What is cobol-o-matic CLAUDE.md?

A guide for a tool that examines COBOL applications and turns their structure into organized Markdown documents. COBOL is a programming language still used in many older business systems.

Maintaining the reverse-engineering tool, its parser, staged analysis process, saved state, validation, logging, and specialist agents.

It helps developers understand unfamiliar COBOL code without manually tracing the whole application.

How dsheard/cobol-o-matic configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to dsheard/cobol-o-matic. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/dsheard/cobol-o-matic/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/dsheard/cobol-o-matic

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/dsheard/cobol-o-matic/claude-md/github.svg)](https://agentmods.dev/instructions/dsheard/cobol-o-matic/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/dsheard/cobol-o-matic/claude-md"><img src="https://agentmods.dev/badge/instructions/dsheard/cobol-o-matic/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/dsheard/cobol-o-matic/claude-md"><img src="https://agentmods.dev/badge/instructions/dsheard/cobol-o-matic/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 1,998 This file is loaded in full into every session.

When invoked 1,998 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.01998	$0.01998
Opus 5.5	$0.00799	$0.00799
Sonnet 5.5	$0.00400	$0.00400
Haiku 4.5	$0.00200	$0.00200

Measured 2mo ago against content hash 9b3948aaf7c0, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

cobol-o-matic CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 164 lines

How it starts

The opening of the file, as written. The whole thing — 164 lines — stays where its author put it; the contents beside it link to each section on GitHub.

COBOL Reverse Engineering Tool

An agentic tool that reverse-engineers COBOL applications into structured markdown artifacts. Uses the Claude Agent SDK to spawn specialised subagents.

Directory Layout

analyse.py       # Thin CLI entry point
orchestrator/                   # Core Python package
├── __init__.py                 #   Shared constants and utilities
├── models.py                   #   Dataclasses (Discovery, Paragraph, Chunk, Manifest)
├── state.py                    #   State persistence and convergence tracking
├── parser.py                   #   Deterministic COBOL structural parser
├── stager.py                   #   Chunk staging pipeline
├── validator.py                #   Deterministic artifact validation
├── tracing.py                  #   JSONL event logging and optional OTEL tracing
├── config.py                   #   Config loading, defaults, workspace scaffolding
├── agents.py                   #   Agent construction, SDK interaction, critic
├── runner.py                   #   Run strategies, phased execution, sweep
└── cli.py                      #   CLI argument parsing, command handlers, main()
prompts/                        # Agent prompt builders (one per worker)
├── _helpers.py                 #   Shared helpers (_source_context, _read_template, etc.)
├── inventory.py                #   Inventory worker prompt
├── data.py                     #   Data worker prompt
├── business_rules.py           #   Business rules worker prompt (+ chunked variant)
├── flow.py                     #   Flow worker prompt
├── integration.py              #   Integration worker prompt
├── requirements.py             #   Requirements-deriver prompt
├── test_specs.py               #   Test-specs-deriver prompt
├── implementation.py           #   Implementation-plan-deriver prompt
├── critic.py                   #   LLM critic prompt for corrective passes
└── orchestrator.py             #   Orchestrator prompt and helpers
templates/                      # Output artifact templates (frontmatter schema + sections)
examples/                       # Reference configs for open-source COBOL apps
workspace/                      # Analysis workspace (agents run here)
├── config.yaml                 #   Config: source paths, output dir, settings
├── CLAUDE.md                   #   Agent-focused output conventions
├── source/                     #   COBOL input files
├── output/                     #   Generated markdown artifacts
├── staging/                    #   Chunked files for large programs
├── state/                      #   Run state JSON files (convergence tracking)
└── logs/                       #   JSONL event logs and agent transcripts

Read the full file on GitHub · 164 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 164 lines · 1,998 tokens per session scan A 9b3948aaf7c0

Subscribe to this mod's changes

cobol-o-matic CLAUDE.md is an instructions file published in the GitHub repository dsheard/cobol-o-matic (6 stars, last pushed 7mo ago), licensed MIT. It adds 1,998 tokens to every session, about $0.0080 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Languages ai-agents claude cobol legacy-modernization mainframe requirements-extraction

cobol-o-matic CLAUDE.md next to 6 instructions from other repositories
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cobol-o-matic CLAUDE.mddsheard/cobol-o-matic	Instructions file	6	7mo ago	MIT	A	1,998	Claude Code
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cobol-o-matic: Instructions file for Claude Code