claude-opus-4-8Anthropic's most capable model to date — built to autonomously carry long, complex work end to end. Ideal for developers shipping large projects, building agents, and high-stakes scenarios that demand top-tier quality and autonomy.
Anthropic's strongest model for long, complex work
Sustains complex multi-step tasks end to end
Ideal for large projects and autonomous agent workflows
For scenarios demanding top-tier quality and self-direction
View complete API reference with all parameters and examples.
Enable real-time streaming responses with Server-Sent Events.
{
"model": "claude-opus-4-8",
"stream": true,
"max_tokens": 1024,
"messages": [...]
}Enable Claude to use tools and call functions.
{
"model": "claude-opus-4-8",
"max_tokens": 1024,
"tools": [{
"name": "get_weather",
"description": "Get current weather for a location",
"input_schema": {
"type": "object",
"properties": {
"location": {"type": "string", "description": "City name"}
},
"required": ["location"]
}
}],
"tool_choice": {"type": "auto"},
"messages": [{"role": "user", "content": "What's the weather in Tokyo?"}]
}Analyze PDF documents by sending them as base64 encoded content.
{
"model": "claude-opus-4-8",
"max_tokens": 1024,
"messages": [{
"role": "user",
"content": [{
"type": "document",
"source": {
"type": "base64",
"media_type": "application/pdf",
"data": "<base64_encoded_pdf>"
}
}, {
"type": "text",
"text": "Summarize this document."
}]
}]
}Get structured JSON responses that match your schema.
{
"model": "claude-opus-4-8",
"max_tokens": 1024,
"output_format": {
"type": "json_schema",
"schema": {
"type": "object",
"properties": {
"name": {"type": "string"},
"age": {"type": "integer"}
},
"required": ["name", "age"]
}
},
"messages": [{"role": "user", "content": "Extract info: John is 30 years old"}]
}Enable Claude to search the web for up-to-date information.
{
"model": "claude-opus-4-8",
"max_tokens": 1024,
"tools": [{
"type": "web_search_20250305",
"name": "web_search",
"max_uses": 5
}],
"messages": [{"role": "user", "content": "What's the latest news about AI?"}]
}| Parameter | Type | Required | Description |
|---|---|---|---|
| model | string | Yes | Model identifier (e.g., claude-opus-4-8) |
| messages | array | Yes | Array of message objects with role and content |
| max_tokens | integer | Yes | Maximum tokens in the response (1 - 128000) |
| system | string | No | System prompt to set context |
| stream | boolean | No | Enable streaming responses (SSE) |
| temperature | number | No | Sampling temperature (0.0 - 1.0) |
| top_p | number | No | Nucleus sampling threshold (0.0 - 1.0) |
| top_k | integer | No | Top-k sampling (0 - infinity) |
| stop_sequences | array | No | Sequences that stop generation |
| tools | array | No | Function calling tools definition |
| tool_choice | object | No | Tool selection strategy (auto/any/tool) |
| thinking | object | No | Enable extended thinking mode |
| output_format | object | No | Structured output with JSON schema |
View complete API reference with streaming, thinking, and more.
Billing: Cost = (input_tokens * input_price + output_tokens * output_price) / 1,000,000
Claude Opus 4.8 is a Large Language Model API provided by Anthropic. Anthropic's most capable model to date — built to autonomously carry long, complex work end to end. Ideal for developers shipping large projects, building agents, and high-stakes scenarios that demand top-tier quality and autonomy. Through API Models platform, you can access this model via a unified API at prices significantly lower than official rates. Current pricing: Input: $3, Output: $13 per 1M tokens.
Build intelligent conversational systems to automatically answer user queries and improve service efficiency.
Automatically write articles, emails, ad copy, and other text content to boost productivity.
Assist with code writing, debugging, and code review to accelerate software development.
Understand and analyze unstructured data, extract key insights, and generate summary reports.
Claude Opus 4.8 is available through API Models at: Input: $3, Output: $13 per 1M tokens. This is up to 95% cheaper than official pricing.
Sign up at API Models, get your API key, and call our unified API endpoint. We provide detailed API documentation with code examples in cURL, Python, and Node.js.
API Models offers the same Claude Opus 4.8 model at 60-95% lower cost through our aggregation platform. We provide a unified API interface so you do not need separate accounts for each provider - one API key to access all models.
Opus 4.8 is Anthropic's most capable model — a 1M-token context window plus strong long-horizon agentic reasoning make it the pick for complex, multi-step coding, analysis, and long tasks where weaker models lose the thread. On API Models it's the default for agentic work.
Opus 4.8 for the hardest reasoning/agentic tasks (highest quality, highest cost); Sonnet 4.6 for a strong quality/price balance on everyday coding and chat; Haiku 4.5 for fast, cheap, high-volume calls. All share one API key, so you can route by task.
Yes — it returns native tool_use blocks for function calling and agent loops, and works in Claude Code: point ANTHROPIC_BASE_URL at our API and set the model to claude-opus-4-8. See /docs/claude-code.
On API Models, Claude Opus 4.8 runs alongside 60+ models on one API key and one balance, so choosing is about fit, not lock-in. It supports Most Capable, Long-Horizon Autonomy, Agentic Workflows, Production Quality, and you can weigh it on price and capability against other Large Language Model models, then switch by changing a single model-name string — no new account or integration. Browse every Large Language Model option with live pricing at apimodels.app/models.
Claude Opus 4.8 supports: Most Capable, Long-Horizon Autonomy, Agentic Workflows, Production Quality. See the API Models docs for full parameters and call examples.
Yes. API Models exposes Claude Opus 4.8 through a single unified API and one key — no separate provider accounts, and no need to handle each provider's regional network access yourself.
We support Stripe (Visa, Mastercard, and other international cards) and Alipay. Credits are available instantly after payment.