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Naman Khater
Naman Khater

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How I gave GitHub Copilot real code intelligence with a local MCP server

#ai #github #mcp #tooling

The problem: Copilot doesn't know your codebase

If you've used GitHub Copilot or Cursor on a large project, you've probably noticed that AI suggestions get worse as your codebase grows. The AI can see your open files, maybe grep through some others, but it doesn't actually understand the structure — where functions are defined, what calls what, how modules connect.

I ran into this building a 16-service TypeScript platform. Copilot would hallucinate function signatures, miss cross-file references, and suggest imports that didn't exist. The AI was powerful, but context-blind.

The fix: structured code context via MCP

MCP (Model Context Protocol) is a standard that lets AI assistants call external tools. Instead of giving the AI raw file contents, you can give it structured tools — "search for symbols matching X", "find all references to function Y", "get the dependency tree for this project."

I built CIPHER-Local, a VS Code extension that:

  1. Indexes your workspace using Tree-sitter (13 languages)
  2. Stores symbols, chunks, references, and dependencies in a local SQLite database
  3. Serves 7 MCP tools over HTTP+SSE on localhost

When your AI assistant needs code context, it calls these tools instead of scanning files blindly.

How it works in practice

Install the extension, open a project, and CIPHER-Local automatically:

  • Parses every supported file with Tree-sitter
  • Extracts functions, classes, interfaces, types, constants
  • Maps imports and call references
  • Indexes everything into SQLite with FTS5 full-text search
  • Starts an MCP server on a random localhost port
  • Auto-configures .github/copilot-instructions.md so Copilot knows to use MCP tools

Now when Copilot needs to understand your code, it can call search_symbols to find a function by name, resolve_symbol to get its definition, or find_references to see everywhere it's used. Structured data, not grep results.

What's supported

Languages: TypeScript, JavaScript, Python, Java, Go, Rust, C, C++, C#, Ruby, PHP, Swift, Kotlin

MCP tools:

  • search_symbols — find symbols by name pattern
  • resolve_symbol — get definition + source snippet
  • find_references — find import/call sites
  • semantic_search — BM25 full-text search
  • get_dependencies — package dependencies by ecosystem
  • get_file_context — all symbols for a file
  • list_namespaces — discover indexed workspaces

AI assistants: GitHub Copilot, Cursor, Claude Code, Claude Desktop — anything MCP-compatible.

Privacy: everything stays local

No cloud. No API keys. No account. The index lives in a SQLite file in your VS Code global storage. Nothing leaves your machine. MIT licensed.

Try it

Search "CIPHER-Local" in VS Code extensions or install from:
https://marketplace.visualstudio.com/items?itemName=Naman09Khater.ecip-local

This is a beta from a solo developer — I'd genuinely appreciate feedback on what languages to prioritize, what breaks, and what MCP tools would be most useful.

GitHub: https://github.com/Enterprise-Code-Intelligence-Platform/ecip-local

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