APEX-Agents Original Effort: Max 63.6% mercor.com for Claude Fable 5 (max) on APEX-Agents Original (opens in a new tab) Archived copy (opens in a new tab) Pass rate Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on APEX-Agents Original AutomationBench 1.0.6 Effort: Low 12.5% zapier.com for Claude Fable 5 (low) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for Claude Fable 5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: Medium 13.7% zapier.com for Claude Fable 5 (medium) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for Claude Fable 5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: High 16.1% zapier.com for Claude Fable 5 (high) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for Claude Fable 5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: xHigh 15.2% zapier.com for Claude Fable 5 (xhigh) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for Claude Fable 5 on AutomationBench 1.0.6 AutomationBench 1.0.6 Effort: Max 17.1% zapier.com for Claude Fable 5 (max) on AutomationBench 1.0.6 (opens in a new tab) Archived copy (opens in a new tab) Task pass rate Reported October 7, 2026 Benchmark leaderboard Zapier Independent Zapier AutomationBench Team Record for Claude Fable 5 on AutomationBench 1.0.6 BrowseComp 130-question subset — Mercor web research agent Effort: High Configuration: Mercor web research agent, 100 steps, 3 hours 82.5% mercor.com for Claude Fable 5 (high) on BrowseComp 130-question subset — Mercor web research agent (opens in a new tab) Archived copy (opens in a new tab) BrowseComp Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on BrowseComp 130-question subset — Mercor web research agent Chartography October 2026 leaderboard Effort: Max Reported as: Adaptive/Max 34.8% surgehq.ai for Claude Fable 5 (Adaptive/Max) on Chartography October 2026 leaderboard (opens in a new tab) Archived copy (opens in a new tab) Chartography Pass@1 Reported October 7, 2026 Benchmark leaderboard Surge AI Independent Record for Claude Fable 5 on Chartography October 2026 leaderboard CharXiv Descriptive and reasoning — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 89.1% mercor.com for Claude Fable 5 (max) on CharXiv Descriptive and reasoning — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) CharXiv Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on CharXiv Descriptive and reasoning — Mercor single-shot DeepSWE 1.1 Effort: xHigh 70.0% deepswe.datacurve.ai for Claude Fable 5 (xhigh) on DeepSWE 1.1 (opens in a new tab) DeepSWE Pass@1 Reported September 22, 2026 Benchmark leaderboard Datacurve Independent Record for Claude Fable 5 on DeepSWE 1.1 DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps Effort: Max Configuration: Mercor mini-swe-agent, 500 steps, 2 hours 67.3% mercor.com for Claude Fable 5 (max) on DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps (opens in a new tab) Archived copy (opens in a new tab) DeepSWE Pass@1 Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on DeepSWE 1.1 — Mercor mini-swe-agent, 500 steps Finance Agent Benchmark 2 — October 2026 evaluation 56.3% vals.ai for Claude Fable 5 on Finance Agent Benchmark 2 — October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Finance Agent Accuracy Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on Finance Agent Benchmark 2 — October 2026 evaluation FrontierSWE 2 — October 2026 evaluation Configuration: Proximus harness, 5 trials, 20-hour budget 47.0% frontierswe.com for Claude Fable 5 on FrontierSWE 2 — October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) FrontierSWE Score Reported October 7, 2026 Benchmark leaderboard Proximal Independent Record for Claude Fable 5 on FrontierSWE 2 — October 2026 evaluation GPQA Diamond — Epoch AI harness Effort: Low Configuration: Epoch AI harness 78.8% epoch.ai for Claude Fable 5 (low) on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Evaluated August 6, 2026 at 10:17 PM UTC Benchmark leaderboard Epoch AI Independent Record for Claude Fable 5 on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness GPQA Diamond — Epoch AI harness Effort: High Configuration: Epoch AI harness 83.3% epoch.ai for Claude Fable 5 (high) on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Evaluated August 6, 2026 at 10:17 PM UTC Benchmark leaderboard Epoch AI Independent Record for Claude Fable 5 on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness GPQA Diamond — Epoch AI harness Effort: Max Configuration: Epoch AI harness 85.9% epoch.ai for Claude Fable 5 (max) on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Evaluated August 6, 2026 at 10:17 PM UTC Benchmark leaderboard Epoch AI Independent Record for Claude Fable 5 on Graduate-Level Google-Proof Q&A Diamond — Epoch AI harness GPQA Diamond — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 85.0% mercor.com for Claude Fable 5 (max) on Graduate-Level Google-Proof Q&A Diamond — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) GPQA Diamond Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on Graduate-Level Google-Proof Q&A Diamond — Mercor single-shot Humanity's Last Exam Text only — Mercor single-shot Effort: High Configuration: Mercor single-shot agent 51.5% mercor.com for Claude Fable 5 (high) on Humanity's Last Exam Text only — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Humanity's Last Exam Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on Humanity's Last Exam Text only — Mercor single-shot Humanity's Last Exam Text only — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 46.5% mercor.com for Claude Fable 5 (max) on Humanity's Last Exam Text only — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Humanity's Last Exam Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on Humanity's Last Exam Text only — Mercor single-shot MCP Atlas Public, April 2026 update 83.3% labs.scale.com for Claude Fable 5 on MCP Atlas Public, April 2026 update (opens in a new tab) Pass rate Reported September 24, 2026 Benchmark leaderboard Scale AI Independent Record for Claude Fable 5 on MCP Atlas Public, April 2026 update MedXpertQA MM — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 76.2% mercor.com for Claude Fable 5 (max) on MedXpertQA MM — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on MedXpertQA MM — Mercor single-shot MMLU-Pro Original — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 79.4% mercor.com for Claude Fable 5 (max) on MMLU-Pro Original — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on MMLU-Pro Original — Mercor single-shot MMLU-Pro Original — Vals AI harness Configuration: Vals AI harness 91.5% vals.ai for Claude Fable 5 on MMLU-Pro Original — Vals AI harness (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on MMLU-Pro Original — Vals AI harness MMMU-Pro 1,730 questions — Mercor single-shot Effort: Max Configuration: Mercor single-shot agent 72.7% mercor.com for Claude Fable 5 (max) on MMMU-Pro 1,730 questions — Mercor single-shot (opens in a new tab) Archived copy (opens in a new tab) MMMU-Pro accuracy Setting: Not stated Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on MMMU-Pro 1,730 questions — Mercor single-shot MMMU-Pro Vals AI harness Configuration: Vals AI harness 89.3% vals.ai for Claude Fable 5 on MMMU-Pro Vals AI harness (opens in a new tab) Archived copy (opens in a new tab) MMMU-Pro accuracy Setting: Standard (4 options) Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on MMMU-Pro Vals AI harness OSWorld Verified 85.0% www-cdn.anthropic.com for Claude Fable 5 on OSWorld Verified (opens in a new tab) OSWorld-Verified success rate Reported June 9, 2026 System card Anthropic Self-reported Record for Claude Fable 5 on OSWorld Verified Riemann-bench October 2026 leaderboard Effort: Max Reported as: Adaptive/Max 60.0% surgehq.ai for Claude Fable 5 (Adaptive/Max) on Riemann-bench October 2026 leaderboard (opens in a new tab) Archived copy (opens in a new tab) Riemann-bench Pass@1 Reported October 7, 2026 Benchmark leaderboard Surge AI Independent Record for Claude Fable 5 on Riemann-bench October 2026 leaderboard SimpleQA Verified Original — Epoch AI harness Effort: xHigh Configuration: Epoch AI harness 70.7% epoch.ai for Claude Fable 5 (xhigh) on SimpleQA Verified Original — Epoch AI harness (opens in a new tab) Archived copy (opens in a new tab) Accuracy Reported October 7, 2026 Evaluated August 10, 2026 at 11:44 PM UTC Benchmark leaderboard Epoch AI Independent Record for Claude Fable 5 on SimpleQA Verified Original — Epoch AI harness SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps Effort: Max Configuration: Mercor mini-swe-agent, 250 steps, 1 hour 33.1% mercor.com for Claude Fable 5 (max) on SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on SWE Atlas Codebase QnA — Mercor mini-swe-agent, 250 steps SWE Atlas Codebase QnA — Public; Claude Code Effort: xHigh Configuration: Claude Code harness 39.0% labs.scale.com for Claude Fable 5 (xHigh) on SWE Atlas Codebase QnA — Public; Claude Code (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Scale AI Independent Record for Claude Fable 5 on SWE Atlas Codebase QnA — Public; Claude Code SWE Atlas Refactoring — Claude Code Effort: xHigh Configuration: Claude Code harness 54.8% labs.scale.com for Claude Fable 5 (xHigh) on SWE Atlas Refactoring — Claude Code (opens in a new tab) Archived copy (opens in a new tab) Mean pass@1 Reported October 7, 2026 Benchmark leaderboard Scale AI Independent Record for Claude Fable 5 on SWE Atlas Refactoring — Claude Code SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps Effort: Max Configuration: Mercor mini-swe-agent, 1000 steps, 3 hours 94.8% mercor.com for Claude Fable 5 (max) on SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on SWE-bench Multilingual — Mercor mini-swe-agent, 1000 steps SWE-bench Verified 95.0% www-cdn.anthropic.com for Claude Fable 5 on SWE-bench Verified (opens in a new tab) Resolved Tasks Reported June 9, 2026 System card Anthropic Self-reported Record for Claude Fable 5 on SWE-bench Verified SWE-bench Verified — Mercor mini-swe-agent, 1000 steps Effort: Max Configuration: Mercor mini-swe-agent, 1000 steps, 3 hours 95.9% mercor.com for Claude Fable 5 (max) on SWE-bench Verified — Mercor mini-swe-agent, 1000 steps (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported October 7, 2026 Benchmark leaderboard Mercor Independent Record for Claude Fable 5 on SWE-bench Verified — Mercor mini-swe-agent, 1000 steps SWE-bench Verified — Vals AI mini-swe-agent Configuration: mini-swe-agent harness 95.0% vals.ai for Claude Fable 5 on SWE-bench Verified — Vals AI mini-swe-agent (opens in a new tab) Archived copy (opens in a new tab) Resolved Tasks Reported September 1, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on SWE-bench Verified — Vals AI mini-swe-agent Terminal-Bench 2.1 — mini-swe-agent Effort: High Configuration: mini-swe-agent harness 84.3% www-cdn.anthropic.com for Claude Fable 5 (high) on Terminal-Bench 2.1 — mini-swe-agent (opens in a new tab) Terminal-Bench Accuracy Reported June 9, 2026 System card Anthropic Self-reported Record for Claude Fable 5 on Terminal-Bench 2.1 — mini-swe-agent Terminal-Bench 4.0 — Claude Code Effort: Max Configuration: Claude Code harness 44.6% tbench.ai for Claude Fable 5 (max) on Terminal-Bench 4.0 — Claude Code (opens in a new tab) Archived copy (opens in a new tab) Terminal-Bench Accuracy Reported June 9, 2026 Benchmark leaderboard Terminal-Bench Independent Terminal-Bench Team Record for Claude Fable 5 on Terminal-Bench 4.0 — Claude Code Vals Index 2.1 61.4% vals.ai for Claude Fable 5 on Vals Index 2.1 (opens in a new tab) Archived copy (opens in a new tab) Vals Index GDP-weighted Accuracy Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on Vals Index 2.1 Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation Configuration: OpenHands harness 90.4% vals.ai for Claude Fable 5 on Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation (opens in a new tab) Archived copy (opens in a new tab) Vibe Code Bench Score Reported October 6, 2026 Benchmark leaderboard Vals AI Independent Record for Claude Fable 5 on Vibe Code Bench 1.1 — OpenHands, October 2026 evaluation τ³-bench τ³ — Banking, AllTools retrieval, v1.0.1 grading Effort: Max Configuration: AllTools retrieval 39.7% sierra-tau-bench-public.s3.us-west-2.amazonaws.com for Claude Fable 5 (max) on τ³-bench τ³ — Banking, AllTools retrieval, v1.0.1 grading (opens in a new tab) Archived copy (opens in a new tab) Task success rate Reported August 4, 2026 Evaluated July 23, 2026 Benchmark leaderboard Sierra Independent Sierra Research Record for Claude Fable 5 on τ³-bench τ³ — Banking, AllTools retrieval, v1.0.1 grading