Codelens Mcp

io.github.segentic-labPublished by GitHub account segentic-labv0.2.0Updated Oct 24, 2026

Deterministic code maps for AI agents: 7 tree-sitter tools for TS/JS/Py — map, find, function_body

VerifiedSTDIODesktop onlyKnowledge & MemoryDeveloper Tools

Overview

AI-generated overview

A local stdio MCP server that gives assistants deterministic structural maps of TypeScript, JavaScript and Python code, so they can locate code without reading

What you can do
Map a whole directory tree's per-file structure in one call, skipping node_modules, dist and hidden folders.Outline a single file's imports, exports, classes and functions with line ranges.List every addressable function with signatures, types and parent scope, and read one function's verbatim source by name.Find where a function, method or class is defined across a directory, and list comments with TODO/FIXME-style markers.Report the server's version, sandbox root, supported languages and caps.
When to use it
Useful when an assistant works in a TypeScript, JavaScript or Python project and needs to orient itself, locate definitions or pull a single function body instead of reading whole files into context. Note the README says the project is superseded by a successor server and is no longer developed.
Requirements
A local Node.js 18+ runtime; the README's install steps build from source with npm and run the compiled entry point over stdio. Launch it from the project directory to be analyzed, since it only reads files under its working directory. No accounts, keys or environment variables are declared.
Before you install
Read-only tools, but the path sandbox limits access to the launch directory, so start it from the right project. The README marks the project as superseded and no longer developed, pointing to a successor server; check that before adopting it. Syntax errors are flagged rather than silently ignored.

Installation

In SourceWeft

  1. Open Codelens Mcp in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

codelens-mcp

⚠️ Superseded by lens-mcp

codelens has merged into lens-mcp — one MCP server that maps both code and markdown docs. It carries every codelens tool (map, overview, functions, function_body, comments, find, info) unchanged, plus doc tools (outline, heading, links, search) and a unified map that returns a whole project's code structure and doc outlines in one call.

Use lens-mcp instead — git clone https://github.com/segentic-lab/lens-mcp. This repo remains only so existing links resolve; it is no longer developed.

(The description below is retained for reference.)

Deterministic structural code maps for AI agents. An MCP server (stdio) that gives agents the shape of a codebase — imports, exports, classes, functions, signatures, comments, TODO-markers — without reading whole files into context. Powered by tree-sitter WASM grammars: no native build step, installs anywhere Node 18+ runs.

The contract: codelens is a navigation map. Use it to locate code, then Read the actual source before judging or modifying it. A signature is not the body; an outline is not the section.

Tools

7 read-only tools. Every list in every response is capped, and every cap is reported with an explicit truncated flag — no silent cutoffs.

ToolWhat it does
mapPer-file structural overview of a whole directory tree in one call. Skips node_modules, dist, venv, hidden dirs, etc. The orientation tool.
overviewOne file's top-level structure: imports, exports, classes (with method names), functions — all with 1-based line/endLine.
functionsEvery addressable function in a file — nested functions, methods, getters/setters, class-field arrows, object-literal properties, default exports — with reconstructed signatures, param types, return type, async/exported flags, and parent scope. (Anonymous callbacks passed as arguments and Python lambdas are not listed — they have no name to navigate to.)
commentsAll comments with line ranges, kind (line/block/doc), and TODO/FIXME/FIX/BUG/HACK/NOTE/XXX marker detection (uppercase-only, no prose false-positives). markersOnly: true returns just the debt list.
function_bodyVerbatim source of one function (with decorators) by bare or dotted name (Widget.render) — the focused read that replaces whole-file Reads. Ambiguous names fail listing the candidates; it never guesses.
find"Where is X defined?" — locate function/method/class definitions by name across a directory. Definitions only, not call sites.
infoServer self-description: version, working directory (the path sandbox root), languages, caps.

overview, functions, and comments accept a single path or an array of up to 20 paths per call.

Languages

ExtensionLanguageGrammar
.ts, .mts, .ctsTypeScripttree-sitter-typescript
.tsxTypeScript + JSXtree-sitter-tsx (dedicated grammar — JSX parses correctly)
.js, .jsx, .mjs, .cjsJavaScripttree-sitter-javascript
.pyPythontree-sitter-python

Path sandbox

The server only reads files under its own working directory (the directory it was launched from). Relative paths resolve against it; absolute paths are accepted only if they point inside it; symlinks that escape it are rejected. The info tool reports the root, and every rejection names it. Launch the server from the project you want mapped.

Honesty guarantees

  • A file with syntax errors is never reported as a clean success: hasErrors: true plus parseErrors line ranges, because tree-sitter error-recovery can drop code near the error.
  • Errors set isError on the MCP result and return {error, path, hint} — the hint says how to fix the call.
  • Batch calls return per-file results plus an honest {requested, succeeded, failed} summary; isError only when every file failed.
  • Every cap is visible: truncated flags carry the true totals.

Install & run

bash
npm installnpm run build    # tsc → dist/npm test         # build + 62 tests (51 unit, 11 stdio e2e)node dist/index.js   # stdio MCP server (launch from the project to analyze)

MCP client config:

json
{  "mcpServers": {    "codelens": {      "command": "node",      "args": ["/path/to/codelens-mcp/dist/index.js"],      "cwd": "/path/to/project-to-analyze"    }  }}

For agent authors

AGENTS.md in this repo is a paste-ready guide for teaching an agent to use these tools well — core model, per-tool tips, and the pitfalls (path sandbox, language coverage, the map-vs-territory rule).

License

AGPL-3.0 — see LICENSE.

Source: README.md at commit 9c05ee5

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.2.0LatestSep 16, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

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  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts