About Gnomad
Gnomad is an MCP server for querying the Broad Institute’s gnomAD genomic database, suited to researchers and applications exploring genetic variation. It provides variant, gene, region, transcript, and autocomplete searches, with paged results for large variant lists.
Key features
- 01Look up variants by coordinates or rsid
- 02Retrieve variants near genes and transcripts
- 03Query genomic regions
- 04Search genes and variants
- 05Page through large variant lists
Use cases
- 01Review population allele frequencies for a variant
- 02Explore variants associated with a gene or transcript
- 03Inspect variants across a genomic interval
MCP support
Exposes gnomAD GraphQL-backed queries as MCP tools. Available as a local stdio server or through the Pipeworx gateway.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://gateway.pipeworx.io/gnomad/mcpclaude mcp add --transport http pipeworx-io-gnomad https://gateway.pipeworx.io/gnomad/mcp{"mcpServers":{"pipeworx-io-gnomad":{"type":"http","url":"https://gateway.pipeworx.io/gnomad/mcp"}}}Open in Cursor{"servers":{"pipeworx-io-gnomad":{"type":"http","url":"https://gateway.pipeworx.io/gnomad/mcp"}}}Open in VS Code{"mcpServers":{"pipeworx-io-gnomad":{"type":"http","url":"https://gateway.pipeworx.io/gnomad/mcp"}}}{"mcpServers":{"pipeworx-io-gnomad":{"serverUrl":"https://gateway.pipeworx.io/gnomad/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project README@pipeworx/gnomad
gnomAD MCP — Genome Aggregation Database (Broad Institute) public GraphQL endpoint. Population allele frequencies + variant pathogenicity annotations. Keyless.
Part of Pipeworx — an MCP gateway connecting AI agents to 1879+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.
Tools
variant(variant_id, dataset?)— bychr-pos-ref-alt(e.g.1-55051215-G-A) or rsidgene(gene_symbol_or_id, dataset?, limit?, offset?)— variants in / near a generegion(chrom, start, stop, assembly, dataset?, limit?, offset?)— variants in a genomic regiontranscript(transcript_id, dataset?, limit?, offset?)— variants in / near a transcriptsearch(query)— gene / variant search (autocomplete)
Variant lists are paged
gnomAD returns every variant for a gene, region or transcript with no limit of
its own (BRCA1 has about 7,300). gene, region and transcript return one
page — limit (default 500, max 2,000) starting at offset (default 0) — and
say so in the response:
truncated:truewhenever the page holds fewer variants than gnomAD has;variants_page:total(exact),returned,offset,limit,next_offset(nullon the last page),upstream_bytes, and a plainnote.
To get more, call again with offset = next_offset, raise limit, or narrow
the query with region. The page is cut while the response streams in, so a
large gene costs the gateway one page of memory, not the whole list.
dataset defaults to gnomad_r4 (most recent release). Other valid: gnomad_r3, gnomad_r2_1, gnomad_sv_r4, etc.
Data source
https://gnomad.broadinstitute.org/api
Quick Start
Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):
{
"mcpServers": {
"gnomad": {
"url": "https://gateway.pipeworx.io/gnomad/mcp"
}
}
}
What this endpoint actually serves
tools/list at https://gateway.pipeworx.io/gnomad/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 1879+ 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/gnomad_variant \
-H 'Content-Type: application/json' \
-d '{"variant_id":"1-55051215-G-A"}'
No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/gnomad_variant. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.
Standalone (no gateway account)
This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:
{
"mcpServers": {
"gnomad": {
"command": "npx",
"args": ["-y", "@pipeworx/mcp-gnomad"]
}
}
}
Or run it directly to confirm it starts:
npx -y @pipeworx/mcp-gnomad
It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call
for only this pack's tools — none of the shared meta-tools the gateway
connection above adds. Same source, same tools, no ask_pipeworx routing.
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 Gnomad data" })
The gateway picks the right tool and fills the arguments automatically.
More
License
MIT
Comments
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