Using Claude Fable 5 on Anthropic

Quick Start

1. 1
   Create an account at Anthropic and generate an API key.
2. 2
   Use the Anthropic SDK or REST API to call claude-fable-5 — see the documentation for request format.
3. 3
   You'll be billed $10.00/1M input, $50.00/1M output tokens. See full pricing.

Code Examples

import anthropic

client = anthropic.Anthropic()  # reads ANTHROPIC_API_KEY from env
message = client.messages.create(
    model="claude-fable-5",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello"}]
)
print(message.content[0].text)

About Anthropic

Creator of Claude AI models, accessed via the Anthropic API and the Anthropic Console (console.anthropic.com). The Console hosts the Workbench prompt playground, API keys, usage analytics, and team billing.

Anthropic is a safety-focused AI research company and creator of the Claude model family, offering API access through the Anthropic Console for text generation, analysis, and coding tasks.

Pricing on Anthropic

Capabilities

About Claude Fable 5

Anthropic's most capable widely released model, built for demanding reasoning and long-horizon agentic work. Claude Fable 5 is the generally available Mythos-class Claude model, supports vision, tool use, structured outputs, prompt caching, Batch API processing, adaptive thinking that is always on, a 1M-token context window, and up to 128k output tokens. It is available through the Claude API, AWS Bedrock, Vertex AI, and Microsoft Foundry as of June 9, 2026, with first-party pricing at $10 per 1M input tokens and $50 per 1M output tokens.