Nih Supplements MCP Server

@pipeworx/nih-supplements

NIH fact sheets for vitamins, minerals and a few botanicals — uses, safety, interactions with medications, references — plus real supplement product labels from NIH's Dietary Supplement Label Database, and NCCIH's herb safety/science summaries for the many popular herbs ODS itself doesn't cover.

Part of Pipeworx — an MCP gateway connecting AI agents to 1856+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

• supplement_factsheet(name, level?) — a topic's ODS fact sheet: what it does, whether it works, safety, and interactions with medications. level is consumer (short, default) or professional (long, clinical, with a references list).
• supplement_factsheets(query?) — the bundled list of ~45 topics ODS publishes a fact sheet for, and which reading levels each has.
• supplement_labels(query, limit?) — search real product labels (brand, ingredients, amounts, claims) from the Dietary Supplement Label Database (DSLD) by product, brand, or ingredient.
• supplement_label(id) — one product's full label detail: ingredient amounts, other ingredients, manufacturer contact, precaution statements.
• herb_at_a_glance(herb) — NCCIH's "Herbs at a Glance" science-and-safety summary for ~56 popular herbs (turmeric, ginkgo, echinacea, garlic, ginseng, milk thistle, St. John's Wort, and more) that ODS does not have its own fact sheet for.
• supplement_recent_changes(since, limit?) — new DSLD product labels entered on or after a date, newest first, deterministic on replay. DSLD is the only NIH supplement upstream with a queryable change signal; the response states plainly that withdrawals (offMarket transitions) and ODS/NCCIH content updates are NOT diffable upstream rather than pretending to cover them.

Change tracking & enumeration (for periodic refreshers)

• New labels: supplement_recent_changes(since) pages DSLD newest-first (sort_by=entryDate&sort_order=desc) to the cutoff — deterministic, so replays are idempotent until NIH enters new labels.
• Fact-sheet / herb-page content changes: not diffable upstream — no list endpoint, no sitemap lastmod (checked 2026-09-08; NCCIH's sitemap exists but carries no dates, and HHS's syndication API is bot-walled). Each supplement_factsheet response carries its own reviewed date.
• Full enumeration: both content corpora are bundled and small — supplement_factsheets() lists all ~45 ODS topics; the ~56 NCCIH herbs are in NCCIH_HERBS in src/index.ts (and any name from either list can be fetched in full). DSLD's full corpus (~215k labels) is enumerable via the same sorted paging (size/from), and NIH also publishes full DSLD dataset downloads at https://dsld.od.nih.gov/ for bulk use. There is no versioned bulk file for the fact sheets — enumeration over the bundled inventory IS the snapshot path for them.

Auth

Keyless. All three upstreams (ODS fact sheets, DSLD, NCCIH) are open NIH sites with no API key.

Data sources

• https://ods.od.nih.gov/api/ — ODS fact sheet XML API (?resourcename=<slug>&readinglevel=Consumer|HealthProfessional&outputformat=XML). Trap: a fresh call from a browser-shaped User-Agent returns real XML; a rapid second call from the same client comes back HTTP 200 with an HTML bot-check page instead of data — same status code, no error, completely different body. Never trust an HTML-shaped 200 from this host as a "not found"; it means "slow down and retry". This pack handles it with a per-isolate cache plus a floor between outbound calls (spacedFetch/MIN_GAP_MS in src/index.ts) — don't remove that if you touch this file.
• https://ods.od.nih.gov/factsheets/list-all/ — there is no live endpoint that lists every fact sheet (the obvious one 403s; the sitemap carries no fact-sheet URLs), so the ~45-topic inventory (ODS_TOPICS in src/index.ts) is bundled by hand from this page, read once on 2026-09-07. Almost every topic uses the same slug for both reading levels — level is a separate query param — except two: "Dietary Supplements in the Time of COVID-19" and Chromium each use a different slug per level, which is why the inventory stores consumerSlug/professionalSlug per topic instead of one shared slug.
• https://api.ods.od.nih.gov/dsld/v9/search-filter?q= — DSLD label search, keyless JSON. hit._source carries brandName, fullName, productType, allIngredients, claims, netContents, offMarket.
• <https://api.ods.od.nih.gov/dsld/v9/label/> — DSLD label detail (not documented anywhere findable; discovered by pattern-matching the search API's _id field on 2026-09-07). Carries ingredient amounts (ingredientRows[].quantity[]), other ingredients, manufacturer contact, and the precaution/warning statements printed on the bottle.
• <https://www.nccih.nih.gov/health/> — NCCIH "Herbs at a Glance" pages. No JSON-LD, __NEXT_DATA__, or XHR/API was found (checked 2026-09-07), but every page's content <h2> carries a stable id attribute — background, how-much-do-we-know, what-have-we-learned, what-do-we-know-about-safety, keep-in-mind, for-more-information, key-references — verified identical and in the same order across 5 herbs (ashwagandha, echinacea, garlic, ginkgo, turmeric). That is the "sections are stable" condition required before building a bounded prose extractor over these pages (docs/herbal-sources-scope.md §2); it passed, so herb_at_a_glance ships. The ~56-herb list (NCCIH_HERBS) is likewise bundled by hand from nccih.nih.gov/health/herbsataglance, read once on 2026-09-07 — there is no live index for this either.
• German Commission E (the ABC English translation on herbalgram.org) is not ingested — it's a copyrighted 1998/2000 work with no reuse terms on the page. If you need it, link the URL; don't scrape or mirror the text.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "nih-supplements": {
      "url": "https://gateway.pipeworx.io/nih-supplements/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/nih-supplements/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1856+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/supplement_factsheet \
  -H 'Content-Type: application/json' \
  -d '{"name":"Ashwagandha","level":"consumer"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/supplement_factsheet. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Run it from npm

@pipeworx/mcp-nih-supplements is a local stdio bridge to the Pipeworx gateway: your MCP client starts it with npx, and it forwards every call to the same https://gateway.pipeworx.io/nih-supplements/mcp endpoint shown above. It needs network access; there is no offline mode.

{
  "mcpServers": {
    "nih-supplements": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-nih-supplements"]
    }
  }
}

Without a key it calls anonymously, capped at 50 calls a day. A free account raises that to 200 a day: get a key at https://pipeworx.io/signup and add "env": { "PIPEWORX_API_KEY": "<your key>" } to the server entry. The key is sent as a Bearer token, the same way a hosted connection sends it, so calls are metered and billed exactly as they are there.

It lists only this pack's tools by default. Set PIPEWORX_META_TOOLS=1 to also list ask_pipeworx and the other gateway-wide tools.

Behind an HTTPS proxy: Node's built-in fetch does not read HTTPS_PROXY by default. Newer Node releases honour it when NODE_USE_ENV_PROXY=1 is set; check your Node version's documentation.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Nih Supplements data" })

The gateway picks the right tool and fills the arguments automatically.

More

• Docs and guides
• pipeworx.io

License

MIT