devstack-mcp
A remote MCP (Model Context Protocol) connector for DevStack API — the libraries.io successor: one keyless, normalized view of the whole developer registry across npm, PyPI, Docker Hub, and the VS Code Marketplace (search, package details, versions, download/pull stats), plus resolved dependency graphs (deps.dev), per-version vulnerabilities (OSV.dev), OSSF Scorecard insights (deps.dev), and cross-registry lookups over 50+ ecosystems (ecosyste.ms).
Target deploy: https://devstack-mcp.vercel.app/mcp — 10 tools. Since the upstream DevStack deployment is metered (RapidAPI/Apify) and gates /v1/* behind a RapidAPI proxy-secret guard, this connector authenticates its own outbound calls with that same proxy secret (DEVSTACK_MCP_PROXY_SECRET, sent as the X-RapidAPI-Proxy-Secret header) and applies a soft per-IP rate limit (DEVSTACK_MCP_RATE_LIMIT, default 30 tool-calls/hour, in-memory) so the free MCP tier stays a discovery channel rather than an unmetered bypass of the paid listing — see lib/ratelimit.js.
What this is, and why it's a separate connector
DevStack API is a plain REST API. Any HTTP client can already call it directly. This repo exists because MCP clients (Claude, ChatGPT, and other MCP-aware agents) don't consume arbitrary REST APIs — they consume MCP tools. devstack-mcp is a thin adapter layer that:
- Exposes each DevStack endpoint as a discoverable, typed MCP tool (name, description, zod input schema, annotations) that an LLM can reason about and call directly, instead of having to be taught the REST surface out-of-band.
- Speaks the MCP streamable-HTTP transport at a single
/mcp endpoint, so it can be registered as a connector in Claude, ChatGPT, or any other MCP client with one URL.
- Does nothing else. It has no business logic of its own — every tool call is a pass-through
fetch to DevStack, and the JSON response DevStack returns is handed back verbatim as the tool result.
Authentication: None on the MCP side (deliberate)
DevStack's data has no per-user dimension at all — it's public developer-registry metadata (package listings, versions, download counts, dependency graphs, published CVEs). There is nothing to gate per-caller, so this connector intentionally ships with:
- No OAuth, no login, no per-user bearer tokens
- No Supabase / database
- No demo-vs-real account split — every caller gets the same real, live data
The one server-side secret it carries (DEVSTACK_MCP_PROXY_SECRET) is not per-caller auth — it's how this connector, as a single consumer, gets past the upstream's RapidAPI proxy-secret guard to reach real data. Combined with the soft per-IP rate limit, that keeps this a free discovery tier over the metered DevStack product rather than an unmetered bypass of the paid RapidAPI/Apify listing.
One tool per DevStack /v1 endpoint (from devstack-api/openapi.yaml):
| Tool | DevStack endpoint | Description |
|---|
get_package | GET /v1/package | Normalized package details by registry + name (registry=all fans out). |
search_packages | GET /v1/search | Search npm/Docker/VS Code (or all); PyPI has no search API. |
get_versions | GET /v1/versions | Published versions / image tags / extension versions. |
get_downloads | GET /v1/downloads | Download / pull statistics (npm + PyPI only). |
get_dependency_graph | GET /v1/deps | Fully resolved dependency graph for one exact version (deps.dev). |
get_vulnerabilities | GET /v1/vulns | Known CVEs/GHSAs per package/version (OSV.dev). |
scan_vulnerabilities_batch | POST /v1/vulns | Batch/lockfile vulnerability scan — up to 100 queries in one call (OSV.dev). |
get_insights | GET /v1/insights | OSSF Scorecard + repo signal + licenses/advisories (deps.dev). |
search_ecosystems | GET /v1/ecosystems/search | Cross-registry exact-name lookup across 50+ ecosystems (ecosyste.ms). |
get_ecosystems_package | GET /v1/ecosystems/package | One package on one registry, with reverse-dependency counts (ecosyste.ms). |
All 10 tools are read-only and annotated { readOnlyHint: true, destructiveHint: false, idempotentHint: true, openWorldHint: true }. scan_vulnerabilities_batch is an HTTP POST but is a read-only query (it mutates nothing), so it carries the same read-only annotations.
How it wraps devstack-api
Each tool handler does a plain fetch(\${DEVSTACK_MCP_API_BASE_URL}${path}`, ...)` against the real DevStack REST API and returns the parsed JSON as MCP tool-result content:
{ content: [{ type: 'text', text: JSON.stringify(result, null, 2) }] }
Upstream HTTP errors (4xx/5xx) are caught and surfaced as a typed MCP error result via an asError helper rather than crashing the request.
Environment variables
| Env var | Purpose | Default |
|---|
DEVSTACK_MCP_API_BASE_URL | Upstream DevStack base URL. | https://devstack-api.vercel.app |
DEVSTACK_MCP_PROXY_SECRET | RapidAPI proxy secret, sent as X-RapidAPI-Proxy-Secret to pass the upstream /v1/* guard. | "" (omitted) |
DEVSTACK_MCP_RATE_LIMIT | Soft per-IP tool-calls/hour cap for this free tier. | 30 |
Project layout
api/mcp.js MCP endpoint (StreamableHTTPServerTransport, stateless, no per-caller auth)
api/health.js GET /api/health
lib/tools.js All 10 tool definitions (zod schemas + fetch-and-forward handlers)
lib/ratelimit.js Soft per-IP tools/call cap (free discovery tier)
local-server.js Plain-Node http server for local dev / smoke testing (not deployed)
test/smoke.mjs Real end-to-end smoke test (initialize, tools/list, tools/call)
vercel.json Routes /mcp -> api/mcp.js, /health -> api/health.js
server.json MCP registry publish manifest
Local development
Endpoints locally: POST http://localhost:3900/mcp, GET http://localhost:3900/health.
To point at a self-hosted / open DevStack instance instead of production (useful for a fully keyless end-to-end run, since production's /v1/* is behind the RapidAPI proxy-secret guard):
node server.js
DEVSTACK_MCP_API_BASE_URL=http://localhost:8080 npm run dev
Smoke test
npm run dev &
npm run smoke
test/smoke.mjs drives the running server over real HTTP/JSON-RPC and verifies:
GET /health returns { ok: true, ... }initialize succeeds and reports serverInfo.name === "devstack"tools/list returns all 10 tools with their zod-derived JSON schemastools/call for get_package with { registry: "npm", name: "react" } returns real package data fetched live (not mocked)
Against production, step 4 needs DEVSTACK_MCP_PROXY_SECRET set (the RapidAPI proxy guard); against a locally self-hosted devstack-api with no RAPIDAPI_PROXY_SECRET, the guard is inert and real data flows keyless.
Deploy
Not deployed by this build. Once ready:
cd /Users/isaiahdupree/Software/devstack-mcp
npx vercel --yes --prod
After deploy, set DEVSTACK_MCP_PROXY_SECRET in the Vercel project so the connector can reach the guarded production /v1/*, then register the MCP connector URL in Claude/ChatGPT/any MCP client:
https://<deployment-domain>/mcp