Most existing program performance tools for parallel syste ms are based on built-in instrumentation engines that are no t based on a standard and therefore lack portability to differ ent programming languages. Commonly instrumentation engi nes are often bound to specific compilers for specific programming languages, becoming a limiting factor at some stage of a performance tool‘s lifecycle, restricting its applicabil ity and impeding further developments. As instrumentation engines are often bound to specific compilers for specific programming languages, extending them to additional programming languag es comes with a high cost, which in turn prevents portability ofhigher-level performance analysis tools. In previous work we proposed a standardized intermediate re presentation (SIR) for parallel and sequential programs, c rently covering procedural and object oriented languages.A SIR decouples a performance tool from specific instrumenta tion engines under the assumption that the proposed SIR is suppor ted by a large variety of instrumentation engines. In this re port we introduce an XML-based language for monitoring and instr umentation requests named MIR, which in combination with the SIR defines a comprehensive, portable interface betweenhigher-level performance analysis tools and instrumentat ion engines.