Claude Fable 5

Name: Claude Fable 5 API
Brand: Anthropic
SKU: claude-fable-5
Price: 3.5 USD
Availability: InStock

The previous Fable, for long-running agentic work.

claude-fable-5Get API key

Pricing USD per million tokens

Tokens	Per 1M tokens
Input	$3.50
Cached input	$0.35
Cache write (5 min)	$4.375
Cache write (1 hour)	$7.00
Output	$17.50

Reasoning tokens are billed as output. Each answer's usage carries cost_usd, the amount taken from your balance; a request with no answer costs $0.00.

Request

curl

curl https://api.revana.si/v1/chat/completions \
  -H "Authorization: Bearer $REVANA_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"claude-fable-5","messages":[{"role":"user","content":"Write a haiku about routing."}]}'

Python

import os
from openai import OpenAI

client = OpenAI(base_url="https://api.revana.si/v1", api_key=os.environ["REVANA_API_KEY"])
reply = client.chat.completions.create(
    model="claude-fable-5",
    messages=[{"role": "user", "content": "Write a haiku about routing."}],
)
print(reply.choices[0].message.content)

Any OpenAI SDK works: set the base URL to https://api.revana.si/v1. Streaming, tools and the rest are in the chat completions docs.

Details

Model id

claude-fable-5

Maker

Anthropic

Endpoint

POST /v1/chat/completions

Context window

1M tokens

Max output

128K tokens

Streaming

Yes (server-sent events)

Routes

2 (falls back automatically)

2 routes

Every request starts on the cheapest route. A busy or failed route hands it to the next before any answer is sent.

About the Claude Fable 5 API

How much does the Claude Fable 5 API cost?

Claude Fable 5 costs $3.50 per million input tokens, $0.35 per million cached input tokens and $17.50 per million output tokens on Revana. You pay from prepaid credit for the tokens each request used, with no subscription or minimum.

How do I call Claude Fable 5 from code?

Use any OpenAI SDK with base URL https://api.revana.si/v1 and your Revana API key, and set model to "claude-fable-5". POST /v1/chat/completions takes the OpenAI request body, streamed or not.

What happens if a request fails?

Revana has 2 routes for Claude Fable 5 and moves a request to the next one when a route is busy or down. A request that gets no answer costs nothing.

Is Claude Fable 5 on Revana the same model?

Yes. Revana passes your request to Anthropic's model unchanged and returns its answer in the OpenAI format, with the usage it reported and what the request cost.