--- title: claude-fable-5-1 API — Claude Pricing & Specs | RunAPI description: Use claude-fable-5-1 via RunAPI — the Claude family. Per-call pricing, model ID, specs, and developer setup guide. url: https://runapi.ai/models/claude/fable-5-1.md canonical: https://runapi.ai/models/claude/fable-5-1 locale: en site: RunAPI image: https://runapi.ai/assets/opengraph-f702f2b1.png alternates: en: https://runapi.ai/models/claude/fable-5-1 zh-CN: https://runapi.ai/zh-CN/models/claude/fable-5-1 es: https://runapi.ai/es/models/claude/fable-5-1 ja: https://runapi.ai/ja/models/claude/fable-5-1 de: https://runapi.ai/de/models/claude/fable-5-1 fr: https://runapi.ai/fr/models/claude/fable-5-1 pt-BR: https://runapi.ai/pt-BR/models/claude/fable-5-1 ko: https://runapi.ai/ko/models/claude/fable-5-1 it: https://runapi.ai/it/models/claude/fable-5-1 nl: https://runapi.ai/nl/models/claude/fable-5-1 pl: https://runapi.ai/pl/models/claude/fable-5-1 tr: https://runapi.ai/tr/models/claude/fable-5-1 zh-TW: https://runapi.ai/zh-TW/models/claude/fable-5-1 zh-HK: https://runapi.ai/zh-HK/models/claude/fable-5-1 ar: https://runapi.ai/ar/models/claude/fable-5-1 x-default: https://runapi.ai/models/claude/fable-5-1 model: Claude provider: Anthropic variant_id: claude-fable-5-1 sdk_model_id: claude-fable-5-1 modality: text billing_unit: 1K tokens status: active --- > HTML version: https://runapi.ai/models/claude/fable-5-1 > Site index for agents: https://runapi.ai/llms.txt # claude-fable-5-1 API Use claude-fable-5-1 from the Claude family via RunAPI. Per-call pricing, no subscription, and failed generations are never charged. **Anthropic / [Claude](https://runapi.ai/models/claude.md)** **Operational · text · Commercial OK** claude-fable-5-1 targets the sweet spot of quality and cost within the Claude family. It shares the same API key, request shape, and async task lifecycle as every other RunAPI model — switch to this variant by changing one model ID parameter. Install the Claude skill to load docs, typed schemas, pricing notes, and setup steps into your coding workspace. Billing is metered per completed request in USD with no subscription or minimum spend, and failed generations are never charged. - Pay-per-call pricing in USD with no subscription - Failed generations are never charged - Streaming when supported by the model - Schema-validated parameters and tool calls - Switch variant by changing one model ID parameter - Unified billing across all models and providers ## Pricing ### `message` - Input: $10.00 / 1M tokens - Output: $50.00 / 1M tokens - Cache read: $0.25 / 1M tokens - Cache write 5m: $12.50 / 1M tokens - Cache write 1h: $20.00 / 1M tokens Failed generations are not charged ## Technical details | Field | Value | |---|---| | Model ID | `claude-fable-5-1` | | Provider | Anthropic | | Modality | text | | Task type | synchronous | | Billing unit | 1K tokens | | API endpoint | `/v1/chat/completions` | | | `/v1/responses` | | | `/v1/messages` | | | `/v1beta/models/claude-fable-5-1:generateContent` | | | `/v1beta/models/claude-fable-5-1:streamGenerateContent` | | Commercial license | Yes — included via API | | Catalog status | Operational | **Request example** ```json { "model": "claude-fable-5-1", "max_tokens": 1024, "messages": [ { "role": "user", "content": "Review this pull request for security vulnerabilities, performance issues, and suggest concrete improvements." } ] } ``` ## Model skill — claude-fable-5-1 Install the skill once, then use the variant ID from this page while building. Base URL: `https://runapi.ai` | Endpoint | Protocol | |---|---| | `POST /v1/chat/completions` | OpenAI compatible | | `POST /v1/responses` | OpenAI Responses | | `POST /v1/messages` | Anthropic compatible | | `POST /v1beta/models/claude-fable-5-1:generateContent` | Gemini generateContent | | `POST /v1beta/models/claude-fable-5-1:streamGenerateContent` | Gemini streamGenerateContent | Use the OpenAI or Anthropic SDK with your RunAPI API key and `model: "claude-fable-5-1"`. ## Use claude-fable-5-1 with a model skill 1. **Install** — Install the model skill for the Claude line. The skill loads docs, typed schemas, pricing notes, and setup steps into your coding workspace so your agent has the right context. 2. **Configure** — Set the model field to the full model ID shown on this page and configure your RunAPI API key as an environment variable. The same key works across all models and providers. 3. **Call** — Use the skill instructions while adding prompt, input, and callback handling to your application. RunAPI routes the request to the provider, manages the async lifecycle, and returns structured JSON. 4. **Receive** — Read the task response by polling the task ID, streaming when supported, or handling the webhook callback at your configured URL. Generated outputs are stored and retrievable by task ID. ## What's different about claude-fable-5-1 - **VS CLAUDE-FABLE-5: 1M context; Fable 5 successor with 75% cheaper cache reads** — Mythos-class 1M context; state-of-the-art coding, reasoning, and vision - **VS CLAUDE-HAIKU-4-5-20251001: 1M context; Fable 5 successor with 75% cheaper cache reads** — Haiku 4.5 for reproducible outputs - **VS CLAUDE-OPUS-4-1-20250805: 1M context; Fable 5 successor with 75% cheaper cache reads** — claude-opus-4-1-20250805 ## Best for - **Customer support** — Answer customer questions from a private knowledge base, reducing ticket volume. - **Document analysis** — Draft contract summaries and flag key clauses for attorney review. - **Code generation** — Auto-generate unit tests, code reviews, and refactoring suggestions in CI. ## Frequently asked questions about claude-fable-5-1 ### How do I select claude-fable-5-1? Pass the model ID shown in the quickstart. ### What's the rate limit on this variant? Per-key rate limits scale with your usage tier. The pricing page shows current limits. If you need higher throughput, contact support to discuss tier upgrades. ### Can I switch variants later? Yes. Variant is a parameter in the request. Switch by changing the model ID — no code changes, no re-authentication, no separate billing setup. All variants share the same API key and request shape. ### Does it stream? Where streaming is available, RunAPI streams end-to-end. LLM models support token-level streaming. Media models use async task polling or webhook callbacks for result delivery. ### Where do I report quality issues? Open an issue on the public GitHub repo or email support at support@runapi.ai. Include the task ID and model ID so the team can investigate the specific generation. ### Do I need a separate provider account? No. Your RunAPI API key is enough to access this variant and every other model in the catalog. You do not need accounts with the underlying provider. ### Other variants of Claude - [claude-fable-5](https://runapi.ai/models/claude/fable-5.md) — `claude-fable-5` · Input $10.00 / 1M tokens | Output $50.00 / 1M tokens - [claude-haiku-4-5-20251001](https://runapi.ai/models/claude/haiku-4-5-20251001.md) — `claude-haiku-4-5-20251001` · Input $0.60 / 1M tokens | Output $3.00 / 1M tokens - [claude-opus-4-1-20250805](https://runapi.ai/models/claude/opus-4-1-20250805.md) — `claude-opus-4-1-20250805` · Input $9.00 / 1M tokens | Output $45.00 / 1M tokens - [claude-opus-4-5-20251101](https://runapi.ai/models/claude/opus-4-5-20251101.md) — `claude-opus-4-5-20251101` · Input $3.00 / 1M tokens | Output $15.00 / 1M tokens - [claude-opus-4-6](https://runapi.ai/models/claude/opus-4-6.md) — `claude-opus-4-6` · Input $3.00 / 1M tokens | Output $15.00 / 1M tokens - [claude-opus-4-7](https://runapi.ai/models/claude/opus-4-7.md) — `claude-opus-4-7` · Input $3.00 / 1M tokens | Output $15.00 / 1M tokens - [claude-opus-4-8](https://runapi.ai/models/claude/opus-4-8.md) — `claude-opus-4-8` · Input $3.00 / 1M tokens | Output $15.00 / 1M tokens - [claude-opus-5](https://runapi.ai/models/claude/opus-5.md) — `claude-opus-5` · Input $3.00 / 1M tokens | Output $15.00 / 1M tokens - [claude-sonnet-4-5-20250929](https://runapi.ai/models/claude/sonnet-4-5-20250929.md) — `claude-sonnet-4-5-20250929` · Input $1.80 / 1M tokens | Output $9.00 / 1M tokens - [claude-sonnet-4-6](https://runapi.ai/models/claude/sonnet-4-6.md) — `claude-sonnet-4-6` · Input $1.80 / 1M tokens | Output $9.00 / 1M tokens - [claude-sonnet-5](https://runapi.ai/models/claude/sonnet-5.md) — `claude-sonnet-5` · Input $1.36 / 1M tokens | Output $6.78 / 1M tokens ### Alternatives from other models - [DeepSeek](https://runapi.ai/models/deepseek.md) — DeepSeek API access via RunAPI — flash for fast, low-cost work; pro for complex agentic tasks. - [Embedding](https://runapi.ai/models/embedding.md) — OpenAI text embeddings for semantic search, retrieval, clustering, and ranking workflows. - [Gemini](https://runapi.ai/models/gemini.md) — Gemini API access for Google's multimodal LLM across chat, code generation, reasoning, and long-context tasks. ## Start building with Claude. - [Create free account](https://runapi.ai/login) - [Read the quickstart →](https://runapi.ai/docs/api/anthropic/messages) --- ## More from RunAPI - [Home](https://runapi.ai/.md) - [Models](https://runapi.ai/models.md) - [AI Video API Comparison](https://runapi.ai/ai-video-api-comparison.md) - [OpenClaw Integration](https://runapi.ai/openclaw.md) - [Best API for OpenClaw](https://runapi.ai/best-api-for-openclaw.md) - [OpenClaw Image Generation](https://runapi.ai/openclaw-image-generation.md) - [Hermes Agent Integration](https://runapi.ai/hermes-agent.md) - [Pricing](https://runapi.ai/pricing.md) - [Claude API Pricing](https://runapi.ai/claude-api-pricing.md) - [ChatGPT API Pricing](https://runapi.ai/chatgpt-api-pricing.md) - [OpenAI API Pricing](https://runapi.ai/openai-api-pricing.md) - [Gemini API Pricing](https://runapi.ai/gemini-api-pricing.md) - [Claude Code Pricing](https://runapi.ai/claude-code-pricing.md) - [Claude Code API](https://runapi.ai/claude-code-api.md) - [Claude Code vs Cursor](https://runapi.ai/claude-code-vs-cursor.md) - [Claude Max vs API](https://runapi.ai/claude-max-vs-api.md) - [Requesty Alternative](https://runapi.ai/requesty-alternative.md) - [Docs](https://runapi.ai/docs/guides) - [SDK](https://runapi.ai/sdk.md) - [Skills](https://runapi.ai/skills.md) - [MCP Server](https://runapi.ai/mcp.md) - [CLI](https://runapi.ai/cli.md) - [Feedback](https://runapi.makethisbetter.dev) - [Contact](mailto:support@runapi.ai) - [Terms](https://runapi.ai/terms.md) - [Privacy](https://runapi.ai/privacy.md) - [Site index for agents](https://runapi.ai/llms.txt) Contact: contact@runapi.ai ## Structured data ```json [ { "@context": "https://schema.org", "inLanguage": "en", "@type": "WebSite", "name": "RunAPI", "url": "https://runapi.ai/", "potentialAction": { "@type": "SearchAction", "target": { "@type": "EntryPoint", "urlTemplate": "https://runapi.ai/models?q={search_term_string}" }, "query-input": "required name=search_term_string" } }, { "@context": "https://schema.org", "inLanguage": "en", "@type": "Organization", "name": "RunAPI", "url": "https://runapi.ai/", "logo": { "@type": "ImageObject", "url": "https://runapi.ai/icon.svg" }, "sameAs": [ "https://github.com/runapi-ai" ] }, { "@context": "https://schema.org", "inLanguage": "en", "@type": "SoftwareApplication", "name": "Claude claude-fable-5-1", "applicationCategory": "DeveloperApplication" }, { "@context": "https://schema.org", "inLanguage": "en", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://runapi.ai/" }, { "@type": "ListItem", "position": 2, "name": "Models", "item": "https://runapi.ai/models" }, { "@type": "ListItem", "position": 3, "name": "Claude", "item": "https://runapi.ai/models/claude" }, { "@type": "ListItem", "position": 4, "name": "claude-fable-5-1", "item": "https://runapi.ai/models/claude/fable-5-1" } ] }, { "@context": "https://schema.org", "inLanguage": "en", "@type": "HowTo", "name": "Use claude-fable-5-1 with a model skill", "description": "Use claude-fable-5-1 via RunAPI — the Claude family. Per-call pricing, model ID, specs, and developer setup guide.", "totalTime": "PT5M", "step": [ { "@type": "HowToStep", "position": 1, "name": "Install", "text": "Install the model skill for the Claude line. The skill loads docs, typed schemas, pricing notes, and setup steps into your coding workspace so your agent has the right context.", "url": "https://runapi.ai/models/claude/fable-5-1#how-step-1" }, { "@type": "HowToStep", "position": 2, "name": "Configure", "text": "Set the model field to the full model ID shown on this page and configure your RunAPI API key as an environment variable. The same key works across all models and providers.", "url": "https://runapi.ai/models/claude/fable-5-1#how-step-2" }, { "@type": "HowToStep", "position": 3, "name": "Call", "text": "Use the skill instructions while adding prompt, input, and callback handling to your application. RunAPI routes the request to the provider, manages the async lifecycle, and returns structured JSON.", "url": "https://runapi.ai/models/claude/fable-5-1#how-step-3" }, { "@type": "HowToStep", "position": 4, "name": "Receive", "text": "Read the task response by polling the task ID, streaming when supported, or handling the webhook callback at your configured URL. Generated outputs are stored and retrievable by task ID.", "url": "https://runapi.ai/models/claude/fable-5-1#how-step-4" } ] }, { "@context": "https://schema.org", "inLanguage": "en", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "How do I select claude-fable-5-1?", "acceptedAnswer": { "@type": "Answer", "text": "Pass the model ID shown in the quickstart." } }, { "@type": "Question", "name": "What's the rate limit on this variant?", "acceptedAnswer": { "@type": "Answer", "text": "Per-key rate limits scale with your usage tier. The pricing page shows current limits. If you need higher throughput, contact support to discuss tier upgrades." } }, { "@type": "Question", "name": "Can I switch variants later?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. Variant is a parameter in the request. Switch by changing the model ID — no code changes, no re-authentication, no separate billing setup. All variants share the same API key and request shape." } }, { "@type": "Question", "name": "Does it stream?", "acceptedAnswer": { "@type": "Answer", "text": "Where streaming is available, RunAPI streams end-to-end. LLM models support token-level streaming. Media models use async task polling or webhook callbacks for result delivery." } }, { "@type": "Question", "name": "Where do I report quality issues?", "acceptedAnswer": { "@type": "Answer", "text": "Open an issue on the public GitHub repo or email support at support@runapi.ai. Include the task ID and model ID so the team can investigate the specific generation." } }, { "@type": "Question", "name": "Do I need a separate provider account?", "acceptedAnswer": { "@type": "Answer", "text": "No. Your RunAPI API key is enough to access this variant and every other model in the catalog. You do not need accounts with the underlying provider." } } ] } ] ```