Architecture - Structural and Behavioral Models

Provides reconstructed structural views derived from code, copybook, and interface analysis, including system context, data flow, program dependencies, and shared record layouts, establishing system coupling and processing pipelines.

• copybook-relationship-diagram: Identifies shared COBOL copybooks and their program usage, organizing them by functional category and exposing structural coupling clusters, including IMS-related groups and widely shared assessment record layouts.

• data-flow-diagram: Traces end-to-end data movement from external inputs through staged batch pipelines to final valuation and reporting outputs, including explicit generation chains and cross-pipeline shared data sets.

• program-dependency-diagram: Maps dependencies using direct CALL relationships and file-mediated handoffs, showing that most operational coupling occurs through sequential file pipelines, with only one true subprogram call.

• system-context-diagram: Defines system boundaries, external data sources, actors, major processing phases, and output products in a top-level operational context model.

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Programs - Domain and Behavior Catalog

Establishes a domain-organized program inventory with verified purpose, interfaces, dependencies, database usage, and processing roles derived from program headers and source inspection.

• program-index: Provides a consolidated inventory of all identified programs grouped by domain prefix, with purpose summaries and classification notes supporting scoping and impact assessment.

• ASCOE-programs: Documents Certificate of Error processing programs that extract COE data from IMS and produce COE work files and reports used by downstream recalculation steps.

• ASHMA-programs: Describes Homestead and Senior Freeze programs that build and update exemption datasets and compute freeze base and tax-difference values across IMS and sequential processing variants.

• ASREA-programs: Covers core assessment and valuation programs responsible for assessment master processing, valuation computation, equalization application, and frozen valuation preparation.

• ASSRQ-programs: Documents service request and mixed-class (circulator-related) processing programs, including closely related variants and code paths marked as disabled or superseded.

• CLREB-programs: Describes the equalization factor edit and validation program that reads factor inputs, performs validation, and produces the equalization factor file used by downstream valuation programs.

• CLRTM-programs: Documents clerk tax rate and valuation aggregation pipeline programs that perform TIF calculations, agency and division mapping, frozen agency updates, and PTELL-related reporting.

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Requirements - Business and Regulatory Logic Extraction

Documents reconstructed requirements, rule logic, statutory mappings, and embedded regulatory values identified directly from implemented program behavior.

• requirements-overview: Provides a structured reconstruction of business and regulatory requirements derived from program logic, organized by valuation, equalization, exemption, TIF, PTELL, and correction processing areas.

• business-rules: Catalogs rule-level computational and decision logic extracted directly from COBOL programs, including formulas, thresholds, classification rules, and conditional treatments tied to specific code locations.

• hardcoded-values: Enumerates embedded constants, thresholds, limits, status codes, and year ranges present in source code, with classification by update and modernization risk.

• regulatory-references: Maps implemented logic to governing Illinois property tax statutes and regulatory frameworks, identifying where PTELL, TIF, equalization, exemption, and COE rules are encoded in behavior.

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Runtime - Execution and Processing Flow

Defines the inferred batch execution phases and run sequence based on file dependencies, program I/O relationships, and functional staging.

• execution-order: Reconstructs the intended batch execution phases and program run sequence from file dependencies and functional roles, explicitly noting that original job control streams were not available and the flow is inferred.

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