This paper examines interacting dark energy models within the Chevallier-Polarski-Linder (CPL) parametrization, emphasizing both theoretical structure and observational viability. Two commonly adopted interaction terms are considered: $Q=\beta H{\rho }_{\mathrm{de}}$ and $Q=\beta H{\rho }_{\mathrm{c}}$. We derive exact analytic solutions that describe how the dark sector evolves. These solutions involve incomplete gamma functions and reveal a nontrivial mathematical structure that is often missed in numerical analyses. We perform a Bayesian analysis using current cosmological observations, including the Hubble parameter, Type Ia supernovae, baryon acoustic oscillations, and CMB data. Relative to the non-interacting CPL scenario, the interacting model with $Q=\beta H{\rho }_{\mathrm{de}}$ yields a modestly improved fit, as indicated by the Akaike information criterion. However, the Bayesian information criterion penalizes increased model complexity, leading to a continued preference for $\mathrm{\Lambda }$ cold dark matter. In contrast, the interaction model that depends on dark matter density does not provide observational support. The preferred interacting scenario indicates that the dark energy equation of state evolves dynamically, transitioning from an effective phantom regime at high redshift to quintessencelike behavior at late times. Further analysis suggests the possibility of a future transition from accelerated to decelerated expansion, primarily associated with the reconstructed CPL dynamics, while the interaction alters the detailed evolution of the dark sector and the precise transition epoch. These findings suggest that interacting dark energy models within the CPL framework enrich the standard cosmological model by introducing more diverse phenomenology while maintaining consistency with current observations.

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• Cosmological parameters
• Dark energy
• Evolution of the Universe
• Bayesian methods
• Monte Carlo methods