Worked on the mujoco-wasm repository to enhance the reliability of data transfer between MJX and MuJoCo, focusing on robust error handling and comprehensive testing. Addressed a bug involving shape mismatches by implementing validation checks within the get_data_into function, ensuring that incompatible data shapes are detected early and communicated clearly to users. Developed targeted unit tests in Python to verify that shape errors raise appropriate exceptions, thereby reducing the risk of silent failures during data handling. Emphasized improving user-facing error messages and increasing test coverage, which collectively strengthened the overall stability and maintainability of the wasm data interface.