AnthropicCertifiedReleased 07/24/2026

Claude Opus 5

Claude Opus 5 is the latest model in Anthropic's Opus family and a step-change improvement over Opus 4.8. It delivers major gains over Opus 4.8 in agentic coding, professional knowledge work, and long-horizon reasoning, and it is stronger per token across effort levels.

View API reference ↓
Input / output priceFrom$5.00 / $25.00per 1M
24h uptime—
import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.inferencebureau.com/v1",
  apiKey: process.env.IB_API_KEY,
});

const res = await client.chat.completions.create({
  model: "anthropic/claude-opus-5-fast",
  messages: [{ role: "user", content: "Why is the sky blue?" }],
});

console.log(res.choices[0].message.content);

Providers

Dispatch routes requests across these providers and fails over between them without changing the model. Restrict or order providers with team Directives. Prices are gateway list prices before the platform fee.

ProviderContextMax outputLatencyThroughputInputOutputCacheCapabilitiesZDRNo trainingRegionsStatus
Anthropic1M128K——$5.00$25.00Read $0.50Write $6.258 featuresYesYesUSCertified

Uptime

24 hours

Request success rate per provider.

Anthropic—

Getting started

Create a key on the API Keys page and set it as IB_API_KEY. See the quickstart.

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.inferencebureau.com/v1",
  apiKey: process.env.IB_API_KEY,
});

const res = await client.chat.completions.create({
  model: "anthropic/claude-opus-5-fast",
  messages: [{ role: "user", content: "Why is the sky blue?" }],
});

console.log(res.choices[0].message.content);

Top-level parameters

Standard Chat Completions parameters work as documented. These have model-specific behavior.

ParameterTypeRequiredDescription
modelstringYesModel ID in the form creator/model, e.g. anthropic/claude-opus-5-fast. Must be allowed by your team's Directives.
max_tokensnumberNoHard cap on generated tokens, and the basis for the balance reserved per request. Claude Opus 5 supports up to 128,000 output tokens.
reasoning{ effort: 'low' | 'medium' | 'high' }NoReasoning effort, mapped to the provider's native configuration. Reasoning tokens count toward output usage.
toolsTool[]NoFunction definitions the model can call. Tool calls are returned in choices[].message.tool_calls.
Supportedmax_tokensstoptoolstool_choicereasoninginclude_reasoningresponse_formatstructured_outputs

Input limits

InputSourcesLimits
Text—Prompt and response share the 1M-token context window
ImageURL, base64Sent as image_url content parts; counts as input tokens
PDFURL, base64Sent as file content parts; counts as input tokens

More models by Anthropic

ModelContextInputOutputCacheRelease
anthropic/claude-haiku-5.51M$0.100$0.50Read $0.010Write $0.1310/07/2026
anthropic/claude-haiku-5.5-batch1M$0.050$0.25Read $0.0050Write $0.06310/07/2026
anthropic/claude-sonnet-5.51M$2.00$10.00Read $0.100Write $2.5009/28/2026
anthropic/claude-sonnet-5.5-batch1M$1.00$5.00Read $0.050Write $1.2509/28/2026
anthropic/claude-opus-5.51M$4.00$20.00Read $0.20Write $5.0009/22/2026
anthropic/claude-opus-5.5-batch1M$2.00$10.00Read $0.100Write $2.5009/22/2026
anthropic/claude-opus-5.5-fast1M$8.00$40.00Read $0.40Write $10.0009/22/2026
anthropic/claude-fable-5.11M$10.00$50.00Read $0.25Write $12.5008/31/2026
anthropic/claude-fable-5.1-batch1M$5.00$25.00Read $0.13Write $6.2508/31/2026
anthropic/claude-opus-51M$5.00$25.00Read $0.50Write $6.2507/24/2026