Anthropic · Frontier
Claude Fable 5
Anthropic Claude Fable 5 for long-running coding, research, and knowledge-work tasks. Anthropic retains prompts and outputs for 30 days under its Covered Models policy; Zero Data Retention is not available.
- Reasoning
- Tools
- Vision
- Structured output
- PDF input
- Input
- Text, Images
- Output
- Text
- Reasoning effort
- low · medium · high · xhigh · max
- Discovery tier
- Frontier
Pricing
USD per 1M tokens- Input
- $10.00
- Output
- $50.00
- Cache read
- $1.00
- Cache write
- $12.50
- $20.00 for a 1-hour cache
Reference prices as published by the model provider. API example
Specifications
- Context window
- 1M
- Max output
- 128K
- Average output (7 days)
- 1.2K tokens
- Longer than 78% of 473 models
Side by side
Compare models
Put Claude Fable 5 next to up to three other models. The comparison stays in the link, so you can share it.
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
Intelligence Index
49.6
Tested at max reasoning effort
Better than 96% of 326 scored models
Indexes
Coding Index
76.5Composite of the coding evaluations
Better than 92% of 168 scored models
Agentic work
AutomationBench-AA
54.1%Workflow automation, penalized for guardrail violations
Better than 70% of 173 scored models
AutomationBench-AA tasks completed
24.7%Workflows finished end to end without a guardrail violation
Better than 71% of 173 scored models
AA-Briefcasev1.1
1,537 EloAgentic knowledge work, rated head to head
Better than 89% of 166 scored models
GDPval-AAv2.1
1,610 EloEconomically valuable occupational tasks, rated head to head
Better than 86% of 187 scored models
Document reasoning
GDP.pdf
24.0%Professional reasoning over PDF documents, all-pass rate
Better than 85% of 171 scored models
AA-LCRv1.1
82.3%Reasoning across long documents
Better than 87% of 309 scored models
MLCR-AA
20.6%Long-context reasoning over medical records
Better than 83% of 121 scored models
Reasoning and knowledge
Humanity’s Last Exam
55.5%Expert-level questions across academic fields
Better than 98% of 323 scored models
GPQA Diamond
92.6%Graduate-level science questions
Better than 89% of 291 scored models
IFBench
63.5%Following precise output instructions
Better than 63% of 215 scored models
Coding
Terminal-Benchv4.0
42.4%Practical software engineering in a terminal
Better than 89% of 171 scored models
SciCode
61.0%Scientific computing in Python
Better than 98% of 174 scored models
Legacy evaluations
Terminal-Bench Hard
62.9%Earlier terminal task suite
Better than 98% of 212 scored models
τ²-Bench Telecom
98.5%Tool use in a customer-support simulation
Better than 97% of 214 scored models
AA-LCR (unversioned)
82.3%Long-context reasoning, earlier grading
Better than 87% of 309 scored models
Scores from Artificial Analysis, updated Oct 26, 2026. Claude Fable 5 was tested at max reasoning effort; compare scores measured at the same effort.Artificial Analysis
- #5Combined23.5%
Ranks among Noumen catalog models on Combined leaderboards. Only top-20 placements are listed.
- #4Roleplay57.2%
- #5Creative writing50.2%
- #2Coding44.7%
- #4Math34.6%
Ranks among Noumen catalog models on Use cases leaderboards. Only top-20 placements are listed.
- #4Overall1503.3
- #2Coding1550.6
- #4Math1520.7
- #3Longer Query1521.9
- #3Creative Writing1500.5
- #4Instruction Following1507.5
- #4Hard Prompts1528.8
- #4Chinese1554.5
- #5English1511.3
- #4Exclude Ties1522.6
- #1Expert1549.8
- #4French1524.4
- #9German1500.3
- #4Hard Prompts English1530.8
- #5Industry Business And Management And Financial Operations1500.3
- #3Industry Entertainment And Sports And Media1492.4
- #5Industry Legal And Government1510.2
- #3Industry Life And Physical And Social Science1525.4
- #7Industry Mathematical1519.3
- #12Industry Medicine And Healthcare1505.2
- #3Industry Software And It Services1538.3
- #3Industry Writing And Literature And Language1507.5
- #3Japanese1520.7
- #3Korean1496.4
- #3Multi Turn1516.9
- #5Non English1492.5
- #3Polish1509.8
- #4Russian1515.3
- #1Spanish1501.9
- #1Vision Style Control Overall1308.7
- #5Vision Style Control · Chinese1354.6
- #1Vision Style Control · Creative Writing Vision1318.6
- #1Vision Style Control · Diagram1352.6
- #1Vision Style Control · English1303.2
- #2Vision Style Control · Homework1351.9
- #1Vision Style Control · Humor1323.7
- #1Vision Style Control · Ocr1326.4
- #9WebDev · Image To Webdev1622.8
- #11WebDev · Webdev-html1649.6
- #8Search Overall1229.1
- #4Document Overall1496.1
- #1Document Style Control Overall1498.9
Ranks among Noumen catalog models on LMArena leaderboards. Only top-20 placements are listed.LMArena
- #2FrontierCode Main53.5%
- #2FrontierCode Extended64.9%
Ranks among Noumen catalog models on FrontierCode leaderboards. Only top-20 placements are listed.FrontierCode
- #9Epoch Capabilities Index163.4
Ranks among Noumen catalog models on Epoch AI leaderboards. Only top-20 placements are listed.Epoch AI
- #1ARC-AGI-198.5%
- #9ARC-AGI-289.2%
Ranks among Noumen catalog models on ARC Prize leaderboards. Only top-20 placements are listed.ARC Prize
- #5EQ-Bench 41310
- #12Creative Writing v31944
- #4Longform Writing83.0
- #1EQ-Bench 32096
Ranks among Noumen catalog models on EQ-Bench leaderboards. Only top-20 placements are listed.EQ-Bench
- #13Game Development1335
- #20Website1295
- #13UI Component1313
- #14Data Visualization1304
- #9SVG1300
- #163D1315
- #3ASCII Art1326
- #1Agentic Game Dev1248
- #9Web Apps1261
- #6Full Stack1280
- #1Native Apps1285
- #6Mobile Apps1263
Ranks among Noumen catalog models on Design Arena leaderboards. Only top-20 placements are listed.Design Arena
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Throughput
- 77.1 tok/s
- Faster than 51% of 256 models
- Time to first token
- 5.5 s
- Quicker than 24% of 256 models
- Prompt cache hits
- 50.9%
- About $5.42 per 1M input tokens with caching
- Request success (24h)
- 100.0%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "anthropic/claude-fable-5",
"reasoning_effort": "medium",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="anthropic/claude-fable-5",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Anthropic
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