Give us something that measures a combination of efficiency and intelligence.
I think this would allow for some interesting tactics for smaller models - eg they could do things like computer use to test their results and grind on problems for longer to verify the outputs, whereas larger models may not have budget to self-test.
In fact, one thing that still bothers me after months is the gpt-5.5 official submission. This task in particular https://www.tbench.ai/leaderboard/terminal-bench/2.0/codex/0...
The task has the following timeouts (https://github.com/harbor-framework/terminal-bench-2/blob/ma...).
[verifier]
timeout_sec = 1200.0
[agent]
timeout_sec = 1200.0
[environment]
build_timeout_sec = 600.0
Which means no agent should take more than 3000 seconds doing it. Two out of five attempts in the link above took well over 3000 seconds (75min and 80 min respectively). Even though they failed, the fact that they ran that long is sus.
Goodhart’s Law at work
On the one hand, kudos to them for actually doing that work.
On the other hand, garbage in, garbage out. It’s a bit embarrassing for the original authors to have not actually checked, and it’s embarrassing for everyone downstream to have not checked either.
Also if you check the article, although an LLM did find issues, it tended to underestimate issues that professional software engineers found.
For context, I've been iterating on a "supervisor" to replace a lot of the rigamarole spent when working with Codex/Claude Code, and recently ran this agent against Terminal Bench 2.1
At first I was excited, because my spec-driven supervisor outperformed vanilla codex on a bunch of tasks, however as I looked deeper, I found a ton of issues with the tasks themselves.
The main takeaway is that the instructions are often ambiguous while the test cases are overly specific.
A few examples:
- For `configure-git-webserver` the task includes language like "so that I can run" which blurs the line between what the agent should deliver vs. what should be removed. This causes an overthinking agent to configure the server, and then remove the exact files that the verifier checks, because if the user were to run the same commands, they would conflict.
- For `make-mips-interpreter` the task includes the language "I will check that you booted doom correctly" which causes the agent to retain the generated file `/tmp/frame.bmp` because the supervisor expects the user to check that _it_ booted Doom correctly, not that Doom boots correctly in an isolated way. The verifier then fails to start Doom, because it exits when an existing `/tmp/frame.bmp` exists, not checking to see that it's created from the boot[0].
- For `mcmc-sampling-stan` the supervisor agent often reached the right value, but produced a domain-specific numeric output in scientific notation, rather than a simple decimal form. The verifier fails because it parses the result incorrectly[1].
These are just a few of the inconsistencies I've found, which leads me to believe that Terminal Bench 2.1 is already saturated, and the results from GPT-5.6 and Mythos are basically at the top of the expected threshold (88.8% and 88% respectively).
The biggest issue, as I can tell, is that most benchmarks are "one-shot" and rarely test the model+harness on long iteration tasks, which is the primary way most users use these tools in practice.
[0] https://github.com/harbor-framework/terminal-bench-2-1/issue...
[1] https://github.com/harbor-framework/terminal-bench-2-1/issue...
Overly strict tests enforce specific implementation details not specified in the prompt, invalidating many functionally correct submissions.
Underspecified prompts omit requirements that hidden tests enforce and that are not reasonably inferable.
Low-coverage tests under check the requested feature, so incomplete fixes can pass.
A misleading prompt points models toward the wrong behavior or contradicts what tests require.
If the goal is, "how does my model compare to real SWEs", these are pretty reasonable situations that your model will have to encounter. It's a little like making a nursing exam and then flagging that some of the tests required you to ask the attending doctor for additional information that's not in the chart, or that the patient's family didn't fully explain their aging grandma's medical history.
I can understand why they might want a tighter benchmark, but if you're OpenAI and you promised your model as a replacement for real workers, this isn't the best look. It seems like you would want to test these things.
In my own testing, no frontier model knows how to replicate an original 1990s Super Soaker prototype design, which for the most part, should be almost completely possible with Home Depot parts.
They just don't understand PVC parts, triggers, etc.
This all feels like a 2024 re-run. Oh, ChatGPT is going to cure cancer? Then find ONE rare cancer and CURE IT. OpenAI has access to the best models and compute - so cure fucking cancer! What the fuck are you waiting for?