Benchmark Almanac

SWE-Together

Claude Fable 5.1 69.3% leads since September 2026
Not in model cards

Coding agents work through 109 repository tasks rebuilt from real multi-turn sessions between users and coding agents. A simulated user replays the original user's goals and gives feedback when the agent needs it. Scores count tasks solved and the number of corrections the user had to make.

Tasks come from 11,260 recorded sessions. The makers' leaderboard runs 23 models in one harness (opencode) with two trials each. Five entries are paper results that were not rerun. A judge score of 0.85 or more counts as a solve. About 86 GitHub stars.

Made by
Meta
Released
June 2026
Kind
Fixing real repositories
Level
Expert
Scored
Graded by a model
Answers
Agent task
Tasks
All public
Strongest model tested
GPT-6 Astra #3 on the capability index
Last model added
September 2026
Scores refreshed
November 12th, 2026

In the authors’ words

Most coding-agent benchmarks are static: an agent receives a complete task description up front and is judged only by its final code. Real coding assistance is interactive, with users clarifying goals, adding constraints, and correcting mistakes over multiple turns. We introduce SWE-Together, a multi-turn benchmark reconstructed from real user-agent coding sessions. To make real interactions verifiable, we curate 109 repository-level tasks from 11,260 recorded sessions, selecting sessions with recoverable repository states, clear user goals, and observable outcomes. To replay these interactions across agents, we build a reactive LLM-based user simulator that preserves the original users' intents and provides feedback when the coding agent's progress requires it. To evaluate agents as collaborators, we measure both final repository correctness and the number of corrective feedback turns required during the interaction. Experiments with frontier coding agents show that stronger agents generally achieve higher final success rates while requiring fewer interventions, suggesting an improved user experience.

Abstract of SWE-Together: Evaluating Coding Agents in Interactive User Sessions (arXiv:2606.29957, CC0)
23
Entries on its own leaderboard, 22 models we track

Claude Fable 5.1 leads with 69.3%

Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Every run is in the next chart. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders.

  1. 1 Claude Fable 5.1 69.3%
  2. 2 Claude Fable 5 68.8%
  3. 3 Claude Opus 5.5 68.8%
  4. 4 Grok 4.7 65.1%
  5. 5 Gemini 3.8 Flash 64.2%
  6. 6 Kimi K3 63.8%
  7. 7 Claude Opus 5 63.8%
  8. 8 Claude Opus 4.6 62.4%
  9. 9 Muse Spark 1.3 62.4%
  10. 10 Claude Sonnet 5.5 62.4%
  11. 11 Claude Opus 4.7 61.5%
  12. 12 Claude Opus 4.8 61.5%
  13. 13 Grok 4.6 60.6%
  14. 14 GPT-6 Astra 60.6%
  15. 15 GPT-6 Sol 60.6%
  16. 16 GPT-6 Luna 59.6%
  17. 17 GPT-6.1 Sol 58.3%
  18. 18 GPT-5.5 58%
  19. 19 GPT-5.6 Sol 57.8%
  20. 20 GLM-5.2 55%
  21. 21 GLM-5.1 52%
  22. 22 DeepSeek-V4-Pro 48%
  23. 23 minimax-2.7 39%

Source: Official SWE-Together leaderboard

#EntryScoreSettingDateSource
1 Claude Fable 5.1 69.3% opencode Sep 2026 Official leaderboard
2 Claude Fable 5 68.8% opencode Jun 2026 Official leaderboard
3 Claude Opus 5.5 68.8% opencode Sep 2026 Official leaderboard
4 Grok 4.7 65.1% opencode Sep 2026 Official leaderboard
5 Gemini 3.8 Flash 64.2% opencode Sep 2026 Official leaderboard
6 Kimi K3 63.8% opencode Jul 2026 Official leaderboard
7 Claude Opus 5 63.8% opencode Jul 2026 Official leaderboard
8 Claude Opus 4.6 62.4% opencode Feb 2026 Official leaderboard
9 Muse Spark 1.3 62.4% opencode Sep 2026 Official leaderboard
10 Claude Sonnet 5.5 62.4% opencode Sep 2026 Official leaderboard
11 Claude Opus 4.7 61.5% opencode Apr 2026 Official leaderboard
12 Claude Opus 4.8 61.5% opencode May 2026 Official leaderboard
13 Grok 4.6 60.6% opencode Aug 2026 Official leaderboard
14 GPT-6 Astra 60.6% opencode Sep 2026 Official leaderboard
15 GPT-6 Sol 60.6% opencode Sep 2026 Official leaderboard
16 GPT-6 Luna 59.6% opencode Sep 2026 Official leaderboard
17 GPT-6.1 Sol 58.3% opencode Sep 2026 Official leaderboard
18 GPT-5.5 58% opencode Apr 2026 Official leaderboard
19 GPT-5.6 Sol 57.8% opencode Jul 2026 Official leaderboard
20 GLM-5.2 55% opencode Jun 2026 Official leaderboard
21 GLM-5.1 52% opencode Apr 2026 Official leaderboard
22 DeepSeek-V4-Pro 48% opencode Apr 2026 Official leaderboard
23 minimax-2.7 39% opencode Official leaderboard

The best score, 69.3%, costs $8.19 a task

Runs on the cost frontier score higher than any run that's cheaper. The costs are the leaderboard's own estimates, so compare them only within this benchmark.

Anthropic Google DeepMind OpenAI Cost frontier One model at each effort level
0% 20% 40% 60% 80% $0.10 $1.00 $10 $100 Cost per task, log scale Claude Fable 5.1 Gemini 3.8 Flash Claude Sonnet 5.5 GPT-6 Luna 0% 20% 40% 60% 80% $0.10 $1.00 $10 $100 Cost per task, log scale Claude Fable 5.1 Gemini 3.8 Flash

Source: Official SWE-Together leaderboard

ModelEffortHarnessScoreCost per taskOutput tokens
Claude Fable 5.1 opencode 69.3% $8.19 57,800
Claude Fable 5 opencode 68.8% $18 67,700
Claude Opus 5.5 opencode 68.8% $5.23 74,300
Grok 4.7 opencode 65.1% $13 76,300
Gemini 3.8 Flash opencode 64.2% $4.22 92,300
Kimi K3 opencode 63.8% $5.79 40,100
Claude Opus 5 opencode 63.8% $14 92,700
Claude Opus 4.6 opencode 62.4% $8.34 44,500
Muse Spark 1.3 opencode 62.4% $3.19 102,300
Claude Sonnet 5.5 opencode 62.4% $1.95 45,400
Claude Opus 4.7 opencode 61.5% $12 74,300
Claude Opus 4.8 opencode 61.5% $9.28 71,800
Grok 4.6 opencode 60.6% $6.24 37,700
GPT-6 Astra opencode 60.6% $11 31,500
GPT-6 Sol opencode 60.6% $3.36 31,100
GPT-6 Luna opencode 59.6% $0.25 59,900
GPT-6.1 Sol opencode 58.3% $2.13 36,800
GPT-5.5 opencode 58% 29,900
GPT-5.6 Sol opencode 57.8% $5.09 27,800
GLM-5.2 opencode 55% 41,700
GLM-5.1 opencode 52% 41,600
DeepSeek-V4-Pro opencode 48% 49,800

3 models have held number one on the official leaderboard since its release in June 2026

Lab claims count from the day the card came out, independent runs from the model’s release.

Anthropic
Own leaderboard 3 leaders

Source: Official SWE-Together leaderboard

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

On the benchmark’s own leaderboard Best so far
0% 20% 40% 60% 80% 100% 2026 Near the ceiling (85%) Claude Fable 5.1 Claude Fable 5 Claude Opus 4.6 0% 20% 40% 60% 80% 100% 2026 Near the ceiling (85%) Claude Fable 5.1 Claude Opus 4.6

Source: Official SWE-Together leaderboard

No lab model card reports it yet

We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.

More in Coding

All 282 in Coding
  • SWE-bench Verified In use 500 human-validated GitHub issues from 12 Python repos. Agent writes a patch that must pass hidden tests. Claude Opus 4.7 83.5%
  • LiveCodeBench v6 In use Competitive programming problems collected after model cutoffs from LeetCode, AtCoder, Codeforces. Scored pass@1 on hidden tests. DeepSeek-V4-Pro 93.5%
  • SWE-bench Multilingual In use 300 GitHub-issue tasks across nine programming languages in SWE-bench format. Patch graded by repository tests. Claude Fable 5.2 96.6%
  • DeepSWE In use 113 original long-horizon engineering tasks across 91 repos and five languages, written from scratch. Hand-written verifiers accept alternative solutions. GPT-6 Astra 74.1%
  • SciCode In use Scientist-curated research coding problems split into subproblems across natural sciences. Code checked against test cases. Seed2.1 Pro 59.8%
  • Codeforces rating In use Model solves recent Codeforces contest problems. An Elo-style rating is computed from simulated contest performance. DeepSeek V4.1 Flash 3,471