git_branch

Instructions

Implementation Reference

• src/git/src/mcp_server_git/server.py:77-93 (schema)

  Pydantic model defining the input schema for the git_branch tool: repo_path, branch_type, optional contains/not_contains commit SHAs.

  class GitBranch(BaseModel):
      repo_path: str = Field(
          ...,
          description="The path to the Git repository.",
      )
      branch_type: str = Field(
          ...,
          description="Whether to list local branches ('local'), remote branches ('remote') or all branches('all').",
      )
      contains: Optional[str] = Field(
          None,
          description="The commit sha that branch should contain. Do not pass anything to this param if no commit sha is specified",
      )
      not_contains: Optional[str] = Field(
          None,
          description="The commit sha that branch should NOT contain. Do not pass anything to this param if no commit sha is specified",
      )

• src/git/src/mcp_server_git/server.py:96-109 (registration)

  Enum registration of 'git_branch' as GitTools.BRANCH.

  class GitTools(str, Enum):
      STATUS = "git_status"
      DIFF_UNSTAGED = "git_diff_unstaged"
      DIFF_STAGED = "git_diff_staged"
      DIFF = "git_diff"
      COMMIT = "git_commit"
      ADD = "git_add"
      RESET = "git_reset"
      LOG = "git_log"
      CREATE_BRANCH = "git_create_branch"
      CHECKOUT = "git_checkout"
      SHOW = "git_show"
  
      BRANCH = "git_branch"

• src/git/src/mcp_server_git/server.py:430-441 (registration)

  Tool registration in list_tools() listing GitTools.BRANCH with its schema.

      Tool(
          name=GitTools.BRANCH,
          description="List Git branches",
          inputSchema=GitBranch.model_json_schema(),
          annotations=ToolAnnotations(
              readOnlyHint=True,
              destructiveHint=False,
              idempotentHint=True,
              openWorldHint=False,
          ),
      )
  ]

• src/git/src/mcp_server_git/server.py:258-290 (handler)

  Handler function that executes the 'git_branch' tool logic: validates inputs, then calls repo.git.branch() with appropriate flags.

  def git_branch(repo: git.Repo, branch_type: str, contains: str | None = None, not_contains: str | None = None) -> str:
      # Defense in depth: reject values starting with '-' to prevent flag injection
      if contains and contains.startswith("-"):
          raise BadName(f"Invalid contains value: '{contains}' - cannot start with '-'")
      if not_contains and not_contains.startswith("-"):
          raise BadName(f"Invalid not_contains value: '{not_contains}' - cannot start with '-'")
  
      match contains:
          case None:
              contains_sha = (None,)
          case _:
              contains_sha = ("--contains", contains)
  
      match not_contains:
          case None:
              not_contains_sha = (None,)
          case _:
              not_contains_sha = ("--no-contains", not_contains)
  
      match branch_type:
          case 'local':
              b_type = None
          case 'remote':
              b_type = "-r"
          case 'all':
              b_type = "-a"
          case _:
              return f"Invalid branch type: {branch_type}"
  
      # None value will be auto deleted by GitPython
      branch_info = repo.git.branch(b_type, *contains_sha, *not_contains_sha)
  
      return branch_info

• src/git/src/mcp_server_git/server.py:570-580 (registration)

  Dispatch in call_tool() that maps 'git_branch' name to the git_branch() handler function, passing extracted arguments.

  case GitTools.BRANCH:
      result = git_branch(
          repo,
          arguments.get("branch_type", 'local'),
          arguments.get("contains", None),
          arguments.get("not_contains", None),
      )
      return [TextContent(
          type="text",
          text=result
      )]