Anthropic · MultimodalReleased 2026-08-31

claude-fable-5.1

anthropic/claude-fable-5.1 id

Claude Fable 5.1 improves on Fable 5 across long-running agentic coding, knowledge work, and research, following instructions precisely over sessions that run unattended for hours.

ReasoningTool useChatStructured output
Type
Use claude-fable-5.1
# Drop-in OpenAI-compatible client
$ import { generateText } from 'ai'
$
$ const { text } = await generateText({
$ model: 'anthropic/claude-fable-5.1',
$ baseURL: 'https://synapse.garden/api/v1',
$ apiKey: process.env.MG_KEY,
$ prompt: 'Why is the sky blue?',
$ })
1M
CONTEXT WINDOW
128K
MAX OUTPUT
$11.00/M
INPUT · PER M
$55.00/M
OUTPUT · PER M
PRICING

List prices, every modality.

RatePer million tokens · USD
Input$11.00/M
Output$55.00/M
Cache read$0.275/M
Cache write$13.75/M
Honest list pricesHow we calculate prices
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FAQ · CLAUDE-FABLE-5.1

Frequently asked

01 / 04

How do I call claude-fable-5.1 from my code?

Use the OpenAI or Anthropic SDK and point baseURL at https://synapse.garden/api/v1. Set model: ‘anthropic/claude-fable-5.1’ and supply your Synapse Garden API key. No code changes beyond the base URL.

02 / 04

How much does claude-fable-5.1 cost?

Input: $11.00/M per million tokens. Output: $55.00/M per million tokens. The free tier includes a million tokens every month at no cost.

03 / 04

What's the context window for claude-fable-5.1?

claude-fable-5.1 supports a context window of 1M tokens, with a maximum output of 128K tokens.

04 / 04

Do I need a separate Anthropic or OpenAI account?

No. Synapse Garden is the single API surface — one key gives you OpenAI, Anthropic, Google, Meta, Mistral, DeepSeek, xAI, Cohere, and more. Billing, rate limits, and audit logs are unified.

READY

Try claude-fable-5.1 in three minutes.

Sign up, create a key, drop our base URL into your existing client. The free tier includes a million tokens every month — no credit card.