2026ApJ...996..126S

Understanding the impact of spectral coverage on parameter recovery is critical for accurate interpretation of blazar spectra. In this study, we examine how the data coverage influences the reliability of parameter estimation within the one-zone synchrotron self-Compton (SSC) framework. Using OJ 287, TXS 0506+056, and Mrk 421 as representative of the low, intermediate, and high synchrotron peak (LSP, ISP, and HSP) subclasses, respectively, we generate synthetic spectral energy distributions based on their best-fit models and perform 1000 fits for each of the 21 observational configurations per source type. Our analysis quantifies the coverage probability for all model parameters, such as the magnetic field strength and the electron luminosity, and reveals that different blazar subclasses exhibit distinct sensitivities to spectral gaps. For LSPs, a minimal dataset comprising optical/UV, X-ray, and GeV γ-ray bands is sufficient for robust parameter inference. In contrast, ISPs and HSPs require broader spectral coverage to constrain the physical parameters. For ISP, we find that reliable parameter recovery can be achieved with two different minimal band combinations: (i) X-ray, high-energy (HE) γ-ray, and very HE γ-ray data, or (ii) optical/UV, X-ray, and HE γ-ray data. For HSPs, the minimal configuration enabling reliable parameter recovery includes the optical/UV, X-ray, and very high energy γ-ray bands. We discuss the role of very high energy γ-ray observations, showing that they significantly enhance parameter recovery for HSPs. Our results provide practical guidelines for designing optimized multiwavelength observation campaigns and for assessing the robustness of SSC model inferences under incomplete spectral coverage.