High-Performance MCP Server

A high-performance, modular Model Context Protocol (MCP) server built with TypeScript and the modern MCP v2 SDK (@modelcontextprotocol/server). Features safe-by-default security profiles, profile-aware server instructions, modular MCP prompts, allowlisted workspace inspection with opt-in guarded text mutation, SSRF-hardened network access, Streamable HTTP, Stdio transport, reusable worker thread pooling, production LRU caching with single-flight stampede protection, and structured telemetry.

Project Status: Public Preview (v0.5.0)

[!NOTE] Status: 0.5.0 Public Preview. This package provides safe-by-default MCP tools, read-only workspace inspection, opt-in guarded workspace mutation and network access, worker request cancellation, normalized progress reporting, and high-performance worker execution. Requires Node.js >= 22.0.0.

Compatibility: The new v0.5 options are additive. Existing callers that omit contextLines, maxDepth, createParents, and fetch_url.method retain their established default semantics. v0.5 also includes an intentional create-mode publication hardening: filesystems that cannot provide hard-link no-clobber publication now fail closed instead of using the previous check-then-rename fallback.

Features

• Modern MCP v2 Architecture: Built natively on @modelcontextprotocol/server with standard JSON Schema draft 2020-12 validation and full 2026-07-28 protocol support.
• Dual Transport Support: Run seamlessly over standard input/output (stdio) or modern Streamable HTTP (node:http + /mcp).
• Profile-Aware Server Instructions: Dynamic server instructions that guide connected LLMs on recommended workflows, tool sequencing, and safety boundaries based on the active profile.
• Modular MCP Prompts: Reusable task prompts (explore_workspace, find_and_explain, review_file, trace_symbol) exposed exclusively in workspace, workspace_write, and all profiles.
• MCP-Native Workspace Completions: Autocompletes logical rootId values for every workspace prompt and the workspace resource template without enumerating files or exposing host paths.
• Safe-by-Default Tool Profiles: Default safe profile exposes zero filesystem, network, or hardware inspection. Filesystem mutation and outbound network access require explicit workspace_write/network (or all) opt-in.
• Workspace Security & Host Path Privacy: Secure allowlisted directory access with path traversal and symlink escape prevention, logical root mapping (root-1, root-2), bounded text operations, and binary file protection without exposing host absolute paths to clients or models. The workspace profile remains read-only; guarded mutation is isolated to workspace_write and all.
• Workspace Search & Exploration: Fast, bounded literal file and text search (search_files, search_text) with ignored directory defaults, bounded concurrency (SEARCH_CONCURRENCY = 8), coordinate mapping, optional bounded context lines (contextLines: 0..10), and client cancellation.
• Recursive Directory Listing: Bounded recursive subdirectory traversal (list_directory with maxDepth: 1..5) using breadth-first search and normalized relative paths up to a global 500-entry cap.
• Guarded Workspace Mutation & Safe Parent Creation: Transactional editing (edit_text_file) and atomic no-clobber creation (write_text_file) with optional safe segment-by-segment parent creation (createParents), optimistic SHA-256 concurrency control, and optional client confirmation.
• Safe Network Fetch & Metadata: Outbound HTTP/HTTPS fetching (fetch_url) protected by multi-layered SSRF defenses, DNS rebinding mitigation, port allowlists, conditional response caching, and lightweight HTTP HEAD metadata inspection.
• Worker Thread Pool with Cancellation: Offload CPU-heavy tasks from the Node.js event loop with automatic lifecycle recovery, `AbortSi

... View full README on GitHub