The moment
A session set to the fast, cheap configuration is asked a question that turns out to be structural: how the records relate, where the boundary goes. It answers reasonably. The answer is now in the schema, and it will be there in two years.
Why it happens
The dial is set per session, not per task, and the tasks arrive mixed. Nothing marks the moment at which a question stopped being routine, so the configuration that was correct for the last three changes is applied to the one that matters. Cost pressure makes this the default direction of the error.
Why a better model does not fix it
Trivially, a better model here would fix this instance — which is exactly the point: the failure is that nothing chose. The next task will be mis-dialled in whichever direction the previous one left it, and half the time that direction is expensive.
What it costs
Asymmetrically. A rename done at maximum effort wastes a few cents. A boundary chosen by an under-powered session is paid for by every change that crosses it afterwards.
What Majordomus does
A profile is a small file that sets capability class, reasoning effort, verbosity,
presentation, the context to load, the verification required and the checkpoint interval,
independently. A task names one at start, and the generated instructions state which is in
force. deep-work makes a decision record a condition of finishing, so a structural choice
made under it is written down with its reason and its rejected alternative. Where a profile
allows escalation, it is a recorded event after a stated number of blocked attempts.
Before and after
before (cheap, because the last task was cheap) -> the data model
after $ majordomus start "choose the record boundary" --profile deep-work
$ majordomus finish --outcome completed --verify-command "make test"
FAIL profile deep-work requires a decision record for this taskWhat it does not do
Majordomus never selects or invokes a model, and cannot observe what a worker actually ran. Profiles are projected into the instructions and validated as configuration; every profile-related claim is marked advisory for that reason.