Anthropic: Claude Fable 5.1

Name: Claude Fable 5.1
Brand: Anthropic
Price: 1073.3 RUB
Availability: InStock

anthropic/claude-fable-5.1

textVisionFilesReasoning

Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual code generation, and finance and analysis tasks in particular. It also tends to be more concise than Fable 5 in its plans and summaries. We recommend testing it as a direct upgrade wherever you use Fable 5 today, and alongside Opus 5 on reasoning-heavy tasks. 1M context, image and file input.

Price in / out

Cache, read / write

Context / Max output

1M / 128K

Released

Sep 1, 2026

Additional rates

Web search

Parameters

messagesrequired

reasoning_effortlow · medium · high · xhigh · max

max_tokensoptional · alias max_completion_tokens

streamtrue · false

toolsfunction calling (OpenAI format)

response_formatjson_object · json_schema

web_search · · ·

providerrouting: order · only · ignore · sort

stream_options{"include_usage": true}

image_urlimage (data: URL)

filePDF · DOCX · TXT · CSV · XLSX · PPTX (data: URL)

Fine-tuning · 1

stopoptional

How to use via API

from openai import OpenAI

client = OpenAI(base_url="https://api.mixen.ai/v1", api_key="mxn-...")
resp = client.chat.completions.create(
    model="anthropic/claude-fable-5.1",
    messages=[{"role": "user", "content": "Привет"}],
    reasoning_effort="low",  # low · medium · high · xhigh · max
    max_tokens=1024,
    stream=False,
)
print(resp.choices[0].message.content)

# Стриминг: stream=True — ответ приходит чанками
for chunk in client.chat.completions.create(
    model="anthropic/claude-fable-5.1",
    messages=[{"role": "user", "content": "Привет"}],
    stream=True,
):
    print(chunk.choices[0].delta.content or "", end="", flush=True)

# с файлом (PDF · DOCX · TXT · CSV · XLSX · PPTX)
doc = client.chat.completions.create(
    model="anthropic/claude-fable-5.1",
    messages=[{"role": "user", "content": [
        {"type": "text", "text": "Кратко перескажи документ"},
        {"type": "file", "file": {
            "filename": "doc.pdf",
            "file_data": "data:application/pdf;base64,JVBERi0...",
        }},
    ]}],
)

API docsTry in the bot

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