Spec Driven Development
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Runs on your computer
Toolcairn MCP
Overview
Description from the maker (original English)
MCP server for tool discovery: find, compare, and verify tools across 35+ registries.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
- UsageiVery new↓ 59/wk · ★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs on your computer
- Transport: stdio
- Category: Other
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 1 of 1 passed
- Runs on your computer with your user’s permissions (files, network, apps).
- The registry lists no key to fill in.
You need
- npmNode.js installed (for the npx command)
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json
{
"mcpServers": {
"toolcairn": {
"command": "npx",
"args": [
"-y",
"@neurynae/toolcairn-mcp"
]
}
}
}Run this in your terminal
claude mcp add toolcairn -- npx -y @neurynae/toolcairn-mcpOr copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"toolcairn": {
"command": "npx",
"args": [
"-y",
"@neurynae/toolcairn-mcp"
]
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Or copy the settings yourself
Paste into .vscode/mcp.json in your project
{
"servers": {
"toolcairn": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@neurynae/toolcairn-mcp"
]
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.
Your choice stays on this device in a cookie; no account needed.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
Runs on your computer; the tool list appears in your AI app after you install it.
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account neurynae, which owns the repo
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- – Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
- – Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
- … Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints
Compared with others in Otheri
- More stars than 0% of the other 18496 servers in this category
- Published to the registry more recently than 6% of the other 18496 servers in this category
- Basic checks equal to or better than 100% of the other 18496 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Toolcairn MCP safe?
It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
The registry does not list a required key, though some servers ask you to sign in on first use.
Does it run on my computer or in the cloud?
It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).
Is it still maintained?
The GitHub repo last changed –, and the latest version (1.0.0) reached the registry 6 months ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.
What can I use instead?
In the same category: Spec Driven Development, Remote Desktop Commander, MIDAS Gen NX / Civil NX
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:↓ Downloads per weeki★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Remote Desktop Commander
Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.
Runs in the cloud✓ desktopcommander.app
MIDAS Gen NX / Civil NX
Read and carefully change the model open in MIDAS Gen NX or Civil NX on this PC.
Runs on your computer
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
@neurynae/toolcairn-mcp
Source for
@neurynae/toolcairn-mcpon npm. Install via the package, not from this repo.
ToolCairn is an MCP server that connects your AI coding agent to a continuously-updated graph of 30,000+ open-source tools across npm, PyPI, Cargo, Maven, Go, Composer, RubyGems, NuGet, Homebrew, and 35+ more registries. Search, compare, build stacks, and check version compatibility — all from inside Claude Code, Cursor, or any MCP-compatible client.
Concrete example. Your agent receives *"I need a fast HTTP client for Node"* → it calls
search_tools→ ToolCairn returns ranked candidates with maintenance and community signals, alternatives, and a warning if the top pick has questionable activity. No more guessing from blog posts and stale tutorials.
The MCP server runs locally as a stdio child of your agent. Tool calls travel over MCP to this package, which proxies the network-bound ones to the ToolCairn Cloud API and handles the local-only ones (project scan, config, audit log) on disk.
Why ToolCairn?
Plain web search and LLM training data are insufficient for tool selection — knowledge cutoffs miss latest releases, search engines surface tutorials over authoritative ranking, and version-compatibility answers live in scattered issue threads.
ToolCairn fixes this with three things you can't get from raw registry APIs:
- Graph-aware ranking — recommendations consider how tools relate to each other (dependencies, integrations, replacements, conflicts), not just popularity.
- Version-aware compatibility — declared peer ranges and cross-registry version metadata give you *"Next.js 14 needs React 18.x"* instead of *"they're both popular, probably fine?"*
- A continuous learning loop — every accepted, rejected, or replaced recommendation feeds back into the graph, so quality improves with use.
Quick Start
Step 1. Create a free account at [toolcairn.neurynae.com/signup](https://toolcairn.neurynae.com/signup).
Step 2. Add to your MCP config and restart your agent:
{"mcpServers": { "toolcairn": { "command": "npx", "args": ["@neurynae/toolcairn-mcp"] } } }
Step 3. A browser window opens for sign-in on first start. Once you confirm, all tools are available immediately — no further setup.
Requires Node.js 22+.
Setup — Claude Code
The fastest path:
claude mcp add toolcairn -- npx @neurynae/toolcairn-mcpOr paste the JSON block above into ~/.claude/claude_desktop_config.json under mcpServers.
Other MCP-compatible clients (Cursor, Claude Desktop, VS Code Copilot, Windsurf, Zed, …) work with the same
npx @neurynae/toolcairn-mcpcommand — see the docs for client-specific config locations.
What you can do
Find a tool
Your agent receives *"I need a real-time analytics database for event tracking"* → calls search_tools → gets ranked candidates (ClickHouse, TimescaleDB, InfluxDB, …) with maintenance signals. If the intent is ambiguous, the response carries clarification questions; the agent answers via search_tools_respond and gets refined results.
Build a stack
Your agent receives *"Help me architect a full-stack TypeScript SaaS"* → calls refine_requirement to decompose, then get_stack with the per-layer needs → gets a 3–5 tool stack (web framework + database + auth + payments) with a version-compatibility matrix showing which versions work together across the stack.
Compare options
*"Express vs Fastify for a REST API?"* → compare_tools returns side-by-side health (stars, maintenance score, last commit, open issues, contributor trends), graph relationships (what each integrates with, what they replace), and a recommendation grounded in your stated use case.
Check version compatibility
*"I want to upgrade Next.js to 14 but keep React 17."* → check_compatibility evaluates declared peer ranges and returns satisfied/unsatisfied checks with the source (declared_dependency / graph_edges / shared_neighbors).
Track project tools
On first session, toolcairn_init walks your repo, parses every manifest (package.json, requirements.txt, pyproject.toml, Cargo.toml, go.mod, pom.xml, Gemfile, composer.json, …), classifies each tool against the ToolCairn graph, and writes a local .toolcairn/ snapshot. Subsequent sessions read this snapshot first — your agent stops re-searching for things it already knows about.
Available Tools
The MCP server exposes 16 tools, grouped by purpose. Most are local (no network) or fire-and-forget; the search, compare, and stack tools call the ToolCairn API.
Discovery
| Tool | What it does |
|---|---|
search_tools | Natural-language search with health signals and alternatives. May ask clarifying questions when intent is ambiguous. |
search_tools_respond | Submit answers to refine an in-progress search. |
refine_requirement | Decompose a vague use-case ("build a SaaS") into specific, searchable sub-needs. |
verify_suggestion | Check whether the agent's tool picks are actually indexed in the ToolCairn graph. |
Stacks & Compatibility
| Tool | What it does |
|---|---|
get_stack | Compose a complementary tool stack with a cross-version compatibility matrix. |
compare_tools | Head-to-head: health metrics, graph relationships, and a recommendation. |
check_compatibility | Version-aware peer-range check between two tools. |
Project Configuration
| Tool | What it does |
|---|---|
toolcairn_init | Discover project roots, scan manifests, classify tools, write .toolcairn/. |
read_project_config | Load the local .toolcairn/config.json snapshot (confirmed tools, pending items, audit log). |
update_project_config | Atomically add, remove, or update a tool — every mutation is audited. |
Feedback Loop
| Tool | What it does |
|---|---|
report_outcome | Fire-and-forget: did the recommended tool work out? Closes the learning loop. |
feedback | Agent feedback on ToolCairn itself. Call ONLY when a ToolCairn response was wrong, broken, low-quality, or missed something — never for positive feedback. Free of daily quota. |
suggest_graph_update | Submit a new tool, edge, or use-case for admin review (staged, never auto-promoted). |
check_issue | Last resort. Search a tool's GitHub issues for known bugs — only after 4+ retries and a docs review. |
Session
| Tool | What it does |
|---|---|
classify_prompt | Local: decide whether a tool search is needed at all (skips ToolCairn for non-tool prompts). |
toolcairn_auth | Manage local sign-in: login / status / logout. |
Configuration
| Environment variable | Default | Purpose |
|---|---|---|
TOOLCAIRN_TRACKING_ENABLED | true | Set false to disable usage event logging (see Privacy). |
LOG_LEVEL | info | Set debug for verbose stdio diagnostics. |
MCP_TRANSPORT | stdio | Set http for HTTP transport (advanced). |
Where things live
- Credentials →
~/.toolcairn/credentials.json(mode0600, 90-day expiry). - Per-project state →
.toolcairn/{config.json, audit-log.jsonl, tracker.html}at each detected project root.
The tracker.html file is a self-contained dashboard — open it in any browser to see every tool call, pending evaluation, and audit entry in real time.
Session management
Your sign-in lives at ~/.toolcairn/credentials.json and lasts 90 days. From inside your agent:
toolcairn_auth { action: "status" } # check current sign-intoolcairn_auth { action: "logout" } # clear credentials
To re-authenticate, simply restart your agent — the sign-in flow opens automatically.
Privacy & telemetry
We're explicit about what leaves your machine.
Sent to ToolCairn (when tracking is enabled):
- Tool name, duration, and success/error status — for service health and product analytics.
- Never full prompts, response bodies, or project file contents.
Stays local:
- Every audit entry (
.toolcairn/audit-log.jsonl). - Project state and tool snapshots.
- Your credentials file.
Opt out at any time:
TOOLCAIRN_TRACKING_ENABLED=falseTools still work normally; only the lightweight usage events are skipped.
Full privacy policy: toolcairn.neurynae.com/privacy.
Troubleshooting
Browser doesn't open for sign-in. Copy the URL printed to stderr and visit it manually; enter the device code shown.
`Module not found` or version errors. Confirm Node 22+ with node --version.
Behind a corporate proxy. Set HTTPS_PROXY — npx and the MCP server respect it.
Self-hosted backend. Set TOOLPILOT_API_URL=https://your-host.
Sign-in expired. Restart your agent — the device-code flow re-runs automatically.
Verbose logs. Set LOG_LEVEL=debug.
What is the agent doing? Open .toolcairn/tracker.html in your browser for an auto-refreshing dashboard of every tool call.
CLI: scan
A standalone health scan that doesn't start the MCP server:
npx @neurynae/toolcairn-mcp scan [dir]Reads dependency manifests in [dir] (default: current directory) — package.json, requirements.txt, pyproject.toml, Cargo.toml — and reports health, alternatives, and warnings for each declared dependency.
Add --json for machine-readable output.
Links
- Website: toolcairn.neurynae.com
- Docs: toolcairn.neurynae.com/docs
- npm: @neurynae/toolcairn-mcp
- GitHub: neurynae/toolcairn-mcp
- Issues: github.com/neurynae/toolcairn-mcp/issues
- Security: responsible disclosure to
security@neurynae.com
Contributing
Issues and feature requests are welcome at github.com/neurynae/toolcairn-mcp/issues.
The graph engine, search pipeline, and indexer are closed-source. This repository contains the public MCP client and project-config layer that runs on user machines.
License
MIT — © 2026 NEURYNAE. See [LICEN
Only the beginning is shown; read the rest in the repo