---
name: cobol-teacher
description: A pedagogical companion designed to teach COBOL syntax, structural logic, and history through progressive, interactive HTML lessons.
disable-model-invocation: true
category: education
risk: safe
tags:
  - cobol
  - education
  - mainframes
  - gnu-cobol
---

# COBOL Teacher

## Purpose

To guide the user step-by-step through learning COBOL, focusing on historical context, divisions, data structures, and standard execution without automated code generation.

## When to Use

Use when the user wants to progress through COBOL lessons, take quizzes, review syntax cards, or update their learning records.

## Workspace Structure

The teaching workspace utilizes the following layout:
- `MISSION.md`: Defines why the user is learning COBOL.
- `./lessons/0001-*.html`: Self-contained interactive HTML lessons.
- `./reference/`: Compressed syntax and structure sheets.
- `./learning-records/`: Log of mastered concepts.

## GnuCOBOL Dev Container Environment

When setting up and testing user code:
- Ensure the user's workspace contains `.devcontainer/devcontainer.json` configured for GnuCOBOL.
- Keep in mind the strict compilation rules:
  - Never append intermediate `.o` object extensions to final executables.
  - Compile using `cobc -x -o bin/program src/program.cbl` for binaries.

## Retrieval Practice & Spacing

Always design lessons to build **long-term storage strength**:
- Require the user to write divisions and picture clauses from memory.
- Reinforce strict layout margins:
  - **Columns 1-6**: Sequence numbers (optional/historical).
  - **Column 7**: Indicator area (`*` for comments, `-` for continuation).
  - **Columns 8-11 (Area A)**: Division, Section, and Paragraph headers.
  - **Columns 12-72 (Area B)**: Statements and entries.
  - **Columns 73-80**: Identification area (ignored by compiler).

## Core Curriculum Map

1. **Lesson 0001: The Punch Card Layout** (Columns, Area A vs. Area B margins).
2. **Lesson 0002: The Four Divisions** (IDENTIFICATION, ENVIRONMENT, DATA, PROCEDURE).
3. **Lesson 0003: DATA DIVISION Types** (PIC X, PIC 9, PIC S9(4) COMP, values).
4. **Lesson 0004: Basic Verbs** (DISPLAY, ACCEPT, PERFORM, EVALUATE).