diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index de1434c..c501d33 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -4,11 +4,16 @@ on:
   pull_request:
     branches: [main]
 
+env:
+  TURBO_TELEMETRY_DISABLED: '1'
+
 jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
 
       - uses: pnpm/action-setup@v4
 
@@ -26,6 +31,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
 
       - uses: pnpm/action-setup@v4
 
@@ -43,6 +50,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
 
       - uses: pnpm/action-setup@v4
 
@@ -60,6 +69,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
 
       - uses: pnpm/action-setup@v4
 
diff --git a/.github/workflows/publish.yaml b/.github/workflows/publish.yaml
index 22a7a61..0927388 100644
--- a/.github/workflows/publish.yaml
+++ b/.github/workflows/publish.yaml
@@ -10,9 +10,11 @@ on:
         description: >
           Release mode:
           - "version" — Creates a "Version Packages" PR that bumps versions and
-            updates CHANGELOG.md based on pending changesets. Run this first.
-          - "publish" — Publishes the package to npm with provenance. Only run
-            this AFTER the Version Packages PR has been merged to main.
+            updates each package's CHANGELOG.md based on pending changesets. Run
+            this first.
+          - "publish" — Publishes every package whose on-disk version differs
+            from npm, with provenance. Only run this AFTER the Version Packages
+            PR has been merged to main.
           NOTE: @openrouter/agent releases must be coordinated with @openrouter/sdk
           because callModel changes are typically coupled with SDK type changes.
         required: true
@@ -23,8 +25,8 @@ on:
         default: version
       dry-run:
         description: >
-          Dry run: If enabled, simulates the release without making any changes.
-          Useful for verifying what would happen before committing to a release.
+          Dry run: If enabled, simulates the publish without making any changes.
+          Useful for verifying what would publish before committing to a release.
         required: false
         type: boolean
         default: false
@@ -34,6 +36,9 @@ permissions:
   pull-requests: write # For creating/updating the Version Packages PR
   id-token: write # For npm provenance signing
 
+env:
+  TURBO_TELEMETRY_DISABLED: '1'
+
 jobs:
   release:
     runs-on: ubuntu-latest
@@ -55,39 +60,33 @@ jobs:
 
       - run: pnpm run test
 
-      - name: Check for pending changesets
-        if: github.event_name == 'push'
-        id: changesets
-        run: |
-          if ls .changeset/*.md 1>/dev/null 2>&1; then
-            echo "pending=true" >> "$GITHUB_OUTPUT"
-          else
-            echo "pending=false" >> "$GITHUB_OUTPUT"
-          fi
-
-      - name: Create Version Packages PR
+      - name: Version PR or Publish (changesets)
         if: >
-          (github.event_name == 'push' && steps.changesets.outputs.pending == 'true') ||
+          github.event_name == 'push' ||
           (github.event_name == 'workflow_dispatch' && inputs.mode == 'version')
         uses: changesets/action@v1
         with:
-          title: "chore: version packages"
-          commit: "chore: version packages"
-          publish: pnpm publish --no-git-checks --provenance --access public
+          title: 'chore: version packages'
+          commit: 'chore: version packages'
+          version: pnpm exec changeset version
+          publish: pnpm exec changeset publish --no-git-checks
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
 
-      - name: Publish to npm
-        if: >
-          (github.event_name == 'push' && steps.changesets.outputs.pending == 'false') ||
-          (github.event_name == 'workflow_dispatch' && inputs.mode == 'publish' && !inputs.dry-run)
-        run: pnpm publish --no-git-checks --provenance --access public
+      - name: Publish (workflow_dispatch, live)
+        if: github.event_name == 'workflow_dispatch' && inputs.mode == 'publish' && !inputs.dry-run
+        run: pnpm exec changeset publish --no-git-checks
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
 
-      - name: Publish to npm (dry run)
+      # `changeset publish` has no native --dry-run. Fall back to pnpm's
+      # recursive dry-run, which simulates publishing every workspace package
+      # rather than only the ones changesets would pick. Output set may be
+      # wider than the live publish — but nothing is actually published, so
+      # this is only a diagnostic preview.
+      - name: Publish (workflow_dispatch, dry-run)
         if: github.event_name == 'workflow_dispatch' && inputs.mode == 'publish' && inputs.dry-run
-        run: pnpm publish --no-git-checks --provenance --access public --dry-run
+        run: pnpm -r publish --dry-run --access public --provenance --no-git-checks
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
diff --git a/.gitignore b/.gitignore
index 4764de2..71e06aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,8 @@
 esm/
 node_modules/
 .eslintcache
-.worktrees/
\ No newline at end of file
+.worktrees/
+.turbo/
+.env
+.env.*
+!.env.example
\ No newline at end of file
diff --git a/README.md b/README.md
index 7882384..a2d226b 100644
--- a/README.md
+++ b/README.md
@@ -1,367 +1,36 @@
-# OpenRouter Agent (Beta)
+# typescript-agent
 
-Agent toolkit for building AI applications with [OpenRouter](https://openrouter.ai) — tool orchestration, streaming, multi-turn conversations, and format compatibility.
+Monorepo for the OpenRouter TypeScript agent ecosystem.
 
-> [!IMPORTANT]
-> This SDK is currently in beta. There may be breaking changes between versions.
-> We recommend pinning to a specific version in your `package.json`.
+## Packages
 
-## Installation
-
-```bash
-# npm
-npm install @openrouter/agent
-
-# pnpm
-pnpm add @openrouter/agent
-
-# bun
-bun add @openrouter/agent
-
-# yarn
-yarn add @openrouter/agent
-```
-
-> [!NOTE]
-> This package is ESM-only. If you are using CommonJS, you can use `await import('@openrouter/agent')`.
-
-## Quick Start
-
-```typescript
-import OpenRouter from '@openrouter/sdk';
-import { callModel, tool } from '@openrouter/agent';
-import { z } from 'zod';
-
-const client = new OpenRouter({ apiKey: 'YOUR_API_KEY' });
-
-const weatherTool = tool({
-  name: 'get_weather',
-  description: 'Get the current weather for a location',
-  inputSchema: z.object({ location: z.string() }),
-  execute: async ({ location }) => ({
-    temperature: 72,
-    condition: 'sunny',
-    location,
-  }),
-});
-
-const result = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'What is the weather in San Francisco?',
-  tools: [weatherTool] as const,
-});
-
-// Get the final text response (tools are auto-executed)
-const text = await result.getText();
-console.log(text);
-```
-
-## Features
-
-### Multiple Response Consumption Patterns
-
-`callModel` returns a `ModelResult` that supports many ways to consume the response — all usable concurrently on the same result:
-
-```typescript
-const result = callModel(client, { model, input, tools });
-
-// Await the final text
-const text = await result.getText();
-
-// Await the full response with usage data
-const response = await result.getResponse();
-console.log(response.usage); // { inputTokens, outputTokens, cost, ... }
-
-// Stream text deltas
-for await (const delta of result.getTextStream()) {
-  process.stdout.write(delta);
-}
-
-// Stream reasoning deltas
-for await (const delta of result.getReasoningStream()) {
-  process.stdout.write(delta);
-}
-
-// Stream tool execution events
-for await (const event of result.getToolStream()) {
-  console.log(event);
-}
-
-// Stream structured tool calls
-for await (const toolCall of result.getToolCallsStream()) {
-  console.log(toolCall.name, toolCall.input);
-}
-
-// Get all tool calls after completion
-const toolCalls = await result.getToolCalls();
-```
-
-### Tool Types
-
-The `tool()` factory creates type-safe tools with full Zod schema inference. Three tool types are supported:
-
-**Regular tools** — automatically executed by the agent loop:
-
-```typescript
-const searchTool = tool({
-  name: 'search',
-  description: 'Search the web',
-  inputSchema: z.object({ query: z.string() }),
-  outputSchema: z.object({ results: z.array(z.string()) }),
-  execute: async ({ query }) => {
-    const results = await performSearch(query);
-    return { results };
-  },
-});
-```
-
-**Generator tools** — stream intermediate events during execution:
-
-```typescript
-const analysisTool = tool({
-  name: 'analyze',
-  inputSchema: z.object({ data: z.string() }),
-  eventSchema: z.object({ progress: z.number() }),
-  outputSchema: z.object({ summary: z.string() }),
-  execute: async function* ({ data }) {
-    yield { progress: 0.5 };
-    // ... processing ...
-    return { summary: 'Analysis complete' };
-  },
-});
-```
-
-**Manual tools** — reported to the model but not auto-executed (for human-in-the-loop flows):
-
-```typescript
-const confirmTool = tool({
-  name: 'confirm_action',
-  inputSchema: z.object({ action: z.string() }),
-  execute: false,
-});
-```
-
-### Stop Conditions
-
-Control when the agent loop stops executing tools:
-
-```typescript
-import { callModel, stepCountIs, hasToolCall, maxTokensUsed, maxCost } from '@openrouter/agent';
-
-const result = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'Research this topic thoroughly',
-  tools: [searchTool, summarizeTool] as const,
-  // Single condition
-  stopWhen: stepCountIs(10),
-  // Or combine multiple (stops when ANY condition is met)
-  stopWhen: [stepCountIs(10), maxCost(0.50), hasToolCall('summarize')],
-});
-```
-
-Built-in stop conditions:
-
-| Condition | Description |
-|---|---|
-| `stepCountIs(n)` | Stop after `n` tool execution steps (default: 5) |
-| `hasToolCall(name)` | Stop when a specific tool is called |
-| `maxTokensUsed(n)` | Stop when total tokens exceed a threshold |
-| `maxCost(dollars)` | Stop when total cost exceeds a dollar amount |
-| `finishReasonIs(reason)` | Stop on a specific finish reason |
-
-### Tool Approval
-
-Gate tool execution with approval checks for sensitive operations:
-
-```typescript
-const deleteTool = tool({
-  name: 'delete_record',
-  inputSchema: z.object({ id: z.string() }),
-  requireApproval: true, // Always require approval
-  execute: async ({ id }) => { /* ... */ },
-});
-
-// Or use a function for conditional approval
-const writeTool = tool({
-  name: 'write_file',
-  inputSchema: z.object({ path: z.string(), content: z.string() }),
-  requireApproval: ({ path }) => path.startsWith('/etc'),
-  execute: async ({ path, content }) => { /* ... */ },
-});
-
-// Handle approvals at the callModel level
-const result = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'Delete record abc-123',
-  tools: [deleteTool] as const,
-  approveToolCalls: async (toolCalls) => {
-    // Return IDs of approved tool calls
-    return toolCalls.map(tc => tc.id);
-  },
-});
-```
-
-### Tool Context
-
-Provide typed context data to tools without passing it through the model:
-
-```typescript
-const dbTool = tool({
-  name: 'query_db',
-  inputSchema: z.object({ sql: z.string() }),
-  contextSchema: z.object({ connectionString: z.string() }),
-  execute: async ({ sql }, ctx) => {
-    const db = connect(ctx?.context.connectionString);
-    return db.query(sql);
-  },
-});
-
-const result = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'List all users',
-  tools: [dbTool] as const,
-  context: {
-    query_db: { connectionString: 'postgres://localhost/mydb' },
-  },
-});
-```
-
-### Shared Context
-
-Share mutable state across all tools in a conversation:
-
-```typescript
-const result = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'Process these items',
-  tools: [toolA, toolB] as const,
-  sharedContextSchema: z.object({ processedIds: z.array(z.string()) }),
-  context: {
-    shared: { processedIds: [] },
-  },
-});
-```
-
-### Conversation State Management
-
-Persist multi-turn conversations with full state tracking:
-
-```typescript
-import { createInitialState, callModel } from '@openrouter/agent';
-
-// Start a conversation
-let state = createInitialState();
-
-// First turn
-const result1 = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'Search for TypeScript best practices',
-  tools: [searchTool] as const,
-  state,
-});
-
-// State is updated with messages, tool calls, and metadata
-state = (await result1.getResponse()).state;
-
-// Continue the conversation
-const result2 = callModel(client, {
-  model: 'openai/gpt-4o',
-  input: 'Now summarize what you found',
-  tools: [searchTool] as const,
-  state,
-});
-```
-
-### Dynamic Parameters Between Turns
-
-Adjust model parameters dynamically based on tool execution:
-
-```typescript
-const searchTool = tool({
-  name: 'search',
-  inputSchema: z.object({ query: z.string() }),
-  nextTurnParams: {
-    temperature: (input) => input.query.includes('creative') ? 0.9 : 0.1,
-    maxOutputTokens: () => 2000,
-  },
-  execute: async ({ query }) => { /* ... */ },
-});
-```
-
-### Format Compatibility
-
-Convert between OpenRouter and other message formats:
-
-```typescript
-import { toClaudeMessage, fromClaudeMessages } from '@openrouter/agent';
-import { toChatMessage, fromChatMessages } from '@openrouter/agent';
-
-// Anthropic Claude format
-const claudeMsg = toClaudeMessage(openRouterMessage);
-const orMessages = fromClaudeMessages(claudeMessages);
-
-// Standard Chat format
-const chatMsg = toChatMessage(openRouterMessage);
-const orMessages2 = fromChatMessages(chatMessages);
-```
-
-## Subpath Exports
-
-For tree-shaking or targeted imports, the package provides granular subpath exports:
-
-```typescript
-import { callModel } from '@openrouter/agent/call-model';
-import { tool } from '@openrouter/agent/tool';
-import { ModelResult } from '@openrouter/agent/model-result';
-import { stepCountIs, maxCost } from '@openrouter/agent/stop-conditions';
-import { toClaudeMessage } from '@openrouter/agent/anthropic-compat';
-import { toChatMessage } from '@openrouter/agent/chat-compat';
-import { ToolContextStore } from '@openrouter/agent/tool-context';
-import { ToolEventBroadcaster } from '@openrouter/agent/tool-event-broadcaster';
-import { createInitialState } from '@openrouter/agent/conversation-state';
-```
+| Package | Path | Description |
+| --- | --- | --- |
+| [`@openrouter/agent`](./packages/agent) | `packages/agent` | Agent toolkit for building AI applications with OpenRouter — tool orchestration, streaming, multi-turn conversations, and format compatibility. |
 
 ## Development
 
-```bash
-# Install dependencies
-pnpm install
-
-# Build
-pnpm build
-
-# Run unit tests
-pnpm test
-
-# Run end-to-end tests (requires OPENROUTER_API_KEY in .env)
-pnpm test:e2e
-
-# Type check
-pnpm typecheck
+This repo uses [pnpm workspaces](https://pnpm.io/workspaces) and [Turborepo](https://turbo.build/) for task orchestration.
 
-# Lint
-pnpm lint
+```bash
+pnpm install          # install all workspace dependencies
+pnpm run lint         # Biome check across all packages
+pnpm run typecheck    # TypeScript noEmit across all packages
+pnpm run build        # tsc across all packages
+pnpm run test         # vitest unit projects across all packages
+pnpm run test:e2e     # vitest e2e projects (requires OPENROUTER_API_KEY)
 ```
 
-### Running Tests
-
-Create a `.env` file with your OpenRouter API key:
+Turbo caches task results; re-running an unchanged task replays cached output.
 
-```env
-OPENROUTER_API_KEY=sk-or-...
-```
+## Releasing
 
-Then run:
+Releases are driven by [Changesets](https://github.com/changesets/changesets). Each PR that ships a user-visible change should include a changeset:
 
 ```bash
-pnpm test        # Unit tests
-pnpm test:e2e    # Integration tests (requires API key)
+pnpm changeset
 ```
 
-## Documentation
-
-Full `callModel` documentation is available at [openrouter.ai/docs/sdks/typescript/call-model](https://openrouter.ai/docs/sdks/typescript/call-model/overview).
-
-## License
+Pick the affected packages and bump type. On merge to `main`, the release workflow opens a "Version Packages" PR. Merging that PR publishes every package with a consumed changeset to npm — no republishing of unchanged packages.
 
-Apache-2.0
+See [`.github/workflows/publish.yaml`](./.github/workflows/publish.yaml) for the full flow.
diff --git a/biome.json b/biome.json
index 2d7c7af..0cc250e 100644
--- a/biome.json
+++ b/biome.json
@@ -17,7 +17,10 @@
       "**",
       "!**/*.json",
       "!!**/biome.json",
-      "!esm/**"
+      "!**/esm/**",
+      "!**/dist/**",
+      "!**/node_modules/**",
+      "!**/.worktrees/**"
     ]
   },
   "formatter": {
@@ -117,7 +120,7 @@
   "overrides": [
     {
       "includes": [
-        "tests/**",
+        "**/tests/**",
         "**/*.test.ts",
         "**/*.spec.ts"
       ],
diff --git a/package.json b/package.json
index 2385261..de7179c 100644
--- a/package.json
+++ b/package.json
@@ -1,122 +1,19 @@
 {
-  "name": "@openrouter/agent",
-  "version": "0.4.0",
-  "author": "OpenRouter",
-  "description": "Agent toolkit for building AI applications with OpenRouter — tool orchestration, streaming, multi-turn conversations, and format compatibility.",
-  "keywords": [
-    "openrouter",
-    "agent",
-    "typescript",
-    "ai",
-    "tools",
-    "streaming",
-    "llm"
-  ],
-  "license": "Apache-2.0",
+  "name": "typescript-agent-monorepo",
+  "private": true,
+  "version": "0.0.0",
   "packageManager": "pnpm@10.22.0",
-  "type": "module",
-  "main": "./esm/index.js",
-  "exports": {
-    ".": {
-      "types": "./esm/index.d.ts",
-      "default": "./esm/index.js"
-    },
-    "./call-model": {
-      "types": "./esm/inner-loop/call-model.d.ts",
-      "default": "./esm/inner-loop/call-model.js"
-    },
-    "./tool-types": {
-      "types": "./esm/lib/tool-types.d.ts",
-      "default": "./esm/lib/tool-types.js"
-    },
-    "./model-result": {
-      "types": "./esm/lib/model-result.d.ts",
-      "default": "./esm/lib/model-result.js"
-    },
-    "./async-params": {
-      "types": "./esm/lib/async-params.d.ts",
-      "default": "./esm/lib/async-params.js"
-    },
-    "./stop-conditions": {
-      "types": "./esm/lib/stop-conditions.d.ts",
-      "default": "./esm/lib/stop-conditions.js"
-    },
-    "./tool": {
-      "types": "./esm/lib/tool.d.ts",
-      "default": "./esm/lib/tool.js"
-    },
-    "./anthropic-compat": {
-      "types": "./esm/lib/anthropic-compat.d.ts",
-      "default": "./esm/lib/anthropic-compat.js"
-    },
-    "./chat-compat": {
-      "types": "./esm/lib/chat-compat.d.ts",
-      "default": "./esm/lib/chat-compat.js"
-    },
-    "./claude-constants": {
-      "types": "./esm/lib/claude-constants.d.ts",
-      "default": "./esm/lib/claude-constants.js"
-    },
-    "./claude-type-guards": {
-      "types": "./esm/lib/claude-type-guards.d.ts",
-      "default": "./esm/lib/claude-type-guards.js"
-    },
-    "./conversation-state": {
-      "types": "./esm/lib/conversation-state.d.ts",
-      "default": "./esm/lib/conversation-state.js"
-    },
-    "./next-turn-params": {
-      "types": "./esm/lib/next-turn-params.d.ts",
-      "default": "./esm/lib/next-turn-params.js"
-    },
-    "./stream-transformers": {
-      "types": "./esm/lib/stream-transformers.d.ts",
-      "default": "./esm/lib/stream-transformers.js"
-    },
-    "./tool-context": {
-      "types": "./esm/lib/tool-context.d.ts",
-      "default": "./esm/lib/tool-context.js"
-    },
-    "./tool-event-broadcaster": {
-      "types": "./esm/lib/tool-event-broadcaster.d.ts",
-      "default": "./esm/lib/tool-event-broadcaster.js"
-    },
-    "./turn-context": {
-      "types": "./esm/lib/turn-context.d.ts",
-      "default": "./esm/lib/turn-context.js"
-    },
-    "./openrouter": {
-      "types": "./esm/openrouter.d.ts",
-      "default": "./esm/openrouter.js"
-    },
-    "./package.json": "./package.json"
-  },
-  "sideEffects": false,
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/OpenRouterTeam/typescript-agent.git"
-  },
-  "files": [
-    "esm",
-    "package.json",
-    "README.md",
-    "LICENSE"
-  ],
   "scripts": {
-    "lint": "biome check src tests",
-    "lint:fix": "biome check --write src tests",
-    "build": "tsc",
-    "test": "vitest --run --project unit",
-    "test:e2e": "vitest --run --project e2e",
-    "test:watch": "vitest --watch --project unit",
-    "typecheck": "tsc --noEmit",
-    "compile": "tsc",
+    "build": "turbo run build",
+    "test": "turbo run test",
+    "test:e2e": "turbo run test:e2e",
+    "test:watch": "turbo run test:watch",
+    "lint": "turbo run lint",
+    "lint:fix": "biome check --write packages/*/src packages/*/tests",
+    "typecheck": "turbo run typecheck",
+    "changeset": "changeset",
     "prepare": "husky"
   },
-  "dependencies": {
-    "@openrouter/sdk": "^0.12.12",
-    "zod": "^4.0.0"
-  },
   "devDependencies": {
     "@biomejs/biome": "^2.4.10",
     "@changesets/changelog-github": "^0.6.0",
@@ -124,13 +21,8 @@
     "@types/node": "^22.13.12",
     "dotenv": "^16.4.7",
     "husky": "^9.1.7",
+    "turbo": "2.9.6",
     "typescript": "~5.8.3",
     "vitest": "^3.2.4"
-  },
-  "pnpm": {
-    "onlyBuiltDependencies": [
-      "@openrouter/sdk",
-      "esbuild"
-    ]
   }
 }
diff --git a/.npmignore b/packages/agent/.npmignore
similarity index 54%
rename from .npmignore
rename to packages/agent/.npmignore
index a8b3a8f..61f4b61 100644
--- a/.npmignore
+++ b/packages/agent/.npmignore
@@ -2,13 +2,7 @@
 ./tests
 ./vitest.config.ts
 ./tsconfig.json
-.github
-.changeset
 .env
 .env.*
 .gitignore
 .npmignore
-.prettierignore
-.prettierrc
-.prettierignore
-.grit/
\ No newline at end of file
diff --git a/CHANGELOG.md b/packages/agent/CHANGELOG.md
similarity index 100%
rename from CHANGELOG.md
rename to packages/agent/CHANGELOG.md
diff --git a/packages/agent/README.md b/packages/agent/README.md
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index 0000000..7882384
--- /dev/null
+++ b/packages/agent/README.md
@@ -0,0 +1,367 @@
+# OpenRouter Agent (Beta)
+
+Agent toolkit for building AI applications with [OpenRouter](https://openrouter.ai) — tool orchestration, streaming, multi-turn conversations, and format compatibility.
+
+> [!IMPORTANT]
+> This SDK is currently in beta. There may be breaking changes between versions.
+> We recommend pinning to a specific version in your `package.json`.
+
+## Installation
+
+```bash
+# npm
+npm install @openrouter/agent
+
+# pnpm
+pnpm add @openrouter/agent
+
+# bun
+bun add @openrouter/agent
+
+# yarn
+yarn add @openrouter/agent
+```
+
+> [!NOTE]
+> This package is ESM-only. If you are using CommonJS, you can use `await import('@openrouter/agent')`.
+
+## Quick Start
+
+```typescript
+import OpenRouter from '@openrouter/sdk';
+import { callModel, tool } from '@openrouter/agent';
+import { z } from 'zod';
+
+const client = new OpenRouter({ apiKey: 'YOUR_API_KEY' });
+
+const weatherTool = tool({
+  name: 'get_weather',
+  description: 'Get the current weather for a location',
+  inputSchema: z.object({ location: z.string() }),
+  execute: async ({ location }) => ({
+    temperature: 72,
+    condition: 'sunny',
+    location,
+  }),
+});
+
+const result = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'What is the weather in San Francisco?',
+  tools: [weatherTool] as const,
+});
+
+// Get the final text response (tools are auto-executed)
+const text = await result.getText();
+console.log(text);
+```
+
+## Features
+
+### Multiple Response Consumption Patterns
+
+`callModel` returns a `ModelResult` that supports many ways to consume the response — all usable concurrently on the same result:
+
+```typescript
+const result = callModel(client, { model, input, tools });
+
+// Await the final text
+const text = await result.getText();
+
+// Await the full response with usage data
+const response = await result.getResponse();
+console.log(response.usage); // { inputTokens, outputTokens, cost, ... }
+
+// Stream text deltas
+for await (const delta of result.getTextStream()) {
+  process.stdout.write(delta);
+}
+
+// Stream reasoning deltas
+for await (const delta of result.getReasoningStream()) {
+  process.stdout.write(delta);
+}
+
+// Stream tool execution events
+for await (const event of result.getToolStream()) {
+  console.log(event);
+}
+
+// Stream structured tool calls
+for await (const toolCall of result.getToolCallsStream()) {
+  console.log(toolCall.name, toolCall.input);
+}
+
+// Get all tool calls after completion
+const toolCalls = await result.getToolCalls();
+```
+
+### Tool Types
+
+The `tool()` factory creates type-safe tools with full Zod schema inference. Three tool types are supported:
+
+**Regular tools** — automatically executed by the agent loop:
+
+```typescript
+const searchTool = tool({
+  name: 'search',
+  description: 'Search the web',
+  inputSchema: z.object({ query: z.string() }),
+  outputSchema: z.object({ results: z.array(z.string()) }),
+  execute: async ({ query }) => {
+    const results = await performSearch(query);
+    return { results };
+  },
+});
+```
+
+**Generator tools** — stream intermediate events during execution:
+
+```typescript
+const analysisTool = tool({
+  name: 'analyze',
+  inputSchema: z.object({ data: z.string() }),
+  eventSchema: z.object({ progress: z.number() }),
+  outputSchema: z.object({ summary: z.string() }),
+  execute: async function* ({ data }) {
+    yield { progress: 0.5 };
+    // ... processing ...
+    return { summary: 'Analysis complete' };
+  },
+});
+```
+
+**Manual tools** — reported to the model but not auto-executed (for human-in-the-loop flows):
+
+```typescript
+const confirmTool = tool({
+  name: 'confirm_action',
+  inputSchema: z.object({ action: z.string() }),
+  execute: false,
+});
+```
+
+### Stop Conditions
+
+Control when the agent loop stops executing tools:
+
+```typescript
+import { callModel, stepCountIs, hasToolCall, maxTokensUsed, maxCost } from '@openrouter/agent';
+
+const result = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'Research this topic thoroughly',
+  tools: [searchTool, summarizeTool] as const,
+  // Single condition
+  stopWhen: stepCountIs(10),
+  // Or combine multiple (stops when ANY condition is met)
+  stopWhen: [stepCountIs(10), maxCost(0.50), hasToolCall('summarize')],
+});
+```
+
+Built-in stop conditions:
+
+| Condition | Description |
+|---|---|
+| `stepCountIs(n)` | Stop after `n` tool execution steps (default: 5) |
+| `hasToolCall(name)` | Stop when a specific tool is called |
+| `maxTokensUsed(n)` | Stop when total tokens exceed a threshold |
+| `maxCost(dollars)` | Stop when total cost exceeds a dollar amount |
+| `finishReasonIs(reason)` | Stop on a specific finish reason |
+
+### Tool Approval
+
+Gate tool execution with approval checks for sensitive operations:
+
+```typescript
+const deleteTool = tool({
+  name: 'delete_record',
+  inputSchema: z.object({ id: z.string() }),
+  requireApproval: true, // Always require approval
+  execute: async ({ id }) => { /* ... */ },
+});
+
+// Or use a function for conditional approval
+const writeTool = tool({
+  name: 'write_file',
+  inputSchema: z.object({ path: z.string(), content: z.string() }),
+  requireApproval: ({ path }) => path.startsWith('/etc'),
+  execute: async ({ path, content }) => { /* ... */ },
+});
+
+// Handle approvals at the callModel level
+const result = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'Delete record abc-123',
+  tools: [deleteTool] as const,
+  approveToolCalls: async (toolCalls) => {
+    // Return IDs of approved tool calls
+    return toolCalls.map(tc => tc.id);
+  },
+});
+```
+
+### Tool Context
+
+Provide typed context data to tools without passing it through the model:
+
+```typescript
+const dbTool = tool({
+  name: 'query_db',
+  inputSchema: z.object({ sql: z.string() }),
+  contextSchema: z.object({ connectionString: z.string() }),
+  execute: async ({ sql }, ctx) => {
+    const db = connect(ctx?.context.connectionString);
+    return db.query(sql);
+  },
+});
+
+const result = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'List all users',
+  tools: [dbTool] as const,
+  context: {
+    query_db: { connectionString: 'postgres://localhost/mydb' },
+  },
+});
+```
+
+### Shared Context
+
+Share mutable state across all tools in a conversation:
+
+```typescript
+const result = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'Process these items',
+  tools: [toolA, toolB] as const,
+  sharedContextSchema: z.object({ processedIds: z.array(z.string()) }),
+  context: {
+    shared: { processedIds: [] },
+  },
+});
+```
+
+### Conversation State Management
+
+Persist multi-turn conversations with full state tracking:
+
+```typescript
+import { createInitialState, callModel } from '@openrouter/agent';
+
+// Start a conversation
+let state = createInitialState();
+
+// First turn
+const result1 = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'Search for TypeScript best practices',
+  tools: [searchTool] as const,
+  state,
+});
+
+// State is updated with messages, tool calls, and metadata
+state = (await result1.getResponse()).state;
+
+// Continue the conversation
+const result2 = callModel(client, {
+  model: 'openai/gpt-4o',
+  input: 'Now summarize what you found',
+  tools: [searchTool] as const,
+  state,
+});
+```
+
+### Dynamic Parameters Between Turns
+
+Adjust model parameters dynamically based on tool execution:
+
+```typescript
+const searchTool = tool({
+  name: 'search',
+  inputSchema: z.object({ query: z.string() }),
+  nextTurnParams: {
+    temperature: (input) => input.query.includes('creative') ? 0.9 : 0.1,
+    maxOutputTokens: () => 2000,
+  },
+  execute: async ({ query }) => { /* ... */ },
+});
+```
+
+### Format Compatibility
+
+Convert between OpenRouter and other message formats:
+
+```typescript
+import { toClaudeMessage, fromClaudeMessages } from '@openrouter/agent';
+import { toChatMessage, fromChatMessages } from '@openrouter/agent';
+
+// Anthropic Claude format
+const claudeMsg = toClaudeMessage(openRouterMessage);
+const orMessages = fromClaudeMessages(claudeMessages);
+
+// Standard Chat format
+const chatMsg = toChatMessage(openRouterMessage);
+const orMessages2 = fromChatMessages(chatMessages);
+```
+
+## Subpath Exports
+
+For tree-shaking or targeted imports, the package provides granular subpath exports:
+
+```typescript
+import { callModel } from '@openrouter/agent/call-model';
+import { tool } from '@openrouter/agent/tool';
+import { ModelResult } from '@openrouter/agent/model-result';
+import { stepCountIs, maxCost } from '@openrouter/agent/stop-conditions';
+import { toClaudeMessage } from '@openrouter/agent/anthropic-compat';
+import { toChatMessage } from '@openrouter/agent/chat-compat';
+import { ToolContextStore } from '@openrouter/agent/tool-context';
+import { ToolEventBroadcaster } from '@openrouter/agent/tool-event-broadcaster';
+import { createInitialState } from '@openrouter/agent/conversation-state';
+```
+
+## Development
+
+```bash
+# Install dependencies
+pnpm install
+
+# Build
+pnpm build
+
+# Run unit tests
+pnpm test
+
+# Run end-to-end tests (requires OPENROUTER_API_KEY in .env)
+pnpm test:e2e
+
+# Type check
+pnpm typecheck
+
+# Lint
+pnpm lint
+```
+
+### Running Tests
+
+Create a `.env` file with your OpenRouter API key:
+
+```env
+OPENROUTER_API_KEY=sk-or-...
+```
+
+Then run:
+
+```bash
+pnpm test        # Unit tests
+pnpm test:e2e    # Integration tests (requires API key)
+```
+
+## Documentation
+
+Full `callModel` documentation is available at [openrouter.ai/docs/sdks/typescript/call-model](https://openrouter.ai/docs/sdks/typescript/call-model/overview).
+
+## License
+
+Apache-2.0
diff --git a/packages/agent/package.json b/packages/agent/package.json
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@@ -0,0 +1,122 @@
+{
+  "name": "@openrouter/agent",
+  "version": "0.4.0",
+  "author": "OpenRouter",
+  "description": "Agent toolkit for building AI applications with OpenRouter — tool orchestration, streaming, multi-turn conversations, and format compatibility.",
+  "keywords": [
+    "openrouter",
+    "agent",
+    "typescript",
+    "ai",
+    "tools",
+    "streaming",
+    "llm"
+  ],
+  "license": "Apache-2.0",
+  "type": "module",
+  "main": "./esm/index.js",
+  "exports": {
+    ".": {
+      "types": "./esm/index.d.ts",
+      "default": "./esm/index.js"
+    },
+    "./call-model": {
+      "types": "./esm/inner-loop/call-model.d.ts",
+      "default": "./esm/inner-loop/call-model.js"
+    },
+    "./tool-types": {
+      "types": "./esm/lib/tool-types.d.ts",
+      "default": "./esm/lib/tool-types.js"
+    },
+    "./model-result": {
+      "types": "./esm/lib/model-result.d.ts",
+      "default": "./esm/lib/model-result.js"
+    },
+    "./async-params": {
+      "types": "./esm/lib/async-params.d.ts",
+      "default": "./esm/lib/async-params.js"
+    },
+    "./stop-conditions": {
+      "types": "./esm/lib/stop-conditions.d.ts",
+      "default": "./esm/lib/stop-conditions.js"
+    },
+    "./tool": {
+      "types": "./esm/lib/tool.d.ts",
+      "default": "./esm/lib/tool.js"
+    },
+    "./anthropic-compat": {
+      "types": "./esm/lib/anthropic-compat.d.ts",
+      "default": "./esm/lib/anthropic-compat.js"
+    },
+    "./chat-compat": {
+      "types": "./esm/lib/chat-compat.d.ts",
+      "default": "./esm/lib/chat-compat.js"
+    },
+    "./claude-constants": {
+      "types": "./esm/lib/claude-constants.d.ts",
+      "default": "./esm/lib/claude-constants.js"
+    },
+    "./claude-type-guards": {
+      "types": "./esm/lib/claude-type-guards.d.ts",
+      "default": "./esm/lib/claude-type-guards.js"
+    },
+    "./conversation-state": {
+      "types": "./esm/lib/conversation-state.d.ts",
+      "default": "./esm/lib/conversation-state.js"
+    },
+    "./next-turn-params": {
+      "types": "./esm/lib/next-turn-params.d.ts",
+      "default": "./esm/lib/next-turn-params.js"
+    },
+    "./stream-transformers": {
+      "types": "./esm/lib/stream-transformers.d.ts",
+      "default": "./esm/lib/stream-transformers.js"
+    },
+    "./tool-context": {
+      "types": "./esm/lib/tool-context.d.ts",
+      "default": "./esm/lib/tool-context.js"
+    },
+    "./tool-event-broadcaster": {
+      "types": "./esm/lib/tool-event-broadcaster.d.ts",
+      "default": "./esm/lib/tool-event-broadcaster.js"
+    },
+    "./turn-context": {
+      "types": "./esm/lib/turn-context.d.ts",
+      "default": "./esm/lib/turn-context.js"
+    },
+    "./openrouter": {
+      "types": "./esm/openrouter.d.ts",
+      "default": "./esm/openrouter.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "sideEffects": false,
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/OpenRouterTeam/typescript-agent.git",
+    "directory": "packages/agent"
+  },
+  "publishConfig": {
+    "access": "public",
+    "provenance": true
+  },
+  "files": [
+    "esm",
+    "package.json",
+    "README.md"
+  ],
+  "scripts": {
+    "lint": "biome check src tests",
+    "lint:fix": "biome check --write src tests",
+    "build": "tsc",
+    "test": "vitest --run --project unit",
+    "test:e2e": "vitest --run --project e2e",
+    "test:watch": "vitest --watch --project unit",
+    "typecheck": "tsc --noEmit",
+    "compile": "tsc"
+  },
+  "dependencies": {
+    "@openrouter/sdk": "^0.12.12",
+    "zod": "^4.0.0"
+  }
+}
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rename from tests/unit/create-tool.test.ts
rename to packages/agent/tests/unit/create-tool.test.ts
diff --git a/tests/unit/get-items-stream-manual-tools.test.ts b/packages/agent/tests/unit/get-items-stream-manual-tools.test.ts
similarity index 100%
rename from tests/unit/get-items-stream-manual-tools.test.ts
rename to packages/agent/tests/unit/get-items-stream-manual-tools.test.ts
diff --git a/tests/unit/has-approval-tools.test-d.ts b/packages/agent/tests/unit/has-approval-tools.test-d.ts
similarity index 100%
rename from tests/unit/has-approval-tools.test-d.ts
rename to packages/agent/tests/unit/has-approval-tools.test-d.ts
diff --git a/tests/unit/manual-tool-calls-adversarial.test.ts b/packages/agent/tests/unit/manual-tool-calls-adversarial.test.ts
similarity index 100%
rename from tests/unit/manual-tool-calls-adversarial.test.ts
rename to packages/agent/tests/unit/manual-tool-calls-adversarial.test.ts
diff --git a/tests/unit/openrouter.test.ts b/packages/agent/tests/unit/openrouter.test.ts
similarity index 100%
rename from tests/unit/openrouter.test.ts
rename to packages/agent/tests/unit/openrouter.test.ts
diff --git a/tests/unit/schema-sanitization.test.ts b/packages/agent/tests/unit/schema-sanitization.test.ts
similarity index 100%
rename from tests/unit/schema-sanitization.test.ts
rename to packages/agent/tests/unit/schema-sanitization.test.ts
diff --git a/tests/unit/server-tool-stream-narrowing.test-d.ts b/packages/agent/tests/unit/server-tool-stream-narrowing.test-d.ts
similarity index 100%
rename from tests/unit/server-tool-stream-narrowing.test-d.ts
rename to packages/agent/tests/unit/server-tool-stream-narrowing.test-d.ts
diff --git a/tests/unit/server-tool.test.ts b/packages/agent/tests/unit/server-tool.test.ts
similarity index 100%
rename from tests/unit/server-tool.test.ts
rename to packages/agent/tests/unit/server-tool.test.ts
diff --git a/tests/unit/shared-context.test.ts b/packages/agent/tests/unit/shared-context.test.ts
similarity index 100%
rename from tests/unit/shared-context.test.ts
rename to packages/agent/tests/unit/shared-context.test.ts
diff --git a/tests/unit/tool-context.test.ts b/packages/agent/tests/unit/tool-context.test.ts
similarity index 100%
rename from tests/unit/tool-context.test.ts
rename to packages/agent/tests/unit/tool-context.test.ts
diff --git a/tests/unit/tool-event-broadcaster.test.ts b/packages/agent/tests/unit/tool-event-broadcaster.test.ts
similarity index 100%
rename from tests/unit/tool-event-broadcaster.test.ts
rename to packages/agent/tests/unit/tool-event-broadcaster.test.ts
diff --git a/tests/unit/tool-executor-return.test.ts b/packages/agent/tests/unit/tool-executor-return.test.ts
similarity index 100%
rename from tests/unit/tool-executor-return.test.ts
rename to packages/agent/tests/unit/tool-executor-return.test.ts
diff --git a/tests/unit/tool-type-compat.test.ts b/packages/agent/tests/unit/tool-type-compat.test.ts
similarity index 100%
rename from tests/unit/tool-type-compat.test.ts
rename to packages/agent/tests/unit/tool-type-compat.test.ts
diff --git a/tests/unit/turn-end-race-condition.test.ts b/packages/agent/tests/unit/turn-end-race-condition.test.ts
similarity index 100%
rename from tests/unit/turn-end-race-condition.test.ts
rename to packages/agent/tests/unit/turn-end-race-condition.test.ts
diff --git a/tests/utils/schema-test-helpers.ts b/packages/agent/tests/utils/schema-test-helpers.ts
similarity index 100%
rename from tests/utils/schema-test-helpers.ts
rename to packages/agent/tests/utils/schema-test-helpers.ts
diff --git a/packages/agent/tsconfig.json b/packages/agent/tsconfig.json
new file mode 100644
index 0000000..51bb3ed
--- /dev/null
+++ b/packages/agent/tsconfig.json
@@ -0,0 +1,8 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "esm"
+  },
+  "include": ["src"],
+  "exclude": ["node_modules", "esm"]
+}
diff --git a/vitest.config.ts b/packages/agent/vitest.config.ts
similarity index 94%
rename from vitest.config.ts
rename to packages/agent/vitest.config.ts
index efca4ae..2963346 100644
--- a/vitest.config.ts
+++ b/packages/agent/vitest.config.ts
@@ -2,7 +2,7 @@ import { config } from 'dotenv';
 import { defineConfig } from 'vitest/config';
 
 config({
-  path: new URL('.env', import.meta.url),
+  path: new URL('../../.env', import.meta.url),
 });
 
 export default defineConfig({
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 781287c..4963f56 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -7,13 +7,6 @@ settings:
 importers:
 
   .:
-    dependencies:
-      '@openrouter/sdk':
-        specifier: ^0.12.12
-        version: 0.12.12
-      zod:
-        specifier: ^4.0.0
-        version: 4.3.6
     devDependencies:
       '@biomejs/biome':
         specifier: ^2.4.10
@@ -33,6 +26,9 @@ importers:
       husky:
         specifier: ^9.1.7
         version: 9.1.7
+      turbo:
+        specifier: 2.9.6
+        version: 2.9.6
       typescript:
         specifier: ~5.8.3
         version: 5.8.3
@@ -40,6 +36,15 @@ importers:
         specifier: ^3.2.4
         version: 3.2.4(@types/node@22.19.15)
 
+  packages/agent:
+    dependencies:
+      '@openrouter/sdk':
+        specifier: ^0.12.12
+        version: 0.12.12
+      zod:
+        specifier: ^4.0.0
+        version: 4.3.6
+
 packages:
 
   '@babel/runtime@7.29.2':
@@ -474,6 +479,36 @@ packages:
     cpu: [x64]
     os: [win32]
 
+  '@turbo/darwin-64@2.9.6':
+    resolution: {integrity: sha512-X/56SnVXIQZBLKwniGTwEQTGmtE5brSACnKMBWpY3YafuxVYefrC2acamfjgxP7BG5w3I+6jf0UrLoSzgPcSJg==}
+    cpu: [x64]
+    os: [darwin]
+
+  '@turbo/darwin-arm64@2.9.6':
+    resolution: {integrity: sha512-aalBeSl4agT/QtYGDyf/XLajedWzUC9Vg/pm/YO6QQ93vkQ91Vz5uK1ta5RbVRDozQSz4njxUNqRNmOXDzW+qw==}
+    cpu: [arm64]
+    os: [darwin]
+
+  '@turbo/linux-64@2.9.6':
+    resolution: {integrity: sha512-YKi05jnNHaD7vevgYwahpzGwbsNNTwzU2c7VZdmdFm7+cGDP4oREUWSsainiMfRqjRuolQxBwRn8wf1jmu+YZA==}
+    cpu: [x64]
+    os: [linux]
+
+  '@turbo/linux-arm64@2.9.6':
+    resolution: {integrity: sha512-02o/ZS69cOYEDczXvOB2xmyrtzjQ2hVFtWZK1iqxXUfzMmTjZK4UumrfNnjckSg+gqeBfnPRHa0NstA173Ik3g==}
+    cpu: [arm64]
+    os: [linux]
+
+  '@turbo/windows-64@2.9.6':
+    resolution: {integrity: sha512-wVdQjvnBI15wB6JrA+43CtUtagjIMmX6XYO758oZHAsCNSxqRlJtdyujih0D8OCnwCRWiGWGI63zAxR0hO6s9g==}
+    cpu: [x64]
+    os: [win32]
+
+  '@turbo/windows-arm64@2.9.6':
+    resolution: {integrity: sha512-1XUUyWW0W6FTSqGEhU8RHVqb2wP1SPkr7hIvBlMEwH9jr+sJQK5kqeosLJ/QaUv4ecSAd1ZhIrLoW7qslAzT4A==}
+    cpu: [arm64]
+    os: [win32]
+
   '@types/chai@5.2.3':
     resolution: {integrity: sha512-Mw558oeA9fFbv65/y4mHtXDs9bPnFMZAL/jxdPFUpOHHIXX91mcgEHbS5Lahr+pwZFR8A7GQleRWeI6cGFC2UA==}
 
@@ -952,6 +987,10 @@ packages:
   tr46@0.0.3:
     resolution: {integrity: sha512-N3WMsuqV66lT30CrXNbEjx4GEwlow3v6rr4mCcv6prnfwhS01rkgyFdjPNBYd9br7LpXV1+Emh01fHnq2Gdgrw==}
 
+  turbo@2.9.6:
+    resolution: {integrity: sha512-+v2QJey7ZUeUiuigkU+uFfklvNUyPI2VO2vBpMYJA+a1hKFLFiKtUYlRHdb3P9CrAvMzi0upbjI4WT+zKtqkBg==}
+    hasBin: true
+
   typescript@5.8.3:
     resolution: {integrity: sha512-p1diW6TqL9L07nNxvRMM7hMMw4c5XOo/1ibL4aAIGmSAt9slTE1Xgw5KWuof2uTOvCg9BY7ZRi+GaF+7sfgPeQ==}
     engines: {node: '>=14.17'}
@@ -1447,6 +1486,24 @@ snapshots:
   '@rollup/rollup-win32-x64-msvc@4.60.1':
     optional: true
 
+  '@turbo/darwin-64@2.9.6':
+    optional: true
+
+  '@turbo/darwin-arm64@2.9.6':
+    optional: true
+
+  '@turbo/linux-64@2.9.6':
+    optional: true
+
+  '@turbo/linux-arm64@2.9.6':
+    optional: true
+
+  '@turbo/windows-64@2.9.6':
+    optional: true
+
+  '@turbo/windows-arm64@2.9.6':
+    optional: true
+
   '@types/chai@5.2.3':
     dependencies:
       '@types/deep-eql': 4.0.2
@@ -1895,6 +1952,15 @@ snapshots:
 
   tr46@0.0.3: {}
 
+  turbo@2.9.6:
+    optionalDependencies:
+      '@turbo/darwin-64': 2.9.6
+      '@turbo/darwin-arm64': 2.9.6
+      '@turbo/linux-64': 2.9.6
+      '@turbo/linux-arm64': 2.9.6
+      '@turbo/windows-64': 2.9.6
+      '@turbo/windows-arm64': 2.9.6
+
   typescript@5.8.3: {}
 
   undici-types@6.21.0: {}
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
new file mode 100644
index 0000000..eb019e8
--- /dev/null
+++ b/pnpm-workspace.yaml
@@ -0,0 +1,6 @@
+packages:
+  - "packages/*"
+
+onlyBuiltDependencies:
+  - "@openrouter/sdk"
+  - esbuild
diff --git a/tsconfig.json b/tsconfig.base.json
similarity index 92%
rename from tsconfig.json
rename to tsconfig.base.json
index a01be63..b6d1f9d 100644
--- a/tsconfig.json
+++ b/tsconfig.base.json
@@ -14,7 +14,6 @@
     "declaration": true,
     "declarationMap": true,
     "sourceMap": true,
-    "outDir": "esm",
 
     "strict": true,
     "allowUnusedLabels": false,
@@ -33,7 +32,5 @@
     "esModuleInterop": true,
     "skipLibCheck": true,
     "forceConsistentCasingInFileNames": true
-  },
-  "include": ["src"],
-  "exclude": ["node_modules"]
+  }
 }
diff --git a/turbo.json b/turbo.json
new file mode 100644
index 0000000..3afa862
--- /dev/null
+++ b/turbo.json
@@ -0,0 +1,50 @@
+{
+  "$schema": "https://turbo.build/schema.json",
+  "ui": "stream",
+  "globalDependencies": ["tsconfig.base.json"],
+  "tasks": {
+    "build": {
+      "dependsOn": ["^build"],
+      "inputs": ["$TURBO_DEFAULT$", "src/**", "tsconfig.json"],
+      "outputs": ["esm/**"]
+    },
+    "typecheck": {
+      "dependsOn": ["^build"],
+      "inputs": ["$TURBO_DEFAULT$", "src/**", "tests/**", "tsconfig.json"],
+      "outputs": []
+    },
+    "lint": {
+      "inputs": ["$TURBO_DEFAULT$", "src/**", "tests/**"],
+      "outputs": []
+    },
+    "test": {
+      "dependsOn": ["^build"],
+      "inputs": [
+        "$TURBO_DEFAULT$",
+        "src/**",
+        "tests/unit/**",
+        "vitest.config.ts",
+        "tsconfig.json"
+      ],
+      "outputs": []
+    },
+    "test:watch": {
+      "cache": false,
+      "persistent": true,
+      "env": ["OPENROUTER_API_KEY"]
+    },
+    "test:e2e": {
+      "dependsOn": ["^build"],
+      "inputs": [
+        "$TURBO_DEFAULT$",
+        "src/**",
+        "tests/e2e/**",
+        "vitest.config.ts",
+        "tsconfig.json"
+      ],
+      "outputs": [],
+      "cache": false,
+      "env": ["OPENROUTER_API_KEY"]
+    }
+  }
+}