claude-vb6-skills

Claude Code skills for maintaining and developing Visual Basic 6 codebases. Covers conventions, error handling (CSEH), ADO via late binding (MSSQL and PostgreSQL), manual stack tracing, and common utility patterns — calibrated against real production VB6 code from long-lived projects.

What's inside

Five skills, each loaded on demand when the conversation matches its scope:

Each skill ships with reference files (reference/) containing reusable .bas modules and catalog documents that the skill points to when relevant.

Six principles in one paragraph

1. Preserve case in existing code — VB6 is case-insensitive, diff tools

are not.

1. Hungarian notation with scope prefix (m_/m/g) plus type prefix

(str/int/lng/bln/...).

1. CSEH for error handling, with EnterMethod/ExitMethod on both

success and error paths and numbered lines for Erl.

1. Late-binding ADO (As Object + CreateObject), with ConnectionTimeout

mandatory, the disconnected-recordset pattern for reads, and parameters for every user-supplied value.

1. Manual stack tracing through a module-level array, pushed/popped by

EnterMethod/ExitMethod, with optional parameter serialization and automatic WMI process dump on automation errors.

1. Reuse utility wrappers (MsgBoxCritical, fg_isNull, IsValidCNPJ,

PadLeft, ...) — search before writing a new one.

Installation

Option A — install as a Claude Code plugin (recommended)

Add this repo as a marketplace, then install the plugin:

/plugin marketplace add alexcassol/claude-vb6-skills
/plugin install claude-vb6-skills@vb6-skills

The skills auto-activate when their triggers appear in the conversation (opening a .bas or .cls file, writing On Error GoTo, building an ADO command, etc.).

Option B — drop CLAUDE.md into the project

For projects that don't install plugins, copy CLAUDE.md to the root of the VB6 project. It is a condensed version of the same conventions and loads automatically in every Claude Code conversation in that project.

The plugin version is richer (each skill has its own deep documentation plus reference files); CLAUDE.md is a single-file summary suitable for adding to a project repo as a permanent context file.

Customization

These skills capture patterns the author has used across long-lived codebases. Some details vary per project:

• Multibank support: examples show both MSSQL (@param) and PostgreSQL

(in_param/out_param). If your project is single-database, ignore the alternative branch.

• Module names: examples use generic English names (modDB, modUtils).

Your project may use Portuguese or domain-specific names — Claude will match the existing convention when editing.

• Function library: the vb6-utilities catalog lists common helpers

(fg_isNull, MsgBoxCritical, IsValidCNPJ, etc.). Your project's helpers may have different names — point Claude at your actual utility module when relevant.

• CSEH offset numbering: when a procedure originates an error it uses

vbObjectError + <offset> (a re-raised/propagated error keeps its original Err.Number). Allocate offset ranges however your team prefers (per-procedure, per-category, etc.).

• Trace pattern: the modLog.bas reference is self-contained and

copy-paste ready, but assumes Microsoft Scripting Runtime is referenced and an fg_InIDE() function exists. Both are described in the skill.

Project-specific overrides go in CLAUDE.md (the section marked "Project-specific overrides" at the bottom).

Repository layout

claude-vb6-skills/
├── .claude-plugin/
│   ├── marketplace.json
│   └── plugin.json
├── skills/
│   ├── vb6-guidelines/
│   │   └── SKILL.md
│   ├── vb6-error-handling/
│   │   ├── SKILL.md
│   │   └── reference/cseh-styles.md
│   ├── vb6-ado-late-binding/
│   │   ├── SKILL.md
│   │   └── reference/
│   │       ├── ado-constants.bas
│   │       └── command-pattern.bas
│   ├── vb6-trace-pattern/
│   │   ├── SKILL.md
│   │   └── reference/modLog.bas
│   └── vb6-utilities/
│       ├── SKILL.md
│       └── reference/helpers-catalog.md
├── CLAUDE.md
├── EXAMPLES.md
├── README.md
└── LICENSE

License

MIT — see LICENSE.