Benchmark Almanac

tau-bench Retail

Claude 3.5 Sonnet (October 2024) 69.2% leads since October 2024
Dropped

Agents help simulated retail customers through tools while following store policies on the original tasks. The score is pass^1 as a percentage.

One track of tau-bench. The tau-bench record keeps lab scores that combine tracks. Authors mark these original tasks as outdated and point to later benchmarks with revised tasks.

Made by
Sierra
Released
June 2024
Kind
Customer service
Level
Everyday
Scored
Checked automatically
Answers
Agent task
Tasks
All public
Strongest model tested
gpt-oss-120b #125 on the capability index
Last in a launch post
August 2025, dropped before it saturated
Last model added
August 2025
Scores refreshed
November 12th, 2026

In the authors’ words

Existing benchmarks do not test language agents on their interaction with human users or ability to follow domain-specific rules, both of which are vital for deploying them in real world applications. We propose τ-bench, a benchmark emulating dynamic conversations between a user (simulated by language models) and a language agent provided with domain-specific API tools and policy guidelines. We employ an efficient and faithful evaluation process that compares the database state at the end of a conversation with the annotated goal state. We also propose a new metric (pass^k) to evaluate the reliability of agent behavior over multiple trials. Our experiments show that even state-of-the-art function calling agents (like gpt-4o) succeed on <50% of the tasks, and are quite inconsistent (pass^8 <25% in retail). Our findings point to the need for methods that can improve the ability of agents to act consistently and follow rules reliably.

Abstract of τ-bench: A Benchmark for Tool-Agent-User Interaction in Real-World Domains (arXiv:2406.12045, CC0)
2
Models scored in lab cards
2
Launch posts list it, from 1 lab

gpt-oss-120b leads with 67.8%

Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.

Claude 3.5 Sonnet (October 2024) leads with 69.2% across all independent runs

Best score per model across the official leaderboard, Epoch AI’s own runs and any board Epoch AI copied. Each bar and row names its source.

Claude 3.5 Sonnet (October 2024) leads with 69.2%, claims included

Best score per model from every source, including labs’ own numbers and claims Epoch AI collected from reports and papers. Labs pick their own settings, so a claim can beat an independent run of the same model.

  1. 1 gpt-oss-120b 67.8%
  2. 2 gpt-oss-20b 54.8%

Source: Labs’ model cards

Source: Official tau-bench Retail leaderboard

#ModelScoreSettingDateSource
1 gpt-oss-120b 67.8% Aug 2025 Lab model card
2 gpt-oss-20b 54.8% Aug 2025 Lab model card
#ModelScoreSettingDateSource
1 Claude 3.5 Sonnet (October 2024) 69.2% tool-calling Oct 2024 Official leaderboard
2 Claude 3.5 Sonnet 62.6% tool-calling Jun 2024 Official leaderboard
#ModelScoreSettingDateSource
1 Claude 3.5 Sonnet (October 2024) 69.2% tool-calling Oct 2024 Official leaderboard
2 gpt-oss-120b 67.8% Aug 2025 Lab model card
3 Claude 3.5 Sonnet 62.6% tool-calling Jun 2024 Official leaderboard
4 gpt-oss-20b 54.8% Aug 2025 Lab model card

The benchmark's own leaderboard has 3 entries, 2 of them models we track. Switch the scores above to rank them together.

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 Reported by the lab in its model card Best so far
0% 20% 40% 60% 80% 100% 2024 2025 Near the ceiling (85%) Claude 3.5 Sonnet (October 2024) Claude 3.5 Sonnet 0% 20% 40% 60% 80% 100% 2024 2025 Near the ceiling (85%) Claude 3.5 Sonnet (October 2024) Claude 3.5 Sonnet

Sources: Official tau-bench Retail leaderboard and labs’ model cards

No launch post has listed it since August 2025

Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.

OpenAI
DateLaunch postScoreAs the post writes it
Aug 5, 2025 gpt-oss-20b 54.8 Tau-Bench Retail (function calling)
Aug 5, 2025 gpt-oss-120b 67.8 Tau-Bench Retail Function calling

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