definefontfamily [dejavu] [serif] [DejaVu Serif]
definefontfamily [dejavu] [sans]  [DejaVu Sans]
definefontfamily [dejavu] [mono]  [DejaVu Sans Mono]
definefontfamily [dejavu] [math]  [XITS Math] [scale=1.1]

setupbodyfont[dejavu]

starttext
input knuth
stoptext

...
selectfont      > The requested font 'DejaVu Serif' has no files for the 'tf' alternative, Latin Modern is used instead.
selectfont      > The requested font 'DejaVu Sans' has no files for the 'tf' alternative, Latin Modern is used instead.
selectfont      > The requested font 'DejaVu Sans Mono' has no files for the 'tf' alternative, Latin Modern is used instead.
...
mkiv lua stats  > loaded fonts: 2 files: lmroman10-regular.otf, xits-math.otf
mkiv lua stats  > font engine: otf 3.029, afm 1.512, tfm 1.000, 4 instances, load time 1.252 seconds
...

$ luaotfload-tool --find='MuseJazz' -F
luaotfload | resolve : Font "MuseJazz" found!
luaotfload | resolve : Resolved file name "/usr/share/fonts/mscore/MuseJazz.ttf"

luaotfload-tool --update

export OSFONTDIR="/usr/share/fonts;$HOME/.local/share/fonts;/usr/local/share/fonts;$HOME/.fonts"
context test

context --generate

mtxrun --generate

$ mtxrun --script fonts generate
mtxrun          | unknown script 'fonts.lua' or 'mtx-fonts.lua'
$ mtxrun --script fonts --list --all --pattern='*'
mtxrun          | unknown script 'fonts.lua' or 'mtx-fonts.lua'

$ luatools --generate
mtxrun          | unknown script 'base.lua' or 'mtx-base.lua'

$ kpsewhich texmf.cnf
/usr/share/texlive/texmf-dist/web2c/texmf.cnf

$ mtxrun --script fonts --list --all --pattern='*' | egrep -i muse
0

$ mtxrun --script fonts generate
mtxrun          | unknown script 'fonts.lua' or 'mtx-fonts.lua'