T1-Bench - Parameter F1: leaderboard

T1-Bench (2026) tests tool-using assistants in multi-turn customer-service conversations across 11 service domains and 14 multi-domain combinations, with a simulated user following a written policy and three trials per conversation. This board is the F1 score in percent of the parameters of each reference tool call against the matching call the assistant made; higher is better.

Metric: Parameter F1 (%) of each ground-truth tool call against the best-matching generated call of the same tool; T1-Bench: 525 multi-turn customer-service conversations over 25 domain settings (11 single domains and 14 combinations of 2 to 11 domains, 76 tools), a Gemma4-26B-A4B-it user simulator, three trials per conversation at temperature 1.0; averages weighted by conversations per setting; higher is better. Source: arxiv.org. Saturation forecast: Estimated already saturated. 12 models tracked.

Top models

#ModelScoreOverall rank
1Gemma 4 31B (IT)91.06#342
2Claude Opus 4.689.67#102
3Gemma 4 26B A4B (IT)89.58#549
4Claude Haiku 4.589.14#568
5Claude Sonnet 4.589.1#250
6gemma-4-E4B-it88.87#1469
7GPT-OSS-120B (High)88.66#700 (GPT-OSS-120B)
8Gemma 4 E2B (IT)88.35#2303
9GPT-5.4 (Low)83.99#123 (GPT-5.4)
10GPT-5.4 Mini (Low)78.75#389 (GPT-5.4 Mini)
11GPT-OSS-20B (High)68.72#1147 (GPT-OSS-20B)

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=t1-bench-parameter-f1 · How It Works · Data refreshed daily, snapshot 2026-11-13.