Filesystem MCP Server

The Filesystem MCP server is maintained by Anthropic. It provides primitive file-system tools (read, write, list, search) that the Planner Agent uses to handle user uploads, write supplementary SUMO configuration files, and inspect generated artifacts.

Official documentation

modelcontextprotocol/servers — Filesystem

github.com/modelcontextprotocol/servers/tree/main/src/filesystem

https://github.com/modelcontextprotocol/servers/tree/main/src/filesystem

Tools used by AgentSUMO

The server exposes thirteen tools across three categories, matching the layout in Figure 3 of the paper.

Category	Tool	Purpose
Read	read_text_file	Read a text file’s contents.
Read	read_media_file	Read a binary media file (returns base64).
Read	read_multiple_files	Batch-read several files in one call.
Read	list_directory	List the entries of a directory.
Read	list_directory_with_sizes	List entries together with file sizes.
Read	directory_tree	Recursive JSON tree of a directory.
Read	search_files	Find files by name pattern.
Read	get_file_info	Retrieve file metadata (size, mtime, permissions).
Read	list_allowed_directories	List the directories the server is configured to access.
Write	write_file	Write or overwrite a file.
Write	edit_file	Apply line-based edits to an existing file.
Write	create_directory	Create a directory (idempotent).
Manage	move_file	Move or rename a file.

How AgentSUMO uses it

The Filesystem MCP server is launched at AgentSUMO startup with access restricted to the project working directory: the output/ tree, the agentsumo/agent/additional_files_guide/ markdown guides, and any user-supplied data files explicitly placed in the project tree.

Three concrete patterns:

1. Reading user uploads. When a user provides an OD matrix as a CSV file, the Planner Agent reads it via read_text_file to verify column structure and coordinate format before passing the path to trip_generate.

2. Writing supplementary XML configurations. Many SUMO policy interventions are temporal or conditional (e.g., time-based road closures, variable speed limits, fleet composition changes). These are implemented through supplementary XML files loaded alongside the network at simulation time. The agent writes these files via write_file, guided by three markdown guides bundled with AgentSUMO (rerouter.md, vss.md, vtype.md). The generated files are passed to sumo_runner through its additional_files parameter.

3. Inspecting generated artifacts. After tool execution, the agent uses list_directory and read_text_file to verify output and diagnose errors before reporting back to the user.