human-gate

flowchart TD
    Task([Task input]) --> Pipeline[Autonomous pipeline]
    Pipeline --> Present[Present output to human]
    Present --> Gate{Human approves?}
    Gate -- yes --> Action[Execute irreversible action\ne.g. merge / deploy]
    Action --> Done([Done])
    Gate -- no --> Halt([Halt — no action taken])
    Gate -- timeout/no answer --> Halt

A human approval step is placed at the boundary between autonomous execution and irreversible action. The system stops and waits — it does not proceed on timeout.

How it works

The autonomous pipeline runs to completion and produces a candidate output.
The candidate is presented to a human for review.
The human explicitly approves (yes) or rejects (no).
Only on explicit approval does the system execute the irreversible action (merge, deploy, send, etc.).
On rejection — or if no answer is given — the pipeline halts. Nothing is committed.
If the pipeline’s own model call is refused by a safety classifier, it ends at the gate the same way: halted, reported, no action.

Where it came from

ai-dev-tools chose the human as a gate, not a relay: the developer approves at the points that need context or business judgement, and nothing is merged without them. → ADR-001
autonomous-dev-loop automates everything up to the merge and never merges: no merge call exists anywhere in its scripts or workflows.

When to use

Any pipeline whose final action is irreversible: merges, deploys, emails, billing charges.
Pipelines where autonomous quality is high but accountability must remain with a human.

When not to use

High-volume, low-risk tasks where human review is a bottleneck and the cost of a mistake is low.
Fully automated CI pipelines where human latency is unacceptable and rollback is cheap.

Trade-offs


Pro	Hard guarantee that no irreversible action occurs without human sign-off
Pro	Simple to reason about — the gate is a single, explicit point
Con	Introduces human latency into the pipeline
Con	Can be bypassed if the “irreversible” action is not correctly identified

Failure modes

Gate bypass — the irreversible action is split across two steps; the second step is not guarded.
Rubber-stamping — humans approve without reading, defeating the purpose of the gate.
Timeout auto-proceed — a poorly implemented gate proceeds on timeout; this implementation explicitly does not.