Test / Benchmark Apollo‑1 Best LLM Agent Δ
τ‑Bench‑Airline 90.8–92.5 % Claude‑4   60 % +51%
Google Flights** – 111 live booking chats 83 % Gemini 2.5‑Flash  22 % +277%
Amazon Retail** – 120 live shopping chats 90.8 % Rufus  16.7 % +444%

I. Generative AI Hits a Wall on τ‑Bench; Apollo‑1 Breaks Through

90.8 – 92.5 % Pass^¹ and a 30-point lead show that, while Generative AI serves individual users well, Neuro-Symbolic AI is required for conversational agents that operate on behalf of companies and other entities.

New State‑of‑the‑Art on τ‑Bench-Airline

τ-Bench-Airline is the toughest public benchmark for tool-using conversational agents, measuring complex, multi-turn user-agent interactions and advanced tool use. On the headline Pass^¹ metric, preliminary results place Apollo-1 in the 90.8–92.5 % range—over 30 percentage points ahead of Claude-4’s 60 %.

tau-bar-chart-1.svg

Model Pass^1 Δ vs Apollo‑1
Apollo‑1 (Neuro‑symbolic) 90–92.5 %
Claude 4 Sonnet (LLM) 60 % −30 pt
Claude 4 Opus (LLM) 59.6 % −31 pt
OpenAI O3 (LLM) 54.2 % −36 pt

Final Pass^¹, Pass^², Pass^³, and Pass^⁴ numbers will be published in our official τ-Bench report in December 2025.

Example Scenario

Task #12: Reservation Update & Booking.

Time Speaker Message
12:18 PM Agent Welcome! This is a simulation environment for the TAU Benchmark – Airlines. How can I help you today?
12:18 PM User Hi, I want to book the same flights as my current reservation, but this time for my friend Ivan Smith. His date of birth should be in my profile.
12:18 PM Agent Thank you for your request! To get started with booking the same flights for Ivan Smith, could you please provide your user ID?
12:19 PM User My user ID is ivan_muller_7015.
12:19 PM Agent Agent Options:
HAT097, HAT251
07:00 DTW PHX 1 stop 15:00 SEA
"Shortest total duration, minimal layover, two segments only"
$186 Basic Economy
$375 Economy
$745 Business
HAT275, HAT156
00:00 DTW PHX 1 stop 10:00 SEA
"Early arrival, short layover, two segments, good price"
$116 Basic Economy
$313 Economy
$725 Business
HAT169, HAT069
04:00 DTW JFK 1 stop 12:00 SEA
"Two segments, but first layover is very short"
$123 Basic Economy
$273 Economy
$677 Business
HAT275, HAT251
00:00 DTW PHX 1 stop 15:00 SEA
"Early start, longer layover in PHX, two segments"
$150 Basic Economy
$342 Economy
$826 Business
HAT035, HAT045
15:00 DTW PHX 1 stop 02:00 SEA
"Long layover in PHX, two segments, low price"
$121 Basic Economy
$315 Economy
$720 Business
HAT097, HAT045
07:00 DTW PHX 1 stop 02:00 SEA
"Long layover in PHX, two segments, no basic economy"
$152 Basic Economy
$312 Economy
$849 Business
12:19 PM Agent I found the same one-stop flights as your current reservation—HAT097 (DTW to PHX, departs 7:00am) and HAT251 (PHX to SEA, departs 12:00pm) in economy class, total fare $375. Please confirm if you’d like to proceed with booking these flights for Ivan Smith.
12:19 PM User Yes, please proceed. I’d like to use my certificate for payment—can you tell me how much of my certificate balance will remain after this booking?
12:19 PM Agent Thanks for confirming. The total fare for Ivan Smith’s flight is $375, which will be deducted from your $500 certificate—leaving a $125 balance that will be forfeited, as unused certificate funds are non-refundable. Would you like to add travel insurance for $30 (covers full refund for health or weather-related cancellations), and should I go ahead with the booking?
12:19 PM User If $125 will be lost, I’d rather use my gift card and credit card instead. Can you switch the payment to those?
12:19 PM Agent Thanks for the update. To confirm, you’d like to book flights HAT097 (DTW to PHX, departs 7:00am) and HAT251 (PHX to SEA, departs 12:00pm) on 05-17-2024 in economy for Ivan Smith, using your gift card and credit card for the $375 fare. Would you like to add travel insurance for $30 (covers full refund for health or weather-related cancellations)?
12:19 PM User No insurance, and I don’t need any bags. Please go ahead and book it.
12:19 PM Agent Ivan Smith is now booked on flights HAT097 and HAT251 in economy on 05-17-2024, with no checked bags or insurance. Payment was completed using your gift card ($128) and credit card ($247), and your reservation ID is HATHAU. Let me know if you need the itinerary details or have any other requests.

Why Purely Generative Agents Hit a Reliability Wall