Claude Fable 5

Type: AI model

Claude Fable 5 is Anthropic’s flagship fifth-generation Claude model, released June 2026 as the publicly available, safety-gated counterpart to the partner-restricted Mythos 5. It posts state-of-the-art results on agentic coding and science benchmarks, including roughly 80% on SWE-Bench Pro. GROUNDING tracks Claude Fable 5 releases, benchmarks, safety guardrails, and developer-facing capabilities.

Recent Updates

• 2026-07-17: Mermaid to ASCII art tool compiled to WebAssembly (Simon Willison’s Weblog) · simonwillison.net — Simon Willison’s Weblog AlexanderGrooff/mermaid-ascii Grok Build Simon Willison
• 2026-07-17: Moonshot AI launches Kimi K3 as a 2.8T open-weights model with 1M context (Latent.Space) · latent.space — Long Context Code Agents Agents Moonshot AI · z.ai · Latent Space · AINews · Arena · Artificial Analysis SimonW Jianlin_S Yulun_Du scaling01 eliebakouch kimmonismus nrehiew_ · Kimi K3 · GPT-5.6 Sol · Opus 4.8 · kimi-k2.6 · GPT 5.5
• 2026-07-17: Kimi K3 posts benchmark gains and Moonshot AI signals open-weight release (Kimi.ai) · x.com — LLM Evals Agents Tool Use Kimi.ai · Artificial Analysis · Moonshot AI · Zapier · Kimi K3 · Opus 4.8 · GPT 5.5 · Fable 5 · GPT-5.6 Sol · K2.6 · GLM-5.2 · Claude Opus 4.8
• 2026-07-17: Moonshot AI launches Kimi K3 with high pricing and benchmark claims (Hacker News) · simonwillison.net — LLM Evals Tool Use Moonshot AI · Artificial Analysis · OpenRouter · Anthropic · OpenAI Arena.ai · Kimi K3 · kimi-k2.6 · Claude Opus 4.8 Max · GPT 5.5 high · GPT-5.6 Sol · GLM-5.2 · Gemini
• 2026-07-18: Latent Space roundup: Kimi K3, Databricks funding, and agent sandbox infrastructure (Latent.Space) · latent.space — Latent.Space · AINews · Databricks · OpenRouter · Moonshot · ChatGPT · e2b Daytona · Modal AIE NYC Abhishek Bhardwaj Greg Brockman Alex Atallah Zhilin Yang Salakhutdinov kimmonismus AnikaSomaia dylan522p novasarc01 scaling01 theo hqmank · Kimi K3 · Opus 4.8 · GPT-5.6 Terra · GPT 5.5 · GPT-5.6 Sol
• 2026-07-18: Claude Fable 5 stays in subscription plans (Simon Willison’s Weblog) · simonwillison.net — Anthropic · Claude.ai Simon Willison · GPT-5.6 Sol Kimi 3
• 2026-07-18: Kimi.ai reposts a Kimi K3 vs. Claude Fable 5 software engineering benchmark claim (Kimi.ai) · x.com — LLM Evals Kimi.ai togethercompute · Kimi K3
• 2026-07-18: Kimi K3 vs. Claude Fable 5 compared on software engineering tasks (Kimi.ai) · x.com — LLM Evals Kimi.ai togethercompute · Kimi K3
• 2026-07-19: A postmortem on using multiple AI subscriptions to reduce research token burn (Hacker News) · quesma.com — Agents Context Engineering Tool Use MCP Quesma Claude · Codex · Antigravity claude-mem Terminal-Bench · SWE-Bench Pro · Artificial Analysis Claude Max 5x · Claude Opus 4.8 · Claude Sonnet 5 · GPT 5.5 · Gemini-3.1-Pro
• 2026-07-20: Kimi K3 is presented as an open-weights frontier model (Interconnects AI) · interconnects.ai — Open Source LLMs LLM Evals Interconnects AI Moonshot AI · Anthropic · OpenAI · SpaceXAI · xAI Zhipu (Z.ai) · Meta · DeepMind · Alibaba Vals AI · Artificial Analysis Frontend Code Arena · Kimi K3 · DeepSeek R1 · GPT-5.6 Sol · Grok 4.5 · GLM-5.2 · Muse Spark 1.1 Gemini Flash 3.5 · Qwen 3.7 Max Qwen 3.8
• 2026-07-21: Laguna S 2.1 targets long-horizon agentic coding with 1M-token context (Hacker News) · poolside.ai — Agents Code Agents LLM Evals Long Context Tool Use Poolside · Datacurve · Tencent · Laguna S 2.1 Laguna M.1 XS.2 DeepSWE Terminal-Bench 2.1 SWE-bench Multilingual · SWE-bench Pro SWE Atlas Toolathlon Verified Tencent Hy3 · Inkling · Nemotron 3 Ultra · DeepSeek-V4-Pro-Max · Kimi K3 · Qwen 3.7 Max · Muse Spark 1.1
• 2026-07-21: Hacker News post on drawing benchmarks for frontier vision models (Hacker News) · tryai.dev — LLM Evals Tool Use Hacker News · GitHub · GPT-5.6 Sol · Grok 4.5 · Gemini 3.6 Flash
• 2026-07-22: Kimi K3 ranks near the top on Artificial Analysis’ AA-Briefcase benchmark (Kimi.ai) · x.com — LLM Evals Agents Kimi.ai ArtificialAnlys Kimi_Moonshot · Artificial Analysis · Kimi K3 · kimi-k2.6 · Opus 4.8 · GPT 5.5
• 2026-07-22: Structured output changes answer diversity across 44 language models (cs.CL updates on arXiv.org) · arxiv.org
• 2026-07-22: Kimi K3 ranks second on AA-Briefcase but is costly and slow per task (Hacker News) · artificialanalysis.ai — Agents LLM Evals Moonshot AI · Artificial Analysis · Kimi K3 · kimi-k2.6 · GPT-5.6 Sol · Claude Sonnet 5 · Claude Opus 4.8 · GPT 5.5 · Grok 4.5 · Gemini 3.6 Flash · Gemini 3.5 Flash-Lite
• 2026-07-22: Testing Whether AI Labs Are Optimizing for the Pelican Benchmark (Hacker News) · dylancastillo.co — LLM Evals OpenRouter · GitHub · Hacker News Simon Willison · GPT-5.6 Terra · Claude Sonnet 5 · Gemini 3.5 Flash · Grok 4.5 · Qwen3.7-Max · GLM-5.2 · DeepSeek V4 Pro · GPT-5.6 Luna Gemini 3.1 Flash-Lite
• 2026-07-22: US Treasury scrutiny of Chinese AI collides with Nvidia’s pro-open-model stance (Все статьи подряд / Искусственный интеллект / Хабр) · habr.com — Open Source LLMs Fox Business Axios · NVIDIA · Moonshot AI · Claude · Anthropic Project Glasswing · Microsoft · Apple · AWS · Linux Foundation · OpenAI Scott Bessent Jensen Huang · Kimi K3 · GPT-5.6 Sol · Opus 4.8 · Claude Mythos · DeepSeek R1
• 2026-07-23: Startups ask Trump not to cut off access to Chinese open-weight AI models (Hacker News) · politico.com — Open Source LLMs Proton · Y Combinator Little Tech Association · Moonshot AI · Alibaba · Anthropic · OpenAI · White House Commerce Department Treasury Office of Science and Technology Policy Donald Trump Scott Bessent Howard Lutnick · Kimi K3
• 2026-07-23: Design Arena analyzes why GPT-5.6 Sol and Kimi K3 produce stronger UI designs (Искусственный интеллект – AI, ANN и иные формы искусственного разума) · habr.com — LLM Evals Agents Design Arena OpenAI · Moonshot AI · Anthropic · GPT-5.6 Sol · Kimi K3 · GLM-5.2 · GPT 5.5 · kimi-k2.6 · Kimi-K2.7-Code
• 2026-07-24: ActiveVision benchmark shows multimodal models struggle with multi-step visual inspection (alphaXiv) · x.com — LLM Evals alphaXiv · OpenAI · Anthropic · GPT 5.5
• 2026-07-24: ActiveVision benchmarks active observation in multimodal LLMs (alphaXiv) — LLM Evals Jiarui Zhang Muzi Tao Shangshang Wang Ollie Liu Xuezhe Ma Willie Neiswanger GPT 5.5
• 2026-07-24: Anthropic introduces Claude Opus 5 (ElKornacio) · anthropic.com — Code Agents Agents LLM Evals Anthropic · Zapier · Claude Opus 5 · Mythos 5 · Opus 4.8 Claude Max Claude Pro
• 2026-07-24: Claude Opus 5 launches with stronger coding and knowledge-work benchmark results (Hacker News) · anthropic.com — Agents Code Agents LLM Evals Claude Opus 5 · Mythos 5 · Opus 4.8
• 2026-07-24: Opus 5 tops the Artificial Analysis Intelligence Leaderboard (Hacker News) · artificialanalysis.ai — LLM Evals Agents Tool Use Code Agents Long Context Artificial Analysis · Claude Opus 5 · GPT-5.6 Sol Mercury 2 HyperNova 60B 2605 Granite 4.0 H Small Gemma 3n E4B Instruct Nova Micro Sarvam 30B · Gemini 2.5 Flash Lite · Command A+ · Gemini 2.5 Flash · GLM-5.2 · MiniMax M3 · DeepSeek V4 Pro
• 2026-07-25: Claude Code trims system prompts as context engineering shifts (Hacker News) · claude.com — Context Engineering Code Agents Tool Use LLM Evals Claude Opus 5

FAQ

What is Claude Fable 5?

Claude Fable 5 is Anthropic’s flagship fifth-generation Claude model, released June 2026 as the publicly available, safety-gated counterpart to the partner-restricted Mythos 5. It posts state-of-the-art results on agentic coding and science benchmarks, including roughly 80% on SWE-Bench Pro. GROUNDING tracks Claude Fable 5 releases, benchmarks, safety guardrails, and developer-facing capabilities.

What does this page track?

Dated radar mentions, source links, related concepts, and builder-relevant context for Claude Fable 5, collected automatically by GROUNDING.

When was Claude Fable 5 last mentioned?

Claude Fable 5 was most recently mentioned in a radar update dated 2026-07-25.

Category: Text / Language Models