/src/client/modules/builder-socket.ts b/packages/platform/src/client/modules/chat-socket.ts
similarity index 95%
rename from packages/platform/src/client/modules/builder-socket.ts
rename to packages/platform/src/client/modules/chat-socket.ts
index e9f73b7c..2805c539 100644
--- a/packages/platform/src/client/modules/builder-socket.ts
+++ b/packages/platform/src/client/modules/chat-socket.ts
@@ -1,17 +1,17 @@
 import { io, type Socket } from "socket.io-client";
 import { PlatformSocketError } from "../errors.js";
-import { appFromRoom, appPattern, decode, decodeSession, decodeSnapshot, eventNames, isUnknownEvent, object, roomFor, roomNotices, sessionEndings } from "./builder-protocol.js";
-import { notify, Subscription } from "./builder-subscription.js";
-import type { BuilderInitOptions, BuilderSession, PlatformSubscription, SocketSession, SubscriptionOptions } from "./builder.types.js";
+import { appFromRoom, appPattern, decode, decodeSession, decodeSnapshot, eventNames, isUnknownEvent, object, roomFor, roomNotices, sessionEndings } from "./chat-protocol.js";
+import { notify, Subscription } from "./chat-subscription.js";
+import type { ChatInitOptions, ChatSession, PlatformSubscription, SocketSession, SubscriptionOptions } from "./chat.types.js";
 
 const MAX_DENIAL_RETRIES = 5;
 
 /** @internal */
-export class BuilderSocket implements BuilderSession {
+export class ChatSocket implements ChatSession {
   private socket?: Socket;
   private address?: string;
   private readonly subscriptions = new Map<string, Subscription>();
-  private readonly options: BuilderInitOptions;
+  private readonly options: ChatInitOptions;
   private closed = false;
   // The session outlives reconnects; it is replaced only when the server rejects or expires its token.
   private session?: SocketSession;
@@ -25,7 +25,7 @@ export class BuilderSocket implements BuilderSession {
   private resolveConnect?: () => void;
   private rejectConnect?: (error: PlatformSocketError) => void;
 
-  constructor(options: BuilderInitOptions) {
+  constructor(options: ChatInitOptions) {
     this.options = { getSession: options.getSession, onError: options.onError };
   }
 
@@ -55,7 +55,7 @@ export class BuilderSocket implements BuilderSession {
   subscribe(appId: string, options: SubscriptionOptions): PlatformSubscription {
     if (this.closed) throw new PlatformSocketError("client_closed");
     if (!appPattern.test(appId)) throw new TypeError("appId must be 24 lowercase hexadecimal characters");
-    if (this.subscriptions.has(appId)) throw new TypeError("An app may only have one subscription per builder session");
+    if (this.subscriptions.has(appId)) throw new TypeError("An app may only have one subscription per chat session");
     if (this.subscriptions.size >= 8) throw new PlatformSocketError("subscription_limit", appId);
     const subscription = new Subscription(appId, { ...options }, () => {
       this.subscriptions.delete(appId);
diff --git a/packages/platform/src/client/modules/builder-subscription.ts b/packages/platform/src/client/modules/chat-subscription.ts
similarity index 94%
rename from packages/platform/src/client/modules/builder-subscription.ts
rename to packages/platform/src/client/modules/chat-subscription.ts
index 186ab251..dc4b46ff 100644
--- a/packages/platform/src/client/modules/builder-subscription.ts
+++ b/packages/platform/src/client/modules/chat-subscription.ts
@@ -1,7 +1,7 @@
-import type { PlatformEvent, PlatformSnapshot } from "./builder.events.types.js";
+import type { PlatformEvent, PlatformSnapshot } from "./chat.events.types.js";
 import { PlatformSocketError } from "../errors.js";
 import type { PlatformSocketErrorCode } from "../errors.types.js";
-import type { PlatformSubscription, SubscriptionOptions } from "./builder.types.js";
+import type { PlatformSubscription, SubscriptionOptions } from "./chat.types.js";
 
 /** @internal */
 export function notify(callback: (error: PlatformSocketError) => void, error: PlatformSocketError): void {
diff --git a/packages/platform/src/client/modules/builder.events.generated.ts b/packages/platform/src/client/modules/chat.events.generated.ts
similarity index 100%
rename from packages/platform/src/client/modules/builder.events.generated.ts
rename to packages/platform/src/client/modules/chat.events.generated.ts
diff --git a/packages/platform/src/client/modules/builder.events.types.ts b/packages/platform/src/client/modules/chat.events.types.ts
similarity index 98%
rename from packages/platform/src/client/modules/builder.events.types.ts
rename to packages/platform/src/client/modules/chat.events.types.ts
index 60294450..9833d7ae 100644
--- a/packages/platform/src/client/modules/builder.events.types.ts
+++ b/packages/platform/src/client/modules/chat.events.types.ts
@@ -1,4 +1,4 @@
-import type { Message, QueueState, ServerEventMap, Snapshot } from "./builder.events.generated.js";
+import type { Message, QueueState, ServerEventMap, Snapshot } from "./chat.events.generated.js";
 
 /**
  * Maps each live event name to the type of its `data` payload.
diff --git a/packages/platform/src/client/modules/chat.ts b/packages/platform/src/client/modules/chat.ts
new file mode 100644
index 00000000..3ef94f99
--- /dev/null
+++ b/packages/platform/src/client/modules/chat.ts
@@ -0,0 +1,9 @@
+import { ChatSocket } from "./chat-socket.js";
+import type { ChatModule } from "./chat.types.js";
+
+/** @internal */
+export function createChat(): ChatModule {
+  return {
+    init(options) { return new ChatSocket(options); },
+  };
+}
diff --git a/packages/platform/src/client/modules/builder.types.ts b/packages/platform/src/client/modules/chat.types.ts
similarity index 87%
rename from packages/platform/src/client/modules/builder.types.ts
rename to packages/platform/src/client/modules/chat.types.ts
index 064ab695..1f50702a 100644
--- a/packages/platform/src/client/modules/builder.types.ts
+++ b/packages/platform/src/client/modules/chat.types.ts
@@ -1,4 +1,4 @@
-import type { PlatformEvent, PlatformSnapshot } from "./builder.events.types.js";
+import type { PlatformEvent, PlatformSnapshot } from "./chat.events.types.js";
 import type { PlatformSocketError } from "../errors.js";
 
 /**
@@ -16,8 +16,8 @@ export interface SocketSession {
   socket_path: string;
 }
 
-/** Options for {@linkcode BuilderModule.init | init()}. */
-export interface BuilderInitOptions {
+/** Options for {@linkcode ChatModule.init | init()}. */
+export interface ChatInitOptions {
   /**
    * Returns a new socket session from your server.
    *
@@ -39,7 +39,7 @@ export interface BuilderInitOptions {
 }
 
 /**
- * Builder module for following the AI chat in your users' apps live.
+ * Chat module for following the AI chat in your users' apps live.
  *
  * Each session holds one socket and up to eight app subscriptions. For each app you get a
  * snapshot of its chat, then every change as it happens:
@@ -49,11 +49,11 @@ export interface BuilderInitOptions {
  *
  * The module does nothing until you call {@linkcode init | init()}.
  */
-export interface BuilderModule {
+export interface ChatModule {
   /**
-   * Creates a builder session without connecting it.
+   * Creates a chat session without connecting it.
    *
-   * Call {@linkcode BuilderSession.connect | connect()} on the returned session to open the socket.
+   * Call {@linkcode ChatSession.connect | connect()} on the returned session to open the socket.
    * Each session is independent, with its own socket, socket session and subscriptions.
    *
    * @param options - Session options.
@@ -62,26 +62,26 @@ export interface BuilderModule {
    * @example
    * ```typescript
    * // Create and connect a session
-   * const builder = client.builder.init({
+   * const chat = client.chat.init({
    *   async getSession() {
-   *     const response = await fetch('/api/builder-socket-session', { method: 'POST' });
+   *     const response = await fetch('/api/chat-socket-session', { method: 'POST' });
    *     return response.json();
    *   },
    *   onError(error) {
-   *     console.error('Builder session error', error.code);
+   *     console.error('Chat session error', error.code);
    *   },
    * });
-   * await builder.connect();
+   * await chat.connect();
    * ```
    */
-  init(options: BuilderInitOptions): BuilderSession;
+  init(options: ChatInitOptions): ChatSession;
 }
 
 /**
- * A `BuilderSession`: one socket with its app subscriptions and its reconnection. Use its methods
+ * A `ChatSession`: one socket with its app subscriptions and its reconnection. Use its methods
  * to connect, follow apps and close.
  */
-export interface BuilderSession {
+export interface ChatSession {
   /**
    * Connects the session's socket.
    *
@@ -98,7 +98,7 @@ export interface BuilderSession {
    * ```typescript
    * // Connect and handle failure
    * try {
-   *   await builder.connect();
+   *   await chat.connect();
    * } catch (error) {
    *   console.error('Could not connect', error.code);
    * }
@@ -125,7 +125,7 @@ export interface BuilderSession {
    * @example
    * ```typescript
    * // Follow an app
-   * const subscription = builder.subscribe(appId, {
+   * const subscription = chat.subscribe(appId, {
    *   onSnapshot(snapshot) {
    *     renderChat(snapshot.messages);
    *   },
@@ -143,13 +143,13 @@ export interface BuilderSession {
    * Closes the session.
    *
    * Ends every subscription, stops reconnecting and disconnects the socket. Calling it again does
-   * nothing. A closed session can't be reused, so call [`init()`](/developers/references/platform-sdk/docs/interfaces/builder#init)
+   * nothing. A closed session can't be reused, so call [`init()`](/developers/references/platform-sdk/docs/interfaces/chat#init)
    * for a new one.
    *
    * @example
    * ```typescript
    * // Close a session
-   * builder.close();
+   * chat.close();
    * ```
    */
   close(): void;
diff --git a/packages/platform/src/react/chat-items.ts b/packages/platform/src/react/chat-items.ts
index f827ec28..fc3d0da8 100644
--- a/packages/platform/src/react/chat-items.ts
+++ b/packages/platform/src/react/chat-items.ts
@@ -1,5 +1,5 @@
-import type { Message, QuestionArguments, QuestionInput, SetSecretsArguments } from "../client/modules/builder.events.generated.js";
-import type { ToolCall } from "../client/modules/builder.events.types.js";
+import type { Message, QuestionArguments, QuestionInput, SetSecretsArguments } from "../client/modules/chat.events.generated.js";
+import type { ToolCall } from "../client/modules/chat.events.types.js";
 import type { ApprovalDetails, ChatAnswer, ChatItem, ChatQuestion, ChatStep } from "./chat.types.js";
 
 /** @internal Sends the answer to the one tool call a question belongs to. */
@@ -40,7 +40,7 @@ function isTurnReply(message: Message | undefined): boolean {
   return message?.role === "assistant" && !message.additional_message_params?.skip_ai_response;
 }
 
-/** @internal The last assistant message that answers a turn, as Base44's own builder finds it. */
+/** @internal The last assistant message that answers a turn, as Base44's app editor finds it. */
 function lastTurnReply(sortedMessages: Message[]): Message | undefined {
   return [...sortedMessages].reverse().find(isTurnReply);
 }
@@ -120,7 +120,7 @@ export function stepStatus(toolCall: ToolCall): ChatStep["status"] {
   return "done";
 }
 
-/** @internal Whether the chat waits on the user. Like Base44's builder, only the last turn reply
+/** @internal Whether the chat waits on the user. Like Base44's app editor, only the last turn reply
  * counts, and a call answered or declined here stops counting. */
 export function isWaitingForUser(sortedMessages: Message[], answeredToolCallIds: string[]): boolean {
   const lastReply = lastTurnReply(sortedMessages);
@@ -180,7 +180,7 @@ export function pendingPromptItems(pendingPrompts: PendingPrompt[]): ChatItem[]
 
 /** @internal Base44's question formats, as one simple shape per kind, each bound to the call that
  * answers it. Base44 keys choice answers by position, so `picked` and `texts` follow `questions`,
- * and like Base44's builder a single pick goes in `selected_label`, several in `selected_labels`,
+ * and like Base44's app editor a single pick goes in `selected_label`, several in `selected_labels`,
  * and free text in `custom_text`. A kind this release doesn't know has no shape. */
 export function toQuestion(toolCall: ToolCall, answerToolCall: AnswerToolCall): ChatQuestion | undefined {
   const kind = toolCall.waiting_on?.kind;
diff --git a/packages/platform/src/react/chat.types.ts b/packages/platform/src/react/chat.types.ts
index 9c0eb515..3535a820 100644
--- a/packages/platform/src/react/chat.types.ts
+++ b/packages/platform/src/react/chat.types.ts
@@ -1,4 +1,4 @@
-import type { SocketSession } from "../client/modules/builder.types.js";
+import type { SocketSession } from "../client/modules/chat.types.js";
 
 /** An app the AI chat works on. */
 export interface Base44App {
diff --git a/packages/platform/src/react/index.ts b/packages/platform/src/react/index.ts
index 0841fdaf..346c91cb 100644
--- a/packages/platform/src/react/index.ts
+++ b/packages/platform/src/react/index.ts
@@ -4,4 +4,4 @@ export type {
   ApprovalDetails, ApprovalQuestion, Base44App, Base44Chat, Base44ChatOptions, Base44ChatBackend, ChatAnswer, ChatConnection, ChatError, ChatItem, ChatQuestion,
   ChatStatus, ChatStep, ChoiceEntry, ChoiceQuestion, SecretField, SecretsQuestion, ToolCallAnswer,
 } from "./chat.types.js";
-export type { SocketSession } from "../client/modules/builder.types.js";
+export type { SocketSession } from "../client/modules/chat.types.js";
diff --git a/packages/platform/src/react/useBase44Chat.ts b/packages/platform/src/react/useBase44Chat.ts
index fb95a437..b9ca6542 100644
--- a/packages/platform/src/react/useBase44Chat.ts
+++ b/packages/platform/src/react/useBase44Chat.ts
@@ -1,7 +1,7 @@
 "use client";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { createPlatformClient } from "../client/client.js";
-import type { Message, StatusObject } from "../client/modules/builder.events.generated.js";
+import type { Message, StatusObject } from "../client/modules/chat.events.generated.js";
 import { isWaitingForUser, mergeMessage, mergeSnapshot, pendingPromptItems, settlePendingPrompts, sortMessages, toItems, unknownKindToolCalls, waitingToolCallIds, type PendingPrompt } from "./chat-items.js";
 import type { Base44Chat, Base44ChatOptions, ChatConnection, ChatError, ChatStatus } from "./chat.types.js";
 
@@ -169,7 +169,7 @@ export function useBase44Chat({ appId, backend, onAppCreated }: Base44ChatOption
     // The client asks for a session on the first connect and whenever one expires, and forwards
     // no detail of a failed call, so the backend's own error is kept to report.
     let lastSessionError: unknown;
-    const builderSession = createPlatformClient().builder.init({
+    const chatSession = createPlatformClient().chat.init({
       getSession: () =>
         backendRef.current.openLiveSession(followedAppId).then(
           socketSession => {
@@ -188,7 +188,7 @@ export function useBase44Chat({ appId, backend, onAppCreated }: Base44ChatOption
         setConnection("disconnected");
       },
     });
-    builderSession.subscribe(followedAppId, {
+    chatSession.subscribe(followedAppId, {
       onSnapshot: snapshot => {
         // A snapshot holds old prompts too, so only an exact match settles one.
         handleIncomingMessages(snapshot.messages);
@@ -219,11 +219,11 @@ export function useBase44Chat({ appId, backend, onAppCreated }: Base44ChatOption
       onError: error => ((error as { code?: string }).code === "snapshot_unavailable" ? reportConnectionError(error) : endLiveUpdates(error)),
     });
     // A failed connect also reaches onError, which reports it.
-    builderSession.connect().catch(() => {});
+    chatSession.connect().catch(() => {});
 
     return () => {
       closed = true;
-      builderSession.close();
+      chatSession.close();
     };
   }, [currentAppId]);
 
diff --git a/packages/platform/src/server/modules/webhooks.events.generated.ts b/packages/platform/src/server/modules/webhooks.events.generated.ts
index 1ced2735..bde78fcb 100644
--- a/packages/platform/src/server/modules/webhooks.events.generated.ts
+++ b/packages/platform/src/server/modules/webhooks.events.generated.ts
@@ -141,10 +141,10 @@ export interface WebhookTestV1Data {
   challenge: string;
 }
 /**
- * Sent when the builder picks the message up, not when it is received: a
+ * Sent when the AI picks the message up, not when it is received: a
  * message sent while another turn runs waits in the queue until then.
  */
-export interface BuilderTurnStartedV1Data {
+export interface ChatTurnStartedV1Data {
   /**
    * The app the event is about.
    */
@@ -166,7 +166,7 @@ export interface BuilderTurnStartedV1Data {
    */
   conversation_id?: string;
   /**
-   * When the builder started working on the message (UTC).
+   * When the AI started working on the message (UTC).
    */
   started_at: string;
   /**
@@ -175,9 +175,9 @@ export interface BuilderTurnStartedV1Data {
   continues_message_id?: string;
 }
 /**
- * The `data` object of `builder.turn_ended.v1`. The builder finished responding to a message.
+ * The `data` object of `chat.turn_ended.v1`. The AI finished responding to a message.
  */
-export interface BuilderTurnEndedV1Data {
+export interface ChatTurnEndedV1Data {
   /**
    * The app the event is about.
    */
@@ -199,7 +199,7 @@ export interface BuilderTurnEndedV1Data {
    */
   conversation_id?: string;
   /**
-   * When the builder started working on the message (UTC).
+   * When the AI started working on the message (UTC).
    */
   started_at: string;
   /**
@@ -207,7 +207,7 @@ export interface BuilderTurnEndedV1Data {
    */
   continues_message_id?: string;
   /**
-   * How the turn ended. `finished`: the builder replied and has nothing pending. `waiting_for_user_input`: the builder stopped to ask something, such as a clarifying question or a plan to approve, and continues when the next message answers it. `failed`: the turn hit an error. `cancelled`: the turn was stopped before it ended. `interrupted`: the builder was interrupted, for example by a restart, and continues the work in a new turn whose `continues_message_id` is this message.
+   * How the turn ended. `finished`: the AI replied and has nothing pending. `waiting_for_user_input`: the AI stopped to ask something, such as a clarifying question or a plan to approve, and continues when the next message answers it. `failed`: the turn hit an error. `cancelled`: the turn was stopped before it ended. `interrupted`: the AI was interrupted, for example by a restart, and continues the work in a new turn whose `continues_message_id` is this message.
    */
   status: "finished" | "waiting_for_user_input" | "failed" | "cancelled" | "interrupted";
   /**
@@ -229,11 +229,11 @@ export interface WebhookEventMap {
   "app.restored.v1": AppRestoredV1Data;
   /** Carries no domain data — its only job is to be verifiable and echoed. */
   "webhook.test.v1": WebhookTestV1Data;
-  /** Sent when the builder picks the message up, not when it is received: a */
-  "builder.turn_started.v1": BuilderTurnStartedV1Data;
-  /** The builder finished responding to a message. */
-  "builder.turn_ended.v1": BuilderTurnEndedV1Data;
+  /** Sent when the AI picks the message up, not when it is received: a */
+  "chat.turn_started.v1": ChatTurnStartedV1Data;
+  /** The AI finished responding to a message. */
+  "chat.turn_ended.v1": ChatTurnEndedV1Data;
 }
 
 /** Every event type in {@link WebhookEventMap}, so events from a newer Base44 can be told apart at runtime. @internal */
-export const WEBHOOK_EVENT_TYPES = ["app.created.v1","app.published.v1","app.unpublished.v1","app.deleted.v1","app.restored.v1","webhook.test.v1","builder.turn_started.v1","builder.turn_ended.v1"] as const;
+export const WEBHOOK_EVENT_TYPES = ["app.created.v1","app.published.v1","app.unpublished.v1","app.deleted.v1","app.restored.v1","webhook.test.v1","chat.turn_started.v1","chat.turn_ended.v1"] as const;
diff --git a/packages/platform/tests/package.test.mjs b/packages/platform/tests/package.test.mjs
index 0f227c74..7de74df2 100644
--- a/packages/platform/tests/package.test.mjs
+++ b/packages/platform/tests/package.test.mjs
@@ -36,8 +36,8 @@ test("the client resolves from the installed package without the runtime SDK", (
     import assert from "node:assert/strict";
     import { createPlatformClient } from "@base44/platform";
     const client = createPlatformClient();
-    assert.equal(typeof client.builder.init, "function");
-    client.builder.init({ getSession: async () => ({ session_token: "t", socket_url: "https://example.test", socket_path: "/ws/socket.io/" }), onError() {} }).close();
+    assert.equal(typeof client.chat.init, "function");
+    client.chat.init({ getSession: async () => ({ session_token: "t", socket_url: "https://example.test", socket_path: "/ws/socket.io/" }), onError() {} }).close();
   `]);
 });
 
@@ -106,7 +106,7 @@ void useBase44Chat; void backend;
 
 import { createPlatformClient, type PlatformEvent } from "@base44/platform";
 const platform = createPlatformClient();
-platform.builder.init({ getSession: async () => (await fetch("/session")).json(), onError() {} }).subscribe("a".repeat(24), {
+platform.chat.init({ getSession: async () => (await fetch("/session")).json(), onError() {} }).subscribe("a".repeat(24), {
   onSnapshot(snapshot) { void snapshot.messages; },
   onEvent(event: PlatformEvent) {
     if (event.type === "message.updated") {
diff --git a/packages/platform/tests/types/client.types.ts b/packages/platform/tests/types/client.types.ts
index a16746b8..eac7d31e 100644
--- a/packages/platform/tests/types/client.types.ts
+++ b/packages/platform/tests/types/client.types.ts
@@ -1,20 +1,20 @@
 import { createPlatformClient, type SocketSession, type PlatformEvent, type PlatformEventMap, type PlatformSnapshot, type ToolCall, type GuardApproval, type Message, type StatusObject } from "@base44/platform";
 const client = createPlatformClient();
-const builder = client.builder.init({
+const chat = client.chat.init({
   // The Create socket session body passes through, extra keys included.
   getSession: async () => ({ session_id: "s1", session_token: "t", socket_url: "https://example.test", socket_path: "/ws/socket.io/", expires_in: 3600 }),
   onError: error => { void error.code; },
 });
-client.builder.init({ getSession: async () => (await fetch("/session")).json(), onError() {} });
+client.chat.init({ getSession: async () => (await fetch("/session")).json(), onError() {} });
 const body: SocketSession = { session_token: "t", socket_url: "https://example.test", socket_path: "/ws/socket.io/" };
 void body;
 // @ts-expect-error The session needs its socket path.
-client.builder.init({ getSession: async () => ({ session_token: "t", socket_url: "https://example.test" }), onError() {} });
+client.chat.init({ getSession: async () => ({ session_token: "t", socket_url: "https://example.test" }), onError() {} });
 // @ts-expect-error The session comes from init, not the client.
 createPlatformClient({ socketUrl: "https://example.test", getSessionToken: async () => "token" });
 // @ts-expect-error A session is required.
-client.builder.init({ onError() {} });
-const subscription = builder.subscribe("a".repeat(24), {
+client.chat.init({ onError() {} });
+const subscription = chat.subscribe("a".repeat(24), {
   onSnapshot(snapshot: PlatformSnapshot) {
     const state: "ready" | "processing" | "error" | null | undefined = snapshot.status?.state;
     const room: string = snapshot.room;
@@ -58,12 +58,14 @@ void subscription.active;
 // @ts-expect-error There is no replay cursor.
 void subscription.cursor;
 // @ts-expect-error Subscriptions take snapshots, not cursors.
-builder.subscribe("a".repeat(24), { afterSeq: "saved", onSnapshot() {}, onEvent() {}, onError() {} });
+chat.subscribe("a".repeat(24), { afterSeq: "saved", onSnapshot() {}, onEvent() {}, onError() {} });
 // @ts-expect-error No browser mutation channel.
 client.send("write_file", {});
 // @ts-expect-error API keys are not browser credentials.
 createPlatformClient({ apiKey: "private" });
-// @ts-expect-error Socket methods belong to the builder session.
+// @ts-expect-error The module is `chat`; `builder` was its name before 0.4.0.
+client.builder;
+// @ts-expect-error Socket methods belong to the chat session.
 client.connect();
 
 const tool: ToolCall = {
diff --git a/packages/platform/tests/unit/client.test.ts b/packages/platform/tests/unit/client.test.ts
index 6d884f6f..f2ae8e02 100644
--- a/packages/platform/tests/unit/client.test.ts
+++ b/packages/platform/tests/unit/client.test.ts
@@ -1,5 +1,5 @@
 import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";
-import { createPlatformClient, PlatformSocketError, type BuilderSession } from "../../src/client/index.js";
+import { createPlatformClient, PlatformSocketError, type ChatSession } from "../../src/client/index.js";
 
 const fake = vi.hoisted(() => {
   const handlers: Record<string, (...args: any[]) => void> = {};
@@ -16,7 +16,7 @@ const fake = vi.hoisted(() => {
 vi.mock("socket.io-client", () => ({ io: fake.io }));
 
 const app = "a".repeat(24), other = "b".repeat(24), room = `/apps/${app}`;
-const clients: BuilderSession[] = [];
+const clients: ChatSession[] = [];
 const settle = async () => { for (let i = 0; i < 100; i++) await Promise.resolve(); };
 const snapshot = (messages: unknown[] = []) => fake.handlers["app.snapshot"]({ room, data: { status: { state: "ready" }, messages } });
 const update = (data: unknown = { status: null }) => fake.handlers["app.status_changed"]({ room, data });
@@ -30,14 +30,14 @@ const auth = async () => {
 };
 function setup(getSession = vi.fn(async (): Promise<any> => session())) {
   const onError = vi.fn();
-  const client = createPlatformClient().builder.init({ getSession, onError });
+  const client = createPlatformClient().chat.init({ getSession, onError });
   clients.push(client);
   return { client, getSession, onError };
 }
-async function begin(client: BuilderSession) {
+async function begin(client: ChatSession) {
   client.connect().catch(() => {}); await settle();
 }
-async function connected(client: BuilderSession) {
+async function connected(client: ChatSession) {
   const ready = client.connect(); await settle(); fake.socket.connected = true; fake.handlers.connect(); await ready; await settle();
 }
 const joins = () => fake.socket.emit.mock.calls.filter(c => c[0] === "join");
@@ -48,15 +48,15 @@ describe("platform client", () => {
   test("creating the client and initializing sessions opens no socket and fetches no session", () => {
     const getSession = vi.fn(async () => session());
     const platform = createPlatformClient();
-    const first = platform.builder.init({ getSession, onError: vi.fn() });
-    const second = platform.builder.init({ getSession, onError: vi.fn() });
+    const first = platform.chat.init({ getSession, onError: vi.fn() });
+    const second = platform.chat.init({ getSession, onError: vi.fn() });
     clients.push(first, second);
     expect(first).not.toBe(second);
     expect(fake.io).not.toHaveBeenCalled();
     expect(getSession).not.toHaveBeenCalled();
   });
 
-  test("closing one initialized builder does not close another or the root module", async () => {
+  test("closing one initialized chat session does not close another or the root module", async () => {
     const firstSocket = { ...fake.socket, disconnect: vi.fn() };
     const secondSocket = { ...fake.socket, disconnect: vi.fn() };
     fake.io.mockReturnValueOnce(firstSocket).mockReturnValueOnce(secondSocket);
diff --git a/packages/platform/tests/unit/react/chat-items.test.ts b/packages/platform/tests/unit/react/chat-items.test.ts
index 49c40f1f..dd5e9631 100644
--- a/packages/platform/tests/unit/react/chat-items.test.ts
+++ b/packages/platform/tests/unit/react/chat-items.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test, vi } from "vitest";
-import type { Message } from "../../../src/client/modules/builder.events.generated.js";
-import type { ToolCall } from "../../../src/client/modules/builder.events.types.js";
+import type { Message } from "../../../src/client/modules/chat.events.generated.js";
+import type { ToolCall } from "../../../src/client/modules/chat.events.types.js";
 import { toQuestion, isWaitingForUser, mergeMessage, mergeSnapshot, pendingPromptItems, settlePendingPrompts, SNAPSHOT_SIZE, sortMessages, stepStatus, toItems, unknownKindToolCalls, waitingToolCallIds } from "../../../src/react/chat-items.js";
 
 const message = (id: string, created: string, extra: Partial<Message> = {}): Message => ({ id, role: "assistant", metadata: { created_date: created }, ...extra });
@@ -115,7 +115,7 @@ describe("items", () => {
     expect(waitingToolCallIds(sorted)).toEqual(new Set(["t0", "t1", "t2", "t3"]));
   });
 
-  test("the chat waits only on the last assistant message, as in Base44's builder", () => {
+  test("the chat waits only on the last assistant message, as in Base44's app editor", () => {
     const sorted = [message("m1", "1", { tool_calls: [{ id: "t0", status: "running" }] }), message("m2", "2", { tool_calls: [waiting("t1"), waiting("t2")] })];
     expect(isWaitingForUser(sorted, [])).toBe(true);
     expect(isWaitingForUser(sorted, ["t1"])).toBe(true);
@@ -206,7 +206,7 @@ describe("questions", () => {
       { text: "Extras?", description: undefined, type: undefined, options: ["X", "Y"], multi: true },
       { text: "Name it", description: undefined, type: "text_input", options: [], multi: false },
     ]);
-    // As in Base44's builder: one pick in selected_label, several in selected_labels.
+    // As in Base44's app editor: one pick in selected_label, several in selected_labels.
     await question.answer([["A"], ["X", "Y"]]);
     expect(reply).toHaveBeenCalledWith(true, {
       answers: [
diff --git a/packages/platform/tests/unit/react/useBase44Chat.test.ts b/packages/platform/tests/unit/react/useBase44Chat.test.ts
index 259afc9d..a7c65df9 100644
--- a/packages/platform/tests/unit/react/useBase44Chat.test.ts
+++ b/packages/platform/tests/unit/react/useBase44Chat.test.ts
@@ -2,9 +2,9 @@
 import { createElement, act } from "react";
 import { createRoot, type Root } from "react-dom/client";
 import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";
-import type { Message, QueueItem } from "../../../src/client/modules/builder.events.generated.js";
-import type { PlatformSnapshot } from "../../../src/client/modules/builder.events.types.js";
-import type { SocketSession } from "../../../src/client/modules/builder.types.js";
+import type { Message, QueueItem } from "../../../src/client/modules/chat.events.generated.js";
+import type { PlatformSnapshot } from "../../../src/client/modules/chat.events.types.js";
+import type { SocketSession } from "../../../src/client/modules/chat.types.js";
 import { useBase44Chat } from "../../../src/react/index.js";
 import type { Base44Chat, Base44ChatOptions, Base44ChatBackend } from "../../../src/react/index.js";
 
@@ -17,7 +17,7 @@ type FakeSession = { subs: Record<string, SubOptions>; init: InitOptions; closed
 const fake = vi.hoisted(() => ({ sessions: [] as FakeSession[] }));
 vi.mock("../../../src/client/client.js", () => ({
   createPlatformClient: () => ({
-    builder: {
+    chat: {
       init(init: InitOptions) {
         const session: FakeSession & { subscribe(appId: string, opts: SubOptions): unknown; close(): void } = {
           subs: {},
@@ -43,10 +43,10 @@ vi.mock("../../../src/client/client.js", () => ({
 }));
 vi.mock("../../../src/client.js", () => ({
   Base44PlatformClient: class {
-    builder: { init(options: InitOptions): FakeSession };
+    chat: { init(options: InitOptions): FakeSession };
     constructor(options: ClientOptions) {
       fake.clients.push(options);
-      this.builder = {
+      this.chat = {
         init(init) {
           const session: FakeSession & { subscribe(appId: string, opts: SubOptions): unknown; close(): void } = {
             subs: {},
diff --git a/packages/platform/tests/unit/socket.test.js b/packages/platform/tests/unit/socket.test.js
index b6b5accc..e9304ebb 100644
--- a/packages/platform/tests/unit/socket.test.js
+++ b/packages/platform/tests/unit/socket.test.js
@@ -30,7 +30,7 @@ test("real Socket.IO handshake, join, snapshot, reconnect and session renewal",
     });
   });
   await new Promise(resolve => http.listen(0, "127.0.0.1", resolve));
-  const builder = createPlatformClient().builder.init({
+  const chat = createPlatformClient().chat.init({
     getSession: async () => ({
       session_id: `id-${tokenCalls}`, session_token: `session-${++tokenCalls}`, expires_in: 3600,
       socket_url: `http://127.0.0.1:${http.address().port}`, socket_path: "/live/socket.io/",
@@ -38,8 +38,8 @@ test("real Socket.IO handshake, join, snapshot, reconnect and session renewal",
     onError: error => errors.push(error),
   });
   try {
-    builder.subscribe(appId, { onSnapshot: s => { snapshots.push(s.messages[0].id); }, onEvent: vi.fn(), onError: error => errors.push(error) });
-    await builder.connect();
+    chat.subscribe(appId, { onSnapshot: s => { snapshots.push(s.messages[0].id); }, onEvent: vi.fn(), onError: error => errors.push(error) });
+    await chat.connect();
     await vi.waitFor(() => expect(snapshots).toEqual(["m1"]));
     peers[0].terminate();
     await vi.waitFor(() => expect(snapshots).toEqual(["m1", "m2"]), { timeout: 6000 });
@@ -56,7 +56,7 @@ test("real Socket.IO handshake, join, snapshot, reconnect and session renewal",
     }
     expect(errors).toEqual([]);
   } finally {
-    builder.close();
+    chat.close();
     for (const peer of peers) peer.terminate();
     await new Promise(resolve => server.close(resolve));
     await new Promise(resolve => http.close(resolve));
diff --git a/packages/sdk/scripts/mintlify-post-processing/file-processing/file-processing.js b/packages/sdk/scripts/mintlify-post-processing/file-processing/file-processing.js
index 9f824775..b677e60a 100755
--- a/packages/sdk/scripts/mintlify-post-processing/file-processing/file-processing.js
+++ b/packages/sdk/scripts/mintlify-post-processing/file-processing/file-processing.js
@@ -2587,7 +2587,7 @@ function applyClassPageCleanup(dir) {
 }
 
 /**
- * A Returns type line such as `BuilderSession` becomes a link when the same page documents that type:
+ * A Returns type line such as `ChatSession` becomes a link when the same page documents that type:
  * its methods section (page-sections.json `typesWithOwnMethods`) or its own ### heading.
  */
 function linkReturnTypes(content) {