Can decision AI serve as the router and guard of an agent?
AIB DecisionBench-Agent measures the working roles decision AI takes on inside AI agents. It measures how well a model serves as the router, which decides whether to call a tool, and the guard, which stops harmful requests and answers, and uses hard knowledge questions to show the areas where decision models reach their ceiling.
- 23
- Models
- 3
- Tests
- 2,508
- Items
- 80,691
- Decisions
Design intent
Decision AI does not write text; it picks one of a set of options, with a probability, quickly and cheaply. That is why agents often hand it calls such as where to route a request, whether a tool may be called and whether content is harmful. We check whether it can actually do these jobs, using public tests that researchers already rely on.
How it is measured
Items are drawn from three public datasets with a fixed seed, and every AI model gets the same items in the same format. Items with options are asked a second time in reversed order, to see whether the option position sways the answer. We don't republish the items, but the datasets, versions and seed are listed, so anyone can re-run the measurement under the same conditions.
Metrics
- Overall score — the router score and the guard score, averaged with equal weight, out of 100
- Router (When2Call) — accuracy at choosing whether to call a tool, ask for more information, or say it can't help
- Guard (WildGuardTest) — average F1 score at telling whether a request is harmful, whether a response is harmful, and whether the response refuses
- Hard knowledge (HLE multiple choice) — accuracy on very hard knowledge questions, shown separately and kept out of the score
- Response time and cost — kept out of the score, shown in their own columns
In the October 17 – 24, 2026 run, the top overall score among 23 decision AIs went to D1 Ultra (92.8).
- Best router: D1 Ultra — router score 89.8
- Best guard: Drex Max — guard score 96.7
- Decider 1 most often answered right away when it should have used a tool or asked for information (always wrong, 24.6%)
Overall ranking
- Router role
- 89.8
- Guard role
- 95.9
- Hard knowledge
- 16.1
- Time · 1,000
- 10m 10s
- Cost · 1,000
- $0.024
- Router role
- 89.2
- Guard role
- 95.2
- Hard knowledge
- 15.4
- Time · 1,000
- 10m 15s
- Cost · 1,000
- $0.013
- Router role
- 89.2
- Guard role
- 95.1
- Hard knowledge
- 15.4
- Time · 1,000
- 10m 28s
- Cost · 1,000
- $0.013
- Router role
- 86.2
- Guard role
- 94.2
- Hard knowledge
- 12.8
- Time · 1,000
- 14m 52s
- Cost · 1,000
- $0.011
- Router role
- 85.4
- Guard role
- 94.6
- Hard knowledge
- 19.5
- Time · 1,000
- 7m 12s
- Cost · 1,000
- $0.039
- Router role
- 83.0
- Guard role
- 96.7
- Hard knowledge
- 19.3
- Time · 1,000
- 9m 23s
- Cost · 1,000
- $0.039
- Router role
- 83.6
- Guard role
- 94.7
- Hard knowledge
- 20.9
- Time · 1,000
- 7m 2s
- Cost · 1,000
- $0.039
- Router role
- 84.0
- Guard role
- 93.2
- Hard knowledge
- 9.6
- Time · 1,000
- 7m 46s
- Cost · 1,000
- $0.0065
- Router role
- 84.4
- Guard role
- 91.6
- Hard knowledge
- 12.2
- Time · 1,000
- 11m 13s
- Cost · 1,000
- $0.023
- Router role
- 84.4
- Guard role
- 90.5
- Hard knowledge
- 14.0
- Time · 1,000
- 10m 48s
- Cost · 1,000
- $0.035
- Router role
- 86.4
- Guard role
- 87.6
- Hard knowledge
- 11.6
- Time · 1,000
- 12m 23s
- Cost · 1,000
- $0.023
- Router role
- 87.8
- Guard role
- 84.9
- Hard knowledge
- 11.4
- Time · 1,000
- 16m 20s
- Cost · 1,000
- $0.0058
- Router role
- 79.0
- Guard role
- 92.9
- Hard knowledge
- 11.4
- Time · 1,000
- 10m 12s
- Cost · 1,000
- Free for now
- Router role
- 76.0
- Guard role
- 94.9
- Hard knowledge
- 12.8
- Time · 1,000
- 8m 22s
- Cost · 1,000
- $0.166
- Router role
- 76.6
- Guard role
- 90.4
- Hard knowledge
- 12.8
- Time · 1,000
- 4m 24s
- Cost · 1,000
- $0.065
- Router role
- 74.2
- Guard role
- 87.0
- Hard knowledge
- 14.6
- Time · 1,000
- 1h 20m
- Cost · 1,000
- $0.044
- Router role
- 73.0
- Guard role
- 87.7
- Hard knowledge
- 9.8
- Time · 1,000
- 5m 49s
- Cost · 1,000
- $0.103
- Router role
- 68.2
- Guard role
- 74.8
- Hard knowledge
- 9.8
- Time · 1,000
- 13m 54s
- Cost · 1,000
- $0.024
- Router role
- 61.2
- Guard role
- 81.6
- Hard knowledge
- 14.0
- Time · 1,000
- 8m 37s
- Cost · 1,000
- $0.044
- Router role
- 75.4
- Guard role
- 66.5
- Hard knowledge
- 11.0
- Time · 1,000
- 7m 5s
- Cost · 1,000
- $0.061
- Router role
- 46.6
- Guard role
- 87.3
- Hard knowledge
- 12.4
- Time · 1,000
- 13m 51s
- Cost · 1,000
- $0.037
- Router role
- 30.2
- Guard role
- 65.2
- Hard knowledge
- —
- Time · 1,000
- 11m 8s
- Cost · 1,000
- $0.029
- Router role
- 40.4
- Guard role
- 18.8
- Hard knowledge
- 11.6
- Time · 1,000
- 7m 9s
- Cost · 1,000
- Free for now
The overall score averages the router (When2Call accuracy) and the guard (WildGuardTest F1) with equal weight. Hard knowledge (HLE multiple-choice accuracy), time and cost are shown for reference and do not count toward the score. ± is a 95% interval from resampling the items, and items the provider refused to judge count as wrong.
Reliability
Each dot = a confidence range · size = number of answers in it
Datasets
Router role — When2Call evaluation details
Given a user message and the list of available tools, the model picks the right one of four replies: call a tool, ask for more information, say it can't help, or answer straight away. The correct reply is always one of the first three; answering straight away makes something up without the tool, so it is always wrong.
When2Call
EnglishGuard role — WildGuardTest evaluation details
The model reads a user request and an AI response and answers three yes/no questions: is the request harmful, is the response harmful, and does the response refuse the request.
Only a small share of rows have a harmful response, so answering "no" every time still scores high on accuracy. So instead of accuracy, the guard is scored with an F1 score that counts both misses and false flags, as in the original paper.
WildGuardTest — harmful request
EnglishWildGuardTest — harmful response
EnglishWildGuardTest — refusal
EnglishHard knowledge — HLE evaluation details
The router and guard are jobs decision AI actually does inside agents, so they make up the overall score. The hard knowledge test is the opposite: a reference for whether judgments that need expert knowledge can be left to decision AI or should go to a general LLM. It uses the text-only multiple-choice questions from Humanity's Last Exam, hard knowledge questions written by experts; with 5–26 options each, random guessing gets 16.5% on average. Because it measures a different ability from the roles, it is shown separately from the overall score.
Choosing at random would be right 16.5% of the time. Of the 23 models that finished, 3 scored higher than that.
Not measurable: the model's limit on options or input length kept it from taking more than 2% of this test's items. Counting only the items it could take would leave the ones with fewer options or shorter text and inflate the score, so this column is left empty. At 2% or less, only the items it couldn't take are left out.
Humanity's Last Exam — multiple choice (text only)
EnglishMethodology
How one item is scored
- 1
Same items
Items drawn from the datasets with a fixed seed are sent to every AI model in the same format. Very long items (over 8,000 characters) were left out beforehand.
- 2
A probability per option
The model returns a probability for each option, and the most likely option is scored as its answer. For yes/no items, a "yes" probability of 0.5 or more counts as "yes".
- 3
Asked again in reverse
Items with options are asked once more in reversed order. Scores come from the original-order answers; the reversed answers only measure how often the option position changed the answer.
- 4
Grouped by role
The router is scored by accuracy, the guard by the average F1 score of its three questions, and hard knowledge by accuracy. The overall score averages the router and the guard with equal weight.
What the model receives
Every metric by modelSamples, probability quality, accuracy by form and language, latency, cost
Sample sizes, probability quality, results by question form and language, latency distribution and cost. Models still in progress are computed from the answers received so far.
Test dataRole, item count, license and source revision per dataset
ReproducibilitySampling seed and item fingerprints
Items were drawn with a fixed seed (20261003); the dataset version (commit) and an item fingerprint are recorded to confirm the items are the same. Item text is not republished, following the datasets' terms of use.
Router — When2CallAn illustrative example in the same shape (not a real item)
The state holds the list of available tools and the user message; the options are the four reply texts, shuffled for each item.
Guard — WildGuardTestAn illustrative example in the same shape (not a real item)
The state holds the request (and the response), and one yes/no question is asked. Each row is sent three times, once per question (harmful request, harmful response, refusal).
Hard knowledge — HLE multiple choiceAn illustrative example in the same shape (not a real item)
The question text goes in the state and the options keep their "A. …" form. Some options refer to others by letter ("both A and B"), so the letters are kept.
Good to knowScoring rules and measurement conditions
- When a provider refuses to judge an item because of its content, it counts as wrong; in the guard score it counts as the opposite of the correct answer.
- Errors and timeouts are asked again to fill them in and are left out of scoring. Models below 100% coverage are marked as still measuring.
- Items over 8,000 characters were left out, so that models with short input limits don't fail only on long items.
- Models with free-usage limits fill in their items over several days.
- Some providers' terms let them use the inputs they receive for training, so later runs may involve items the model has seen.
- Items are sent in their original English.
- Perplexity Decider v1 27B returned the same answers as a model under another name at measurement time (every item matched), so it was treated as the same model and left out of the ranking.
FAQ
Q.What does AIB DecisionBench-Agent measure?
A.It uses public tests to measure two working roles decision AI takes on inside AI agents: the router, which decides whether to call a tool, and the guard, which stops harmful requests and responses. Hard knowledge questions show its ceiling separately.
Q.How is it different from DecisionBench-KJ and DecisionBench-Game?
A.KJ checks how accurately models judge Korean and Japanese text, and Game checks whether they decide in time in real-time situations. Agent measures roles inside an agent with public English tests; because the datasets are public, anyone can re-run it under the same conditions.
Q.Which decision AI scored highest?
A.In the October 17 – 24, 2026 run, the top overall score among 23 models went to D1 Ultra (92.8). The best router was D1 Ultra and the best guard was Drex Max.
Q.Why is HLE left out of the overall score?
A.Decision AI scores low on very hard knowledge questions, so mixing them in would hide the differences in routing and guarding. That's why HLE is shown separately as hard knowledge.
Q.Why is the guard scored with an F1 score instead of accuracy?
A.Harmful responses are only a small share, so answering "not harmful" every time still scores high on accuracy. The F1 score checks both that harmful items are caught and that harmless ones aren't wrongly flagged.
Q.Is this the same as the Artificial Analysis Decision Index?
A.No. Some of the public tests overlap (When2Call, WildGuardTest, HLE), but we set the measurement, scoring and score composition ourselves and use no result data from elsewhere. The two scores can't be compared.
Want a decision AI measured?
Tell us which decision AI you'd like added to the Agent benchmark. We'll review it for the next run.
D1 Ultra
Jev 1.14
Microsoft-Decision-1
Clef
Classify-1