How do I use Claude Opus 4.8 through YepAPI?

Sign up for a free API key, then send requests to the /v1/ai/chat endpoint.

AnthropicText Generation/v1/ai/chat

Claude Opus 4.8

Access Claude Opus 4.8 through one API key. Anthropic's newest and most intelligent model.

Anthropic's newest flagship. The most capable Claude yet for complex reasoning, agentic tool use, nuanced writing, and advanced coding — with a 1M token context window.

Full Docs Get API Key — Free $5 Credit

No credit card required. Takes 30 seconds.

2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see Claude Opus 4.8 respond in real time.

POST/v1/ai/chatanthropic/claude-opus-4.8

Message *

Max Tokens

Maximum tokens in the response.

Stream

Real-time tokens

Hit "Send Request" to see the response

Context Window

1M tokens

Max Output

32K tokens

Input Price

$7.00 / 1M tokens

Output Price

$35.00 / 1M tokens

Strengths

✓

Newest-generation Claude flagship

Claude Opus 4.8 is Anthropic's most capable Claude, the top tier above Sonnet and Haiku for the hardest work.

✓

1M token context

Reads up to 1,000,000 tokens per request, enough to hold entire codebases, large document sets, or long agent histories.

✓

State-of-the-art reasoning & agents

Tuned for complex reasoning and agentic tool use, making it a strong engine for multi-step agents and deep analysis.

✓

Best-in-class coding & analysis

Excels at advanced coding and nuanced analysis, returning up to 32,000 output tokens per response for substantial work.

Quick start

Copy this snippet and start making calls with Claude Opus 4.8.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "anthropic/claude-opus-4.8",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Why use Claude Opus 4.8 through YepAPI?

✓One API key for all models — no separate accounts

✓OpenAI SDK compatible — just change the base URL

✓No monthly minimums — pay per token

✓Switch models with one line of code

✓Full provider passthrough — citations, search results, and all extras included

✓Streaming and non-streaming support on every model

✓Works with Cursor, Claude, LangChain, and any LLM tool

✓Unified billing across all providers

Claude Opus 4.8 API — pricing, context window & access

Claude Opus 4.8 is Anthropic's newest flagship and the most capable Claude yet for complex reasoning, agentic tool use, nuanced writing, and advanced coding. It carries a 1,000,000-token context window and up to 32,000 output tokens per response.

With YepAPI you reach Claude Opus 4.8 through one OpenAI-compatible key — the same key that also covers Claude Sonnet and Haiku, GPT-5.5, Gemini, and the SEO, SERP and scraping APIs.

What is Claude Opus 4.8?

Claude Opus 4.8 is Anthropic's newest flagship and the top tier of the Claude family, above Sonnet and Haiku. It's the most capable Claude yet, tuned for complex reasoning, agentic tool use, nuanced writing, and advanced coding — the model you reach for when a task demands maximum intelligence rather than speed or low cost. Its 1,000,000-token context window lets it hold entire codebases, large document collections, or long agent transcripts in one request, making it as much an engine for long-running agents as a single-shot reasoner.

Build with Claude Opus 4.8 via YepAPI

YepAPI exposes Claude Opus 4.8 through the OpenAI-compatible /v1/ai/chat endpoint, so you call Anthropic's flagship with the chat-completions format and the model string claude-opus-4.8 — no Anthropic SDK required. Dropping to Claude Sonnet or Haiku for cheaper work, or switching to GPT-5.5 or Gemini, is a one-string change. Your single key also covers search and scraping endpoints, so flagship agents and data pipelines run on the same account.

Claude Opus 4.8 API pricing — $7.00 / 1M input, $35.00 / 1M output

Claude Opus 4.8 costs $7.00 per 1M input tokens and $35.00 per 1M output tokens through YepAPI. As Anthropic's flagship, its rates reflect top-tier capability, so it's best reserved for tasks that genuinely need it — deep reasoning, agentic coding, and nuanced analysis — with routine work routed to Sonnet or Haiku. The 1M-token window means large-context jobs can run up input volume, so size prompts with intent. You pay only for tokens used.

Claude Opus 4.8 for agents & advanced coding

Opus 4.8 is built for the hardest agentic and coding work. Its state-of-the-art reasoning and tool use make it a strong engine for agents that plan, call tools, and iterate over many steps, while the 1M-token context keeps a long working memory of files and history in view. Combined with best-in-class coding and 32K output tokens, it suits autonomous coding, large refactors, and nuanced analysis where flagship intelligence justifies the cost.

Try Claude Opus 4.8 free

Every new YepAPI account includes $5 in free credit, no card required. That's enough to test Opus 4.8's reasoning, coding, and agentic behavior on your own prompts before committing to flagship spend. Create an account, copy your key, and start calling Claude Opus 4.8 right away.

Start generating in 30 seconds

$5 free credit on signup. No credit card required. Pay per call.

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What developers say

“Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.”
Marcus T.
SEO Platform Founder

“One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.”
Priya S.
Full-Stack Developer

“The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.”
Jake R.
Indie Hacker

Frequently asked questions

Anthropic's newest flagship. The most capable Claude yet for complex reasoning, agentic tool use, nuanced writing, and advanced coding — with a 1M token context window.

Input tokens cost $7.00 per 1M tokens and output tokens cost $35.00 per 1M tokens through YepAPI. No monthly minimums — you only pay for what you use.

Claude Opus 4.8 supports a 1M token context window with up to 32K output tokens per request.