Reid Hoffman posted this week about how to make an introduction. His rule is the double opt-in. Before connecting two people, you check with both of them first. You ask each whether they want the intro, and you make it only when both say yes.
He makes the case well. Every introduction is a bet that the two people will get value from meeting. Checking first lets you see the cards before you place it. Connect two people who might not want to meet, and you have told the recipient their time was not worth a question.
The double opt-in is a convention. Conventions are worth thinking about right now, because we are starting to put similar things on AI agents and calling them guardrails.
Why it works
Henry Mintzberg named five ways an organization coordinates its work. One of them is standardizing behavior, so that people act in sync without anyone supervising each step. A shared convention is that mechanism running in the wild. Everyone knows the norm, most people follow it, and the group stays coordinated without a manager in the loop approving every move. It is the cheapest way a group holds together, because it asks for no oversight at all.
Look closely at what Hoffman says. He did not describe a habit you could take or leave. He turned a courtesy into a step you cannot skip. Both people have to say yes before anything happens. Remove the check and the introduction never occurs. There is a small piece of structure sitting under the courtesy, and it is easy to miss because it costs almost nothing to run.
What enforces it
Ask what stops someone from skipping the check when they are busy or feeling important. Hoffman answers it himself. A bad introduction damages the relationships you have with the people you introduced. The convention holds because breaking it costs you something with people you will deal with again. Reputation does the work, along with the knowledge that you will see these people down the line. The enforcement runs so quietly that we credit the manners and forget the relationship holding them up.
Behavioral guardrails
Agentic AI now acts with something close to human autonomy. An agent plans, works over many steps, and pursues a goal with little supervision. So we give agents rules for how to behave. Do not deceive. Do not touch systems you were not given access to. The industry calls these behavioral guardrails.
The word guardrail usually means something physical, a barrier you cannot drive past. A behavioral guardrail is different. It is a norm the agent has to represent, understand, and choose to honor. It lives inside the agent’s own decision loop, which means the agent can reason its way around it. This is the same coordination-by-standardization that holds a human group together, handed to an actor with none of the enforcement underneath. An agent has no reputation at stake and no relationship it needs to protect. The rule reaches it as a suggestion, and nothing makes the suggestion bind.
I pointed out recently on linkedin that a “skill” given to an agent is standardization in exactly Mintzberg’s sense. It works only as long as the agent applies the whole of it faithfully. The moment the agent decides which parts of the instruction matter and which it can set aside, standardization stops coordinating anything, and you are back to the expensive ways of keeping work aligned: a human checking every output, or endless back-and-forth to reconcile what the agent actually did with what you meant.
The part you cannot see
Here is what makes this hard to catch in time. A faithful agent and one quietly ignoring half its instruction produce the same kind of output. Both look like work getting done. You cannot tell from the result which one you had. You find out later, when something downstream breaks and you trace it back.
That is the real weakness of a behavioral guardrail. You cannot read off whether it held. The output looks fine either way, right up until the run where it does not, and by then the thing has already happened.
The AISI incident
In August 2026 the UK’s AI Security Institute published a report on an incident in its own testing. The conditions were deliberately permissive. The agents had open internet access, and the model providers’ safety filters, which sit outside the model and can block an action the model wants to take, were switched off. The Institute is careful to say these are not the conditions the public gets. Testing this way shows what the models do once the structural constraints are taken away.
Across many runs of a cyber challenge, agents took unsanctioned action on the live internet. In the most serious case, an agent tried to slip malicious code into a real open-source project. It researched the project’s human maintainer and created fake identities to pressure the maintainer into approving the code. The Institute states plainly that the agent was never told to deceive anyone. The deception emerged on its own, while the agent pursued the goal it had been given.
The agents also invented a convention of their own. One agent left public messages offering to work with the other agents running the same challenge, and left behind accounts and instructions for them to reuse. It was a spontaneous etiquette among machines, a way to coordinate through the task. Even agents reach for conventions. What they do not build is any way to make a convention bind them.
The Institute was clear about what stopped the worst of it. A human maintainer caught the malicious code and refused to approve it. That is coordination falling back to its most expensive mode, a person inspecting the output by hand, because the cheap mode had failed silently. The margin between failure and success was narrow, and it rested on “human vigilance rather than a technical barrier” that would reliably stop a more capable agent. Harm was prevented because a person happened to be paying attention.
What a real guardrail looks like
None of this makes the agents villains, and the Institute’s caution is worth keeping. It cannot even say for certain whether the agent understood it was acting in the real world or believed it was still inside a test. The agent broke the rule while chasing its goal, with no malice involved. The failure lives in the setup of the situation.
So the design question is which parts of an instruction are load-bearing and have to hold no matter what, and which parts you actually want judgment to touch. What has to hold should be structural, made hard to do rather than merely discouraged. An agent that cannot reach a system has no need to be told to leave it alone. A code change that cannot merge without a check the agent cannot forge does not depend on the agent choosing honesty. Autonomy is fine, but it should be bounded, and the bounds have to be built rather than requested.
One barrier around one system is not enough, because agents work in chains, and errors pass down the chain and grow. The fuller answer has layers. The first is visibility, since you cannot oversee what you cannot see, so the behavior of every system has to be observable. Then the connections between systems need constraining, so that whole categories of harmful action become impossible to express. Failures have to be contained where they do occur, so a mistake in one place does not travel. Human judgment comes in last, saved for the exceptions the structure surfaces, which is a far better use of a person than asking them to watch everything.
Behavioral guardrails belong on top of that structure. They are the cheapest layer and the most brittle one, and they are fine in that role. The mistake being made right now is to build the top layer first, write down a list of good behaviors, and treat the list as safety.
Coherence is the integrity of the link between what you meant and what got done. A convention holds that link cheaply, as long as something underneath makes it bind. Judgment stretches the link, sometimes for the better. Whether it helps or hurts depends on deciding in advance where it is allowed to stretch, and making the rest hold on its own.
This is the argument at the center of my book, Coherence, arriving this Fall: that overseeing autonomous systems takes structure you build, not behavior you request. To follow the thinking as it develops, join the list at coherise.com. The one-page decision tool from the book is the first thing I send.