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Banks have a rule older than computers: the person who proposes a change cannot be the person who approves it. One clerk enters the payment; a second checks and releases it. It is called maker checker, or the four-eyes principle, and it works not because people are dishonest but because people make mistakes, and a second look catches most of them. Parmana builds maker checker into every change to what agents may do: a policy, an agent’s grant, an external connector, a business signal source, an approver key. Each must be proposed by one identity and approved by a different one. Many teams adopting agents are small. Sometimes one person holds both roles. Is it theater then? No, but it is worth being precise about what it gives.

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How it works

  • The maker proposes. Proposing does nothing on its own; the change waits as pending.
  • The checker approves, with two things: their API key, and a step up authorization signed with a separate private key on their own machine. It covers that one change and is valid for 120 seconds.
  • Self-approval is refused. If the identity that proposed a change tries to approve it, the answer is SAME_ACTOR_CANNOT_APPROVE_OWN_CHANGE. There is no override.
  • Agents cannot take part. Non-human keys are refused on governance routes, and the attempt is logged.
The repository’s approval script also prints the full change and asks the checker to type APPROVE before it signs. Anything else stops it.

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What it gives when one person holds both roles

  1. An agent can never change its own limits. This does not depend on headcount. The most important separation is between agents and the rules agents run under, and no agent key can propose or approve those changes.
  2. One leaked key is not enough. Changing a policy takes the maker’s key, the checker’s key and the checker’s step up private key, which never leaves the checker’s machine. A single API key leaked in a log cannot rewrite the rules.
  3. A forced pause. Proposing and approving are separate steps with different keys. Propose, step away, then review the change as if someone else wrote it. That is the original point of maker checker.
  4. It is ready for the second person. When someone joins, they take the checker role on their own machine with their own step up key. Nothing in the system changes; the control was already enforced.
  5. It holds when you are rushing. During a credential recovery, changes proposed with the wrong key could not be approved with that same key. Annoying, and exactly right. The fix was to give both identities step up keys, so each can approve the other’s change and never its own.

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What it does not give

  • It is not two-person control. One person holding both identities can still approve their own idea in two steps. The control stops accidents and outsiders, not that person.
  • It depends on keeping the keys apart. If both identities’ keys sit together on one laptop, one compromise gets both. Separate storage helps; separate people help more.
  • It does not judge the change. The checker approves what is in front of them. A bad change reviewed by a tired checker is still bad, now with a signature on it. The signature tells you who approved, not whether they were right.
  • Approval records can still be changed by an operator with database service access. Today such changes are detected, not prevented; write-once storage or an external anchor is considered, not built.

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A sound setup for a small team

  • Two identities, even if one person holds both, and never an agent among them.
  • Step up keys for both identities, stored and backed up separately.
  • The habit: propose, step away, review as a stranger.
  • A written plan to add a real second person, on their own device, as soon as possible.
  • Every approval recorded with who proposed, who approved and when, so the history is there for the second person.
Maker checker was never about distrust. It makes important changes slow, visible and attributable. One person can start doing that, as long as everyone is honest that the one person is the weak spot. Read more: Credentials: maker, checker and approver, Human approval.