feat(git-master): add GIT_MASTER=1 env prefix for all git commands

[devxoul]

Summary

• Add git_env_prefix config to git_master config section (default: "GIT_MASTER=1", set to "" to disable).
• When enabled, inject a mandatory instruction into the git-master skill template requiring all git commands to be prefixed with the configured env variable (e.g., GIT_MASTER=1 git commit ...).
• Commit footer examples in the skill also respect the prefix.

Why This Matters

The git-master skill enforces atomic commits, conventional commit style, history analysis, and careful git discipline — but there is no way to guarantee the agent always loads it. This feature bridges that gap by giving hooks a reliable signal to detect (or enforce) git-master usage.

The primary motivation: a hook (OpenCode, Claude Code, or even git) can inspect git commands and reject them unless GIT_MASTER=1 is in the command, effectively forcing the agent to always load the git-master skill for any git operation. This ensures atomic commits, style detection, and all git-master discipline is always applied — no more silent fallback to unstructured commits.

Use Cases

1. Enforce git-master skill loading via hooks

The killer use case. A tool.execute.before hook (works in both OpenCode and Claude Code) detects git commands in Bash tool calls and rejects them if GIT_MASTER=1 prefix is missing — forcing the agent to load the git-master skill before touching git:

// OpenCode / Claude Code hook: tool.execute.before
if (toolName === "Bash" && command.includes("git ") && !command.includes("GIT_MASTER=1")) {
  return { error: "Load git-master skill before running git commands." }
}

This guarantees every agent git operation goes through git-master's atomic commit analysis, conventional commit enforcement, and history-aware style detection.

2. Git hooks also work

Since the env var is set at the shell level, traditional git hooks can see it too. A pre-commit hook can enforce stricter rules only for agent commits:

#!/bin/bash
# .git/hooks/commit-msg — stricter rules for agent commits
if [ "$GIT_MASTER" = "1" ]; then
  if ! grep -qE "^(feat|fix|refactor|test|docs|chore)(\(.+\))?: .+" "$1"; then
    echo "ERROR: git-master commits must use conventional commit format."
    exit 1
  fi
fi

3. Audit trail / observability

Scripts or CI pipelines can distinguish agent-made commits from human commits. Since the env var is present during the git operation, hooks can tag commits with metadata:

#!/bin/bash
# .git/hooks/prepare-commit-msg
if [ "$GIT_MASTER" = "1" ]; then
  git interpret-trailers --in-place --trailer "Agent: git-master" "$1"
fi

4. Customizable prefix for team integration

Teams can set their own prefix to integrate with existing tooling:

{
  "git_master": {
    "git_env_prefix": "AGENT_COMMIT=1"     // match your team's conventions
    // "git_env_prefix": "AI_AUTHORED=true" // or integrate with AI detection tools
    // "git_env_prefix": ""                 // disable entirely
  }
}

Roadmap

A follow-up PR can address the "enforce git-master loading" option directly — e.g., a built-in hook that rejects git operations without the skill loaded. But it's better to land this bridge first; it lays the groundwork that the enforce feature will build on.

Configuration

// .opencode/oh-my-opencode.jsonc
{
  "git_master": {
    "git_env_prefix": "GIT_MASTER=1"  // default, set to "" to disable
  }
}

Changes

• src/config/schema/git-master.ts — Add git_env_prefix field to schema with "GIT_MASTER=1" default.
• src/features/opencode-skill-loader/git-master-template-injection.ts — Inject env prefix section into skill template when enabled. Refactor injection logic into helper functions.
• src/features/opencode-skill-loader/git-master-template-injection.test.ts — New: unit tests for env prefix injection (default value, disabled via empty string, custom value).
• src/features/opencode-skill-loader/skill-content.test.ts — Update existing tests to include git_env_prefix field.

Testing

bun run typecheck
bun test src/features/opencode-skill-loader/git-master-template-injection.test.ts
bun test src/features/opencode-skill-loader/skill-content.test.ts

[cubic-dev-ai]

No issues found across 4 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Auto-approved: The PR safely introduces a new configuration option with comprehensive tests. The logic for template injection is robust and handles default, custom, and disabled states correctly.}