  The Einstein Probe (EP) achieved its first detection and localization of a
bright X-ray flare, EP240219a, on February 19, 2024, during its commissioning
phase. Subsequent targeted searches triggered by the EP240219a alert identified
a faint, untriggered gamma-ray burst (GRB) in the archived data of Fermi/GBM,
Swift/BAT, Insight-HXMT/HE and INTEGRAL/SPI-ACS. The EP/WXT light curve reveals
a long duration of approximately 160 seconds with a slow decay, whereas the
Fermi/GBM light curve shows a total duration of approximately 70 seconds. The
peak in the Fermi/GBM light curve occurs slightly later with respect to the
peak seen in the EP/WXT light curve. Our spectral analysis shows that a single
cutoff power-law model effectively describes the joint EP/WXT-Fermi/GBM spectra
in general, indicating coherent broad emission typical of GRBs. The model
yielded a photon index of $\sim -1.70 \pm 0.05$ and a peak energy of $\sim 257
\pm 134$ keV. After detection of GRB 240219A, long-term observations identified
several candidates in optical and radio wavelengths, none of which was
confirmed as the afterglow counterpart during subsequent optical and
near-infrared follow-ups. The analysis of GRB 240219A classifies it as an X-ray
rich GRB with a high peak energy, presenting both challenges and opportunities
for studying the physical origins of X-ray flashes (XRFs), X-ray rich GRBs
(XRRs), and classical GRBs (C-GRBs). Furthermore, linking the cutoff power-law
component to non-thermal synchrotron radiation suggests that the burst is
driven by a Poynting flux-dominated outflow.
