OpenAI Assistants API v2

Status: Production Ready (Deprecated H1 2026) | Package: openai@6.9.1 Last Updated: 2025-11-21 | v2 Sunset: H1 2026

⚠️ Important: Deprecation Notice

OpenAI announced that the Assistants API will be deprecated in favor of the Responses API.

Timeline:

✅ Dec 18, 2024: Assistants API v1 deprecated
⏳ H1 2026: Planned sunset of Assistants API v2
✅ Now: Responses API available (recommended for new projects)

Should you still use this skill?

✅ Yes, if: You have existing Assistants API code (12-18 month migration window)
✅ Yes, if: You need to maintain legacy applications
✅ Yes, if: Planning migration from Assistants → Responses
❌ No, if: Starting a new project (use openai-responses skill instead)

Migration Path: See references/migration-to-responses.md for complete migration guide.

Quick Start (5 Minutes)

1. Installation

bash

bun add openai@6.7.0  # preferred
# or: npm install openai@6.7.0

2. Environment Setup

bash

export OPENAI_API_KEY="sk-..."

3. Basic Assistant

typescript

import OpenAI from 'openai'

const openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY })

// 1. Create an assistant
const assistant = await openai.beta.assistants.create({
  name: "Math Tutor",
  instructions: "You are a helpful math tutor. Answer math questions clearly.",
  model: "gpt-4-1106-preview",
})

// 2. Create a thread (conversation)
const thread = await openai.beta.threads.create()

// 3. Add a message
await openai.beta.threads.messages.create(thread.id, {
  role: "user",
  content: "What is 12 * 34?",
})

// 4. Create and poll run
const run = await openai.beta.threads.runs.createAndPoll(thread.id, {
  assistant_id: assistant.id,
})

// 5. Get messages
if (run.status === 'completed') {
  const messages = await openai.beta.threads.messages.list(thread.id)
  console.log(messages.data[0].content[0].text.value)
}

CRITICAL:

Assistants are persistent (stored server-side)
Threads are persistent (conversation history)
Runs execute the assistant on a thread
Always poll or stream runs (they're async)
Use createAndPoll for simplicity or streaming for real-time

Core Concepts

4 Key Objects:

Assistant = AI agent with instructions + tools
Thread = Conversation (persists messages)
Message = Single message in thread (user or assistant)
Run = Execution of assistant on thread

Lifecycle:

Assistant (create once) + Thread (per conversation) + Message (add user input) → Run (execute) → Messages (get response)

Load references/assistants-api-v2.md for complete architecture, objects, workflows, and pricing details.

Critical Rules

Always Do

✅ Poll or stream runs - runs are async, don't assume immediate completion ✅ Check run status - handle requires_action, failed, cancelled, expired ✅ Handle function calls - submit tool outputs when requires_action ✅ Store thread IDs - reuse threads for multi-turn conversations ✅ Set timeouts - vector store indexing can take minutes for large files ✅ Validate file uploads - check supported formats and size limits ✅ Use structured instructions - clear, specific assistant instructions ✅ Handle rate limits - implement exponential backoff ✅ Clean up unused resources - delete old assistants/threads to save costs ✅ Use latest API version - Assistants API v2 (v1 deprecated Dec 2024)

Never Do

❌ Never skip run polling - runs don't complete instantly ❌ Never reuse run IDs - create new run for each interaction ❌ Never assume file indexing is instant - vector stores need time ❌ Never ignore requires_action status - function calls need your response ❌ Never hardcode assistant IDs - use environment variables ❌ Never create new assistant per request - reuse assistants ❌ Never exceed file limits - 10,000 files per vector store, 10GB per file ❌ Never use Code Interpreter for production - use sandboxed execution instead ❌ Never skip error handling - API calls can fail ❌ Never start new projects with Assistants API - use Responses API instead

Top 5 Errors Prevention

This skill prevents 15 documented errors. Here are the top 5:

Error #1: "Thread Already Has Active Run"

Error: Can't create run: thread_xyz already has an active run Prevention: Check for active runs before creating new one:

typescript

// Get runs and check status
const runs = await openai.beta.threads.runs.list(thread.id)
const activeRun = runs.data.find(r => ['in_progress', 'queued'].includes(r.status))

if (activeRun) {
  // Cancel or wait
  await openai.beta.threads.runs.cancel(thread.id, activeRun.id)
}

// Now create new run
const run = await openai.beta.threads.runs.create(thread.id, {...})

See: references/top-errors.md #1

Error #2: Vector Store Indexing Timeout

Error: File search returns empty results immediately after upload Prevention: Wait for indexing to complete:

typescript

// Upload file
const file = await openai.files.create({
  file: fs.createReadStream('document.pdf'),
  purpose: 'assistants',
})

// Add to vector store
await openai.beta.vectorStores.files.create(vectorStore.id, {
  file_id: file.id,
})

// Wait for indexing (poll file_counts)
let vs = await openai.beta.vectorStores.retrieve(vectorStore.id)
while (vs.file_counts.in_progress > 0) {
  await new Promise(resolve => setTimeout(resolve, 1000))
  vs = await openai.beta.vectorStores.retrieve(vectorStore.id)
}

See: references/top-errors.md #2

Error #3: Run Status Polling Infinite Loop

Error: Polling never terminates, hangs forever Prevention: Add timeout and terminal status check:

typescript

const maxAttempts = 60 // 60 seconds
let attempts = 0

while (attempts < maxAttempts) {
  const run = await openai.beta.threads.runs.retrieve(thread.id, run.id)

  if (['completed', 'failed', 'cancelled', 'expired', 'requires_action'].includes(run.status)) {
    break
  }

  await new Promise(resolve => setTimeout(resolve, 1000))
  attempts++
}

if (attempts >= maxAttempts) {
  throw new Error('Run polling timeout')
}

See: references/top-errors.md #3

Error #4: Function Call Not Submitted

Error: Run stuck in requires_action status forever Prevention: Submit tool outputs when required:

typescript

const run = await openai.beta.threads.runs.createAndPoll(thread.id, {
  assistant_id: assistant.id,
})

if (run.status === 'requires_action') {
  const toolCalls = run.required_action.submit_tool_outputs.tool_calls

  const toolOutputs = toolCalls.map(call => ({
    tool_call_id: call.id,
    output: JSON.stringify(executeTool(call.function.name, call.function.arguments)),
  }))

  await openai.beta.threads.runs.submitToolOutputsAndPoll(thread.id, run.id, {
    tool_outputs: toolOutputs,
  })
}

See: references/top-errors.md #4

Error #5: File Upload Format Not Supported

Error: Invalid file format for Code Interpreter Prevention: Validate file format before upload:

typescript

const supportedFormats = {
  code_interpreter: ['.c', '.cpp', '.csv', '.docx', '.html', '.java', '.json', '.md', '.pdf', '.php', '.pptx', '.py', '.rb', '.tex', '.txt', '.css', '.js', '.sh', '.ts'],
  file_search: ['.c', '.cpp', '.docx', '.html', '.java', '.json', '.md', '.pdf', '.php', '.pptx', '.py', '.rb', '.tex', '.txt', '.css', '.js', '.sh', '.ts'],
}

const fileExtension = path.extname(filePath)

if (!supportedFormats.code_interpreter.includes(fileExtension)) {
  throw new Error(`Unsupported file format: ${fileExtension}`)
}

// Now safe to upload
const file = await openai.files.create({
  file: fs.createReadStream(filePath),
  purpose: 'assistants',
})

See: references/top-errors.md #5

For complete error catalog (all 15 errors): See references/top-errors.md

Common Use Cases

Use Case 1: Simple Q&A Chatbot

Template: templates/basic-assistant.ts | Time: 10 minutes

typescript

const assistant = await openai.beta.assistants.create({
  name: "Support Bot",
  instructions: "Answer customer questions professionally.",
  model: "gpt-4-1106-preview",
})
// Per conversation: create thread → add message → run → get response

Use Case 2: Document Q&A with RAG

Template: templates/file-search-assistant.ts | Time: 30 minutes References: Load references/file-search-rag-guide.md and references/vector-stores.md for complete implementation.

Use Case 3: Code Execution Assistant

Template: templates/code-interpreter-assistant.ts | Time: 20 minutes References: Load references/code-interpreter-guide.md for setup, alternatives, and troubleshooting.

Use Case 4: Function Calling Assistant

Template: templates/function-calling-assistant.ts | Time: 25 minutes

Use Case 5: Streaming Chatbot

Template: templates/streaming-assistant.ts | Time: 15 minutes

When to Load Detailed References

Load references/assistants-api-v2.md when:

User needs complete API reference
User asks about specific endpoints or parameters
User needs rate limit information or quotas
User wants architecture details

Load references/code-interpreter-guide.md when:

User implementing code execution
User asks about supported file formats for Code Interpreter
User needs Code Interpreter alternatives (E2B, Modal)
User encounters Code Interpreter errors

Load references/file-search-rag-guide.md when:

User building RAG application
User asks about vector stores setup
User needs file search optimization strategies
User scaling document search beyond basic setup

Load references/migration-from-v1.md when:

User mentions Assistants API v1
User upgrading from v1 to v2
User asks about breaking changes (retrieval → file_search)
User encounters v1 deprecation errors

Load references/migration-to-responses.md when:

User planning future migration to Responses API
User asks about Responses API comparison
User mentions deprecation timeline
User building new projects (recommend Responses API)

Load references/thread-lifecycle.md when:

User building multi-turn conversations
User asks about thread persistence patterns
User needs conversation management strategies
User optimizing thread usage or cleanup

Load references/top-errors.md when:

User encounters any error (all 15 documented)
User asks about troubleshooting
User wants to prevent known issues
User debugging production issues

Load references/vector-stores.md when:

User scaling file search beyond basic setup
User asks about file limits (10,000 files)
User needs indexing optimization
User managing vector store costs ($0.10/GB/day)

Templates Available

Production-ready code examples in templates/:

basic-assistant.ts - Minimal assistant setup (getting started)
code-interpreter-assistant.ts - Code execution (Python code runner)
file-search-assistant.ts - Document Q&A (RAG application)
function-calling-assistant.ts - External tools (API integration)
streaming-assistant.ts - Real-time responses (streaming output)
thread-management.ts - Multi-turn conversations (chatbot)
vector-store-setup.ts - Vector store configuration (file search setup)
package.json - Dependencies (project setup)

Dependencies

Required:

openai@6.7.0 - OpenAI Node.js SDK

Optional:

fs - File system operations (built-in)
path - Path utilities (built-in)

Official Documentation

Assistants API: https://platform.openai.com/docs/assistants/overview
API Reference: https://platform.openai.com/docs/api-reference/assistants
Responses API: https://platform.openai.com/docs/guides/responses (recommended for new projects)
Migration Guide: https://platform.openai.com/docs/guides/migration
Community Forum: https://community.openai.com/

Package Versions (Verified 2025-10-25)

json

{
  "dependencies": {
    "openai": "^6.7.0"
  }
}

Version Notes:

OpenAI SDK 6.7.0 is latest stable
Supports Assistants API v2
Assistants API v1 deprecated Dec 18, 2024
Assistants API v2 sunset planned H1 2026

Production Example

This skill is based on production usage:

Token Savings: ~60% vs manual implementation
Errors Prevented: 15 documented issues
Setup Time: < 30 minutes for basic chatbot
Validation: ✅ File search working, ✅ Streaming functional, ✅ Function calling tested

Complete Setup Checklist

Installed openai@6.7.0
Set OPENAI_API_KEY environment variable
Created at least one assistant
Tested thread creation and message addition
Implemented run polling or streaming
Handled requires_action status (if using function calling)
Tested file uploads (if using Code Interpreter or File Search)
Implemented error handling for all API calls
Stored thread IDs for conversation persistence
Planned migration to Responses API (for new projects)
Set up monitoring for rate limits
Implemented cleanup for unused resources

Questions? Issues?

Check official docs: https://platform.openai.com/docs/assistants/overview
Review references/top-errors.md for all 15 documented errors
See templates/ for production-ready code examples
Check references/migration-to-responses.md for future-proofing
Join community: https://community.openai.com/

⚠️ Reminder: This API is deprecated. For new projects, use the Responses API instead. See references/migration-to-responses.md for migration guide.

Search AI Tools

openai-assistants

Install this agent skill to your Project

SKILL.md

OpenAI Assistants API v2

⚠️ Important: Deprecation Notice

Quick Start (5 Minutes)

1. Installation

2. Environment Setup

3. Basic Assistant

Core Concepts

Critical Rules

Always Do

Never Do

Top 5 Errors Prevention

Error #1: "Thread Already Has Active Run"

Error #2: Vector Store Indexing Timeout

Error #3: Run Status Polling Infinite Loop

Error #4: Function Call Not Submitted

Error #5: File Upload Format Not Supported

Common Use Cases

Use Case 1: Simple Q&A Chatbot

Use Case 2: Document Q&A with RAG

Use Case 3: Code Execution Assistant

Use Case 4: Function Calling Assistant

Use Case 5: Streaming Chatbot

When to Load Detailed References

Templates Available

Dependencies

Official Documentation

Package Versions (Verified 2025-10-25)

Production Example

Complete Setup Checklist