Models / Claude Fable 5ID: anthropic/claude-fable-5
by Anthropic·via Anthropic

Claude Fable 5

Anthropic’s advanced foundation language model. Engineered for enterprise-scale conversational intelligence, complex reasoning, structured JSON schema enforcement, and generalist problem solving across a 1000K-token context window.

PlaygroundQuick Start
Maker

Anthropic

Served On

Anthropic

Architecture

Dense Transformer

Latency Profile

Fast (~380ms TTFT)

Optimized For:Structured JSON outputMulti-turn conversational reasoningTool invocationContext: 1.0M

Industry Benchmarks & Evaluations

Standard Verified Metrics
MMLU-Pro84.6%

Multi-disciplinary complex reasoning and academic evaluation.

GSM8K Math92.1%

Step-by-step mathematical reasoning and problem decomposition.

HumanEval (Coding)85.7%

Functional programming and algorithmic logic synthesis.

Chatbot Arena Elo (Est.)1310+

Blind human preference and conversational interaction quality.

Needle In A Haystack (NIAH)99.7%

Full context window retrieval accuracy across 1000K tokens.

Pricing

Rates are read live

Pricing for claude-fable-5 is fetched from the live catalogue on load, so it is never served from a cache that could outlive a repricing.

Specifications

Context window

1.0M

tokens
Max output

128K

tokens
Modality

chat

Context window, compared

claude-fable-5claude-fable-5 — 1M tokens1Mqwen-mt-turboqwen-mt-turbo — 128K tokens128Kqwen-plus-latestqwen-plus-latest — 128K tokens128Kqwen-plus-2025-01-25qwen-plus-2025-01-25 — 128K tokens128Kdeepseek-v4-pro-0813deepseek-v4-pro-0813 — 128K tokens128Kqwen3-vl-plus-2025-09-23qwen3-vl-plus-2025-09-23 — 128K tokens128Kclaude-sonnet-4-5-20250929claude-sonnet-4-5-20250929 — 1M tokens1M

Bars are scaled to 1M tokens. A model with no published context window reads Unknown, never zero.

Vision
Function calling
System prompt

Provider-Reported Capabilities

What the hosting provider reports for this model, shown as it was returned. nRouter adds nothing to this report and infers nothing that is missing from it.

Batch batch
Effort effort
Low low
Max max
High high
Xhigh xhigh
Medium medium
Thinking thinking
Types types
Enabled enabled
Adaptive adaptive
Citations citations
PDF input pdf_input
Image input image_input
Code execution code_execution
Context management context_management
Compact (2026-01-12) compact_20260112
Clear thinking (2025-10-15) clear_thinking_20251015
Clear tool uses (2025-09-19) clear_tool_uses_20250919
Structured outputs structured_outputs

Usage on nRouter

Usage is temporarily unavailable

Our aggregate read failed, so we cannot report traffic for this model right now.

nRouter SDK Integration

v2.2.1
curl https://api.nrouter.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${NROUTER_API_KEY}" \
  -d '{
    "model": "anthropic/claude-fable-5",
    "messages": [
      {
        "role": "system",
        "content": "You are a helpful assistant powered by claude-fable-5 via nRouter."
      },
      {
        "role": "user",
        "content": "Explain distributed consensus algorithms."
      }
    ]
  }'

Availability

Availability is temporarily unavailable

Our own telemetry read failed, so we cannot report uptime or latency for this model right now. This says nothing about the model itself — it is not an outage, and we would rather show you nothing than a figure we did not measure.

Interactive Playground

Send a real test request to claude-fable-5 using your virtual key.

Test it

Prompt
cURL
curl https://api.nrouter.ai/v1/chat/completions \
  -H "Authorization: Bearer $NROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"anthropic/claude-fable-5","messages":[{"role":"user","content":"Hello!"}]}'

Managed Gateway Routing

Unified single-key access with automatic multi-region fallback, real-time credit enforcement, and sub-millisecond routing latency.

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