This study presents a TAPP-based fluorescent sensor for diethylchlorophosphate (DCP), a surrogate for sarin, addressing the critical challenge of detecting nerve agents. The sensor can form a reversible weak bond interaction with the PO group in sarin by using the reversible weak bond complexation mechanism in the porphyrin cavity, which is the key to realize the reversible function of the sensor. In this study, we constructed a fluorescence probe that combines the advantages of physical process and chemical reaction process sensing, which not only ensures selectivity, but also realizes continuous and reversible real-time detection of DCP. The sensor demonstrates excellent photochemical stability and sensitivity, with an actual detection limit of 10 ppt and a theoretical detection limit of 1 ppt. In addition, it can differentiate challenging interferents like HCl through response kinetics, offering a practical, cost-effective, and environmentally sustainable solution for nerve agent detection in high-risk environments.