Substitute Eraser

Scan existing codebases for placeholder tokens. Generate remediation plan.

Purpose

Audit existing files for substitution tokens (TODO, FIXME, placeholder, mock, etc.) and produce actionable remediation plan. Distinct from accept-no-substitutes which validates agent output.

Scope: Existing Files

This skill scans what already exists:

• Source code files
• Configuration files
• Documentation with stale placeholders
• Test fixtures that leaked into production

Complements accept-no-substitutes (output validation).

Trit Assignment

• Trit: -1 (MINUS/VALIDATOR)
• Hue: 270° (violet - deep scan)
• Role: Codebase auditor, technical debt detector

Scan Workflow

1. Discovery

# Scan current directory
just substitute-scan .

# Scan specific path
just substitute-scan src/

2. Classification

| Severity | Tokens | Action | |----------|--------|--------| | CRITICAL | TODO, FIXME, placeholder, xxx | Must fix before merge | | WARNING | mock-, fake-, stub-* (outside tests) | Review context | | INFO | example_, demo_ | Document or remove |

3. Remediation Report

Output format:

SUBSTITUTE ERASER REPORT
========================
Scanned: 142 files
Found: 23 substitutions

CRITICAL (7):
  src/auth.py:42      TODO: implement token refresh
  src/api.py:118      placeholder value
  src/db.py:55        FIXME: race condition
  ...

WARNING (12):
  src/service.py:30   mock_client (not in test file)
  ...

INFO (4):
  README.md:15        example_config
  ...

REMEDIATION PLAN:
1. [CRITICAL] src/auth.py:42 - Implement token refresh logic
2. [CRITICAL] src/api.py:118 - Replace placeholder with actual value
...

Context-Aware Exceptions

Acceptable Locations

| Pattern | Acceptable In | |---------|---------------| | mock-*, fake-*, stub-* | *_test.py, test_*.py, /tests/ | | example_* | README.md, /docs/, /examples/ | | demo_* | /demo/, documentation | | TODO | Issue tracker references with ID |

Exception Syntax

Mark intentional placeholders:

# SUBSTITUTE-OK: mock used for test isolation
mock_client = MockHTTPClient()

Commands

# Full scan with report
just substitute-scan <path>

# Critical only (CI mode)
just substitute-critical <path>

# Generate remediation tasks
just substitute-tasks <path> --output=github  # GitHub issues
just substitute-tasks <path> --output=linear  # Linear tickets
just substitute-tasks <path> --output=todo    # TODO file

# Interactive fix mode
just substitute-fix <path>

Integration with GF(3)

Operates as MINUS (-1) in audit triads:

substitute-eraser(-1) + code-generator(+1) + review-coordinator(0) = 0

Emits rejection signal when scan finds violations above threshold.

Additional Resources

Reference Files

• references/patterns.md - Detection regex patterns (shared with accept-no-substitutes)
• references/remediation.md - Fix strategies per token type

Scripts

• scripts/scan.py - Main scanning script
• scripts/report.py - Report generation

SDF Interleaving

This skill connects to Software Design for Flexibility (Hanson & Sussman, 2021):

Primary Chapter: 10. Adventure Game Example

Concepts: autonomous agent, game, synthesis

GF(3) Balanced Triad

substitute-eraser (+) + SDF.Ch10 (+) + [balancer] (+) = 0

Skill Trit: 1 (PLUS - generation)

Secondary Chapters

• Ch6: Layering
• Ch4: Pattern Matching
• Ch2: Domain-Specific Languages

Connection Pattern

Adventure games synthesize techniques. This skill integrates multiple patterns.