MCP Servers

ChatML supports the Model Context Protocol (MCP) for extending Claude's capabilities with custom tools.

Built-In MCP Server

ChatML runs a built-in MCP server that provides tools to Claude:

Tool	Description
`get_session_status`	Current session information and git state
`get_workspace_diff`	Git diff from the base branch
`get_recent_activity`	Recent git commits
`add_review_comment`	Add inline code review comments
`list_review_comments`	List existing review comments
`get_review_comment_stats`	Comment statistics per file
`get_linear_context`	Linear issue context for the current session
`start_linear_issue`	Start working on a Linear issue
`update_linear_status`	Update Linear issue status
`report_pr_created`	Report that a PR was created
`report_pr_merged`	Report that a PR was merged
`get_workspace_scripts_config`	Get workspace scripts configuration
`propose_scripts_config`	Propose scripts configuration changes

You can add your own MCP servers to extend Claude's toolset:

{
  "command": "npx",
  "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/dir"],
  "transport": "stdio"
}

MCP servers can also be configured per-workspace using a .mcp.json file in the repository root. This allows teams to share MCP configurations.