mcp-compliant filesystem tool exposure via json-rpc protocol
Exposes filesystem operations as standardized MCP Tools through a JSON-RPC 2.0 transport layer, allowing LLM clients to invoke file operations with structured request/response contracts. The server implements the MCP protocol primitives to register tool schemas, handle invocations, and return results in a format compatible with any MCP-aware client (Claude, custom agents, etc.). This abstraction decouples filesystem logic from transport concerns, enabling the same tool definitions to work across stdio, HTTP, or WebSocket transports.
Unique: Implements MCP's tool registration and invocation contract as a reference pattern, allowing any MCP-compatible client to discover and call filesystem operations without custom integration code. Uses TypeScript SDK's Server class to manage tool lifecycle and request routing.
vs alternatives: Provides protocol-level standardization that REST APIs or custom RPC layers don't offer, enabling zero-configuration integration with MCP-aware LLM clients like Claude.
configurable path-based access control with allowlist enforcement
Implements a security model where filesystem access is restricted to explicitly configured allowed paths (allowlist), preventing directory traversal and unauthorized file access. The server validates all incoming file paths against the allowlist before executing any operation, rejecting requests that attempt to access paths outside the permitted scope. Configuration is passed at server initialization time, allowing operators to define which directories or files LLM clients can interact with, with support for glob patterns or explicit path lists.
Unique: Uses a declarative allowlist model enforced at the tool invocation layer, validating paths before any filesystem operation executes. The reference implementation demonstrates this pattern clearly, making it easy for operators to understand and audit what access is granted.
vs alternatives: More explicit and auditable than capability-based security or role-based access control, making it easier for non-technical operators to understand what an LLM agent can and cannot access.
read file contents with text and binary encoding support
Provides a tool that reads file contents and returns them in the appropriate encoding (UTF-8 text or base64 binary), automatically detecting or accepting hints about file type. The implementation uses Node.js fs.readFile() with encoding parameters, returning text files as strings and binary files as base64-encoded strings to ensure JSON-RPC compatibility. The tool includes metadata about file size and encoding used, allowing clients to understand what they received.
Unique: Handles both text and binary files transparently by encoding binary data as base64, making it JSON-RPC-safe while preserving full file fidelity. The tool includes size metadata to help clients decide whether to process large files.
vs alternatives: More robust than simple text-only file readers because it gracefully handles binary files without corruption, and more transparent than opaque binary APIs because it explicitly encodes and reports what encoding is used.
write and create files with atomic write semantics
Provides a tool to write content to files, creating them if they don't exist or overwriting them if they do, with support for both text and base64-encoded binary content. The implementation uses Node.js fs.writeFile() which provides atomic semantics on most filesystems (write to temp file, then rename), ensuring partial writes don't corrupt files. The tool validates the target path against the allowlist and returns confirmation with file size written.
Unique: Leverages Node.js fs.writeFile() atomic semantics (temp-file-then-rename pattern) to ensure writes are durable and don't leave partial files, which is critical for code generation workflows where incomplete files break builds.
vs alternatives: More reliable than stream-based writes for small-to-medium files because atomic semantics prevent partial writes, and more transparent than opaque file APIs because it reports exact bytes written and supports both text and binary.
list directory contents with recursive traversal and filtering
Provides a tool to list files and subdirectories within a specified path, with optional recursive traversal to show the full directory tree. The implementation uses Node.js fs.readdirSync() or fs.promises.readdir() with recursive option, returning structured metadata for each entry (name, type, size, modification time). Clients can filter results by file type or pattern, and the tool respects the allowlist to prevent listing unauthorized directories.
Unique: Combines directory listing with optional recursive traversal and structured metadata output, allowing agents to build a mental model of project structure without multiple round-trips. The reference implementation shows how to safely traverse directories while respecting allowlist boundaries.
vs alternatives: More informative than simple ls-style output because it includes file sizes and modification times, and more efficient than requiring separate stat calls for each file because metadata is returned in a single operation.
delete files and directories with recursive removal option
Provides a tool to delete files or directories, with an optional recursive flag to remove non-empty directories and their contents. The implementation uses Node.js fs.rmSync() or fs.promises.rm() with recursive option, validating the target path against the allowlist before deletion. The tool returns confirmation of what was deleted and the number of files/directories removed.
Unique: Implements deletion as a controlled tool with explicit allowlist enforcement, preventing accidental or malicious removal of files outside the permitted scope. The reference implementation demonstrates safe patterns for exposing destructive operations to LLM agents.
vs alternatives: Safer than unrestricted shell access because the allowlist prevents deletion of system files, and more transparent than opaque deletion APIs because it reports exactly what was removed.
move and rename files with path validation and conflict handling
Provides a tool to move files from one location to another or rename them, with validation that both source and destination paths pass the allowlist. The implementation uses Node.js fs.renameSync() or fs.promises.rename(), which is atomic on most filesystems. The tool handles conflicts by either failing if the destination exists or optionally overwriting, depending on configuration.
Unique: Validates both source and destination against the allowlist, preventing moves that would escape the permitted scope. Uses atomic rename semantics to ensure moves are durable and don't leave partial state.
vs alternatives: More secure than unrestricted file operations because both paths are validated, and more reliable than manual copy-then-delete patterns because rename is atomic.
get file metadata and stats without reading content
Provides a tool to retrieve file or directory metadata (size, modification time, permissions, type) without reading the full file content, using Node.js fs.statSync() or fs.promises.stat(). This is efficient for large files where only metadata is needed. The tool returns structured information about file type, size in bytes, creation/modification/access times, and permission bits.
Unique: Separates metadata retrieval from content reading, allowing agents to make intelligent decisions about which files to process without the overhead of reading large files. The reference implementation demonstrates this as a distinct tool rather than bundling it with read operations.
vs alternatives: More efficient than reading file content just to check size or modification time, and more transparent than opaque stat APIs because it returns all available metadata in a structured format.
+2 more capabilities