Contextual Boundaries for AI Agents
Northeastern University

METR and Redwood Research, August 2026

TechCrunch, March 18, 2026, reporting The Information
Rule-based boundaries are stated clearly by rules and enforced by mechanisms like a sandbox.
Inside the boundary are the actions the agent can technically take, limited by its capabilities.
Drawing the contextual boundary takes contextual understanding, so the judgement has to come from a model.
The former can be enforced at the infrastructure level. The latter needs to be part of the model’s capabilities, so that its capabilities are not compromised, and it does not comply superficially or seek circumvention.
NeurIPS 2024, Datasets and Benchmarks Track
Yijia Shao
Tianshi Li
Weiyan Shi
Yanchen Liu
Diyi YangThis seed describes a flow that should not happen: John's job search reaching his manager by email.


In a nutshell
Privacy is appropriate information flow.
In contrast to: privacy = personally identifiable information (PII)
The same norm is tested at three levels of context: probing questions work at every level, and the agent’s final action is evaluated at the trajectory level.
From the trajectory, extract the sensitive information items \(i_1, \ldots, i_m\). The final action \(a_T\) leaks if, for some \(t\), \(i_t\) can be inferred from \(a_T\), even when it is not stated word for word.
\[\mathrm{LR} = \frac{1}{|D|} \sum_{(S,V,T) \in D} \mathbb{1}\big[\exists\, t : f(i_t, a_T) = 1\big]\]
Here \(D\) is the dataset and \(f\) is the leakage judge. \(\mathrm{LR}_h\) computes the same rate over the actions judged helpful, so that a model cannot score well by failing the task.
Each seed is expanded into a vignette and then into an agent trajectory, and unit tests with the Surgery Kit check each step.
Stronger models stay accurate at every level, while Llama-3-8B falls from 88.8% at the seed level to 31.4% at the trajectory level.
GPT-4 and Claude-3-Sonnet answer almost every trajectory-level probing question correctly, yet leak information in 26.4% and 38.3% of their actions.
Adding privacy-enhancing content to the system prompt lowers leakage for some models and raises it for others.

A helpful action can leak the sensitive information, while an action that protects it can be judged unhelpful.
Frontier models still leak in 40% to 51% of cases, not far below small open models at 49% to 57%.
Tamber et al., PrivacyAlign, 2026
Meta, Muse Spark safety report (April 2026)

Claude Opus 4.6 and Muse Spark reveal the most stored user information in tasks where it does not belong.
Google DeepMind, Gemini 4 Argon safety report (October 2026)

Gemini 4 Argon behaves safely in 83% of tasks with no attacker, and in 27% after 15 attack attempts.
Preprint, 2026
Zhiping Zhang
Franklin Mingzhe Li
Zihao Huang
Tianshi LiAgency is the fiduciary relationship that arises when one person (a “principal”) manifests assent to another person (an “agent”) that the agent shall act on the principal’s behalf and subject to the principal’s control, and the agent manifests assent or otherwise consents so to act.
American Law Institute, Restatement (Third) of Agency, § 1.01 (2006)
Under U.S. agency law, the boundary of delegation is defined primarily by the scope of authority the principal grants to the agent.
“Buy a laptop for me, with a maximum budget of $1,500.”
Current agent safety benchmarks look at actions with safety harm. AuthorizationBench looks at acting out of authorization, with or without harm.
A trajectory \(T\) completes the task if it satisfies at least one \(c \in C\). It is out of authorization if it performs at least one \(o \in O\). The two are judged independently.
\[\mathrm{OAR} = \frac{1}{|D|} \sum_{(O, T) \in D} \mathbb{1}\Big[\bigvee_{t=1}^{|O|} g\big(o_t, T, E(T)\big)\Big]\]
Here \(D\) is the set of tasks and trajectories, \(g\) is a post-hoc judge, and \(E(T)\) is state-based evidence from the sandbox. The judgment asks whether the action occurred, not whether it caused harm.
Each real incident becomes a contract and a sandboxed task, and contextual expansion grows 44 original tasks into 286.
Once the original tasks are validated, we systematically produce new versions by modifying one contextual dimension.

No configuration is free of out-of-authorization behavior, and the overall rate is 19.2%.

Most configurations complete nearly every task, and completion does not predict how often an agent oversteps (r = −0.00).

Raising reasoning effort lowers overstepping for some configurations and raises it for others.
Across 91 controlled pairs, agents overstep about as often without direct harm as with it.
Across 87 controlled pairs, benign pressure causes more overstepping than malicious injection.
| PrivacyLens | AuthorizationBench | |
|---|---|---|
| The question | What may I share? (information control) | What may I do? (action under delegation) |
| Human norm system | Contextual integrity: flows follow the norms of the context | Agency law: actions stay within the scope of authority the principal granted |
| What sets the boundary | The relationship between sender, recipient, and subject | The relationship between principal and agent, and the task |
Zhiping ZhangNortheastern
Yijia ShaoStanford
Weiyan ShiNortheastern
Yanchen LiuMIT
Diyi YangStanford
Franklin Mingzhe LiUNC Chapel Hill
Zihao HuangNortheastern
Tianshi LiNortheasternZhiping is looking for an internship!