gpt-5
GPT-5 is an OpenAI model with major improvements in reasoning, code quality and user experience, optimized for complex tasks that need step-by-step reasoning, instruction following and accuracy. It takes text, image and file input with a 400K context window. OpenRouter lists this model as scheduled for retirement on 2026-12-11.
料金： 入力：100 万トークンあたり 300 クレジット（約 $1.50）、出力：100 万トークンあたり 2400 クレジット（約 $12.00）。
今日はどんなお手伝いができますか？
このデモページにはクライアントの完全な記憶機能はありません。すべての機能をご利用いただくには、クライアントまたは CLI から接続してください。
GPT-5 API on ModelFold
GPT-5 is an OpenAI model with major improvements in reasoning, code quality and user experience, optimized for complex tasks that need step-by-step reasoning, instruction following and accuracy. It takes text, image and file input with a 400K context window. OpenRouter lists this model as scheduled for retirement on 2026-12-11. Try GPT-5 in the ModelFold Playground, then call it from your own code through an OpenAI-compatible chat completions API.
What Is the GPT-5 API
GPT-5 at a glance
GPT-5 is a chat model from OpenAI. It accepts text, images and files (such as PDF) as input and returns text, with a context window of up to 400K tokens.
Use it without hosting anything
On ModelFold you call GPT-5 with a single API key — no model weights to download and no inference servers to run. The same key also works for the other chat, image, video and audio models on ModelFold.
Core Capabilities of GPT-5
Up to 400K tokens of context
Keep long conversations, large documents and sizeable code in a single request, so the model can reason over the full material instead of fragments.
Understands images and files (such as PDF)
Besides text, GPT-5 accepts images and files (such as PDF) as input, so a single request can combine instructions with visual or other media.
Function calling
GPT-5 supports tool (function) calling: describe your functions in the request and the model returns structured calls your code can run — the basis for agents and integrations.
Adjustable reasoning effort
Choose a reasoning effort level (low, medium or high) per request to balance depth of thinking against speed and token usage.
Structured outputs
Ask for JSON that follows a schema (response_format), which makes extraction, classification and system integrations more reliable.
How to Use GPT-5 on ModelFold
- 1
Step 1: Try it in the Playground
Open the Playground at the top of this page, type a prompt and see how GPT-5 responds before writing any code.
- 2
Step 2: Create an API key
Sign in to ModelFold and create an API key in the console. Keep it secret and send it as a Bearer token.
- 3
Step 3: Send a request
Call POST https://modelfold.ai/v1/chat/completions with "model": "gpt-5" and your messages. Existing OpenAI-compatible SDKs work by changing the base URL and key.
- ✓
Step 4: Ship and monitor
Integrate the response into your product and check token usage and spend for every call in the console logs.
What You Can Build with GPT-5
Analysis and complex reasoning
Work through research questions, data interpretation, planning and other problems that need careful step-by-step reasoning.
AI coding assistants
Generate, explain, debug and refactor code, review pull requests and work through multi-file changes in developer tools and IDE plugins.
Autonomous agents
Build agents that plan multi-step tasks, call your tools and APIs, and keep working toward a goal across long sessions.
Long-document workflows
Feed in long reports, contracts, manuals or codebases and ask for summaries, comparisons and answers grounded in the material.
Frequently Asked Questions
What is GPT-5?⌄
GPT-5 is an OpenAI model with major improvements in reasoning, code quality and user experience, optimized for complex tasks that need step-by-step reasoning, instruction following and accuracy. It takes text, image and file input with a 400K context window. OpenRouter lists this model as scheduled for retirement on 2026-12-11.
Which inputs does GPT-5 support?⌄
GPT-5 accepts text, images and files (such as PDF) and returns text. Through ModelFold you can send text and images (OpenAI-style image_url content); in the Playground you can also attach documents, which are converted to text.
How long is the context window of GPT-5?⌄
Up to 400K tokens, shared between your input and the model’s output.
Does GPT-5 support function calling?⌄
Yes. GPT-5 supports tools / function calling through the standard tools parameter of the chat completions API.
How is GPT-5 billed on ModelFold?⌄
Pay as you go by tokens: input and output tokens are charged at the per-million-token prices shown on this page. There is no monthly fee, and failed requests are not charged.
How do I call GPT-5 through the API?⌄
Send a POST request to https://modelfold.ai/v1/chat/completions with "model": "gpt-5", using your ModelFold API key as the Bearer token.
| 入力 | 300 クレジット 1M tokens≈ $1.50 |
| 出力 | 2400 クレジット 1M tokens≈ $12.00 |
トークン単位で課金し、入力と出力は別料金です。思考トークンは出力に含まれます。Playground でも同じ計算を使います。
API ドキュメントを見る →AI Agents · Claude Code / Cursor / Trae →curl https://modelfold.ai/v1/chat/completions \
-H "Authorization: Bearer $MODELFOLD_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"gpt-5","messages":[{"role":"user","content":"Hello"}]}'