Google Agent Platform

Claude Fable 5.1

claude-fable-5-1

Claude model for demanding reasoning and long-horizon agentic work

VisionTool CallingCachingReasoningWeb
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Quick facts

Released
September 2026
Model type
Proprietary
Model family
Claude Fable
Input modalities
Supports: Text, Image, PDF
Output modalities
Supports: Text
Available regions
USEUGlobal
Zero data retention
Yes
Available on nexos.ai
Yes

Pricing and specifications of Claude Fable 5.1

Explore Claude Fable 5.1 pricing per million input, output, and cached tokens, along with its context window and maximum output limits.

Input / 1MOutput / 1MCached input / 1MContextMax output
$10.00$50.00$0.251M128K

Available providers

Provider Region Input / 1M Output / 1M Cache / 1M ZDR
Google Agent Platform EU $11.00 $55.00 $0.28
Google Agent Platform US $11.00 $55.00 $0.28
Google Agent Platform Global $10.00 $50.00 $0.25
Bedrock Global $10.00 $50.00 $0.25 –

Specifications

Context window

1M tokens

Max output

128K tokens

Input

Output

Benchmarks of Claude Fable 5.1

How Claude Fable 5.1 scores on independent benchmarks tracked by Epoch AI.

Quality

Epoch Capabilities Index

166.4

ECI rank

#6 of 271

ARC-AGI-2

Abstract reasoning on novel puzzles

90.0%

FrontierMath

Expert-level mathematics

94.9%

OTIS Mock AIME

Competition mathematics

100.0%

WeirdML

Novel machine-learning tasks

92.9%

APEX-Agents

Long-horizon professional services tasks

68.6%

Remote Labor Index

Real freelance projects, end to end

17.9%

SimpleQA Verified

Short-form factual accuracy

70.8%

Benchmark data: Epoch AI, ‘Capabilities & benchmarking’ , licensed under CC BY 4.0 .

Quickstart

Start using Claude Fable 5.1

Model ID

claude-fable-5-1

Base URL

https://api.nexos.ai/v1

Code

 
from openai import OpenAI

# Get your API key from the nexos.ai dashboard
client = OpenAI(
    base_url="https://api.nexos.ai/v1",
    api_key="YOUR_NEXOS_API_KEY",
)

response = client.chat.completions.create(
    model="claude-fable-5-1",
    messages=[{"role": "user", "content": "Hello!"}],
)

print(response.choices[0].message.content)
import OpenAI from 'openai';

// Get your API key from the nexos.ai dashboard
const client = new OpenAI({
  baseURL: 'https://api.nexos.ai/v1',
  apiKey: 'YOUR_NEXOS_API_KEY',
});

const response = await client.chat.completions.create({
  model: 'claude-fable-5-1',
  messages: [{ role: 'user', content: 'Hello!' }],
});

console.log(response.choices[0].message.content);
curl https://api.nexos.ai/v1/chat/completions \
  -H "Authorization: Bearer YOUR_NEXOS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-fable-5-1",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Other Anthropic models

Models from Anthropic with comparable capabilities and pricing.

ModelInputOutputContextCapabilitiesRegion
Claude Opus 5.5$4.40$22.001M
VisionToolsCacheThinkWeb
USEUGlobal
Claude Fable 5$11.00$55.00872K
VisionToolsCacheThinkWeb
USEUGlobal
Claude Haiku 4.5$1.10$5.50136K
VisionToolsCacheThinkWeb
USEUGlobal

Start building with Claude Fable 5.1

Access Claude Fable 5.1 and 200+ other AI models through nexos.ai.

Talk to Solutions Engineer Explore all models ⁠‌

FAQ

Common questions about Claude Fable 5.1, its availability and usage.