Mpt Ext Tool Git Branch Ops

Git Branch Ops

Purpose

Perform Git branch operations safely and consistently when starting work.

Use When

• The user wants to create a new work branch.
• The user wants to start a feature, bugfix, hotfix, or backport branch.
• The task requires selecting the correct base branch from the branch type.
• The task requires checking for dirty worktrees or branch naming conflicts before branch creation.

Do Not Use When

• The task is to read or update Jira issues.
• The task is to generate a branch name from Jira title or description.
• The task is to open or update a pull request.
• The task is to perform destructive Git history operations such as reset, rewrite, or force-delete.

Inputs

• branch_type
  • feature
  • bugfix
  • hotfix
  • backport
• target_branch_name
• Optional remote_name
  • default: origin
• Installed shared package root when shared package guidance is needed:

${MPT_EXTENSION_SKILLS_HOME:-$HOME/.mpt-extension-skills}/current

Assumptions

• The command is running inside the target Git repository and local Git tooling is available.
• Remote access and Git credentials are configured well enough to read and update the selected base branch.
• The current repository state is suitable for branch creation, or the user is available to decide how to proceed when the worktree is dirty or a branch conflict is detected.

Workflow

1. Build repository context first.

• Read the target repository AGENTS.md once per session. If you already loaded it earlier in this session and still have its full contents, reuse them instead of re-reading; if the context was summarized or you are unsure it is complete, read it again. Do not pre-load shared docs in this step; read them lazily only when the repository points to them.
• Read repository-specific docs when they exist, because they may extend or override shared guidance.
• Read shared docs only when the repository explicitly points to them. Resolve those shared docs from ${MPT_EXTENSION_SKILLS_HOME:-$HOME/.mpt-extension-skills}/current when available; otherwise read them from the main branch of the shared GitHub repository.

2. Resolve the base branch from the branch type.

• For repositories that follow this package standard, read standards/branching.md using the shared-doc resolution rule from the repository context step, and use it as the source of truth for base-branch selection, hotfix/backport handling, and push conventions.
• Use the bundled deterministic script to resolve the base branch:

python3 "${MPT_EXTENSION_SKILLS_HOME:-$HOME/.mpt-extension-skills}/current/skills/mpt-ext-tool-git-branch-ops/scripts/resolve_base_branch.py" \
  --branch-type feature \
  --remote-name origin

• For feature and bugfix, the script returns main.
• For hotfix and backport, the script returns the latest remote release/* branch by numeric suffix.
• If the script reports that no remote release/* branch exists for hotfix or backport, stop and report the blocker.

3. Inspect the current Git state.

• Check the current branch and worktree status.
• If the worktree is dirty, stop and ask the user whether to continue.
• Check whether the target branch already exists locally or remotely.
• If the target branch already exists, stop and ask the user what to do.

4. Update the base branch locally.

• Switch to the resolved base branch.
• Update it with:

git pull <remote_name> <base-branch>

5. Create and switch to the target branch.

• Create the new branch from the updated local base branch:

git checkout -b <target_branch_name>

6. Report the result clearly.

• State which base branch was selected.
• State whether the branch was created successfully.
• If blocked, report the exact blocker: dirty worktree, branch naming conflict, or missing release branch.

Command Patterns

# Inspect repository state
git status --short --branch
git branch --list
git branch --remotes

# Resolve base branch
base_branch="$(python3 "${MPT_EXTENSION_SKILLS_HOME:-$HOME/.mpt-extension-skills}/current/skills/mpt-ext-tool-git-branch-ops/scripts/resolve_base_branch.py" \
  --branch-type <branch_type> \
  --remote-name <remote_name>)"

# Switch to base branch and update it
git checkout "${base_branch}"
git pull <remote_name> "${base_branch}"

# Create target branch
git checkout -b feature/MPT-1234/example-short-description

Guardrails

• Never continue past a dirty worktree without explicit user confirmation.
• Never hand-select the base branch when the bundled script can resolve it.
• Never silently reuse an existing local or remote branch with the same name.
• Never invent a release branch when none exists.
• Never rewrite history or delete branches as part of this skill.
• Never generate business-specific branch names from Jira content inside this tool skill; accept the target branch name as input.

Bundled Resources

• scripts/resolve_base_branch.py
  • Inputs: branch type and optional remote name
  • Output: base branch name, or JSON with base_branch
  • Runtime path: ${MPT_EXTENSION_SKILLS_HOME:-$HOME/.mpt-extension-skills}/current/skills/mpt-ext-tool-git-branch-ops/scripts/resolve_base_branch.py

Expected Outcome

The correct base branch is selected and updated, the target branch is created and checked out safely, or the operation stops with a clear blocker that requires user direction.