claude-fable-5 — API, Pricing & Context Window | Vivgrid

claude-fable-5 opened Anthropic's Fable tier — the frontier above Opus — for demanding reasoning and long-running agentic workloads. It offers a 1M-token context window, 128K-token max output, and always-on adaptive thinking, at the same per-token price as its successor claude-fable-5-1.

On Vivgrid, claude-fable-5 is served through the native Messages API (/messages) with geo-distributed acceleration across AMER, EMEA, and APAC, reachable with the same unified API key as the rest of the catalog.

Specifications

Pricing

Pricing in USD per 1M tokens, matching the provider's rates.

Quick start

Call claude-fable-5 through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the Vivgrid Console.

curl https://api.vivgrid.com/v1/messages \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-fable-5",
    "max_tokens": 1024,
    "messages": [
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }
    ],
    "stream": true
  }'

Prompt caching is billed at $12.50 per 1M cache-write tokens on the 5-minute TTL and $20.00 per 1M on the 1-hour TTL, with cached reads at $1.25.

Ideal use cases

• Frontier coding agents and autonomous software development
• Long-context analysis and refactoring within a 1M-token budget
• Complex planning and reasoning across long agent sessions
• Workloads already tuned for Fable-tier behavior

Related models

• claude-fable-5-1 — the newer Fable release with cheaper cache reads
• claude-opus-5 — the Opus-tier model at half the price
• claude-sonnet-5 — a faster, lower-cost Claude model