
Isrctn
io.github.pipeworx-iov0.1.0Updated Oct 10, 2026
ISRCTN — the UK-based international clinical trial registry
Overview
Lets an assistant search the ISRCTN clinical trial registry and retrieve full structured records for UK and international trials.
- What it does
- Provides two tools over the ISRCTN public XML query API: isrctn_search, which accepts free-text query terms or specific condition and intervention fields, and isrctn_trial, which returns a single trial's full record including title, conditions, interventions and phase, sponsor, funder, dates, countries, and whether a results report has been posted. Search results include a derived status computed from recruitment and end dates, since the registry feed carries no status field. Condition and intervention filters are combined with AND, and the response echoes what was searched.
- When to use it
- Useful when a question about clinical trials needs international coverage, especially UK or EU sponsored studies that may not appear on ClinicalTrials.gov. The README suggests pairing it with a ClinicalTrials.gov source rather than replacing it.
- Requirements
- No account, API key, or environment variable is needed. It runs as a remote streamable HTTP endpoint, or locally via npx as a stdio server. Network access to the ISRCTN API is required.
Installation
In SourceWeft
- Open Isrctn in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.
Other MCP clients
Add this to your client's mcpServers config.
{
"mcpServers": {
"isrctn": {
"type": "http",
"url": "https://gateway.pipeworx.io/isrctn/mcp"
}
}
}README
ISRCTN — UK-Based International Clinical Trial Registry
ISRCTN (isrctn.com) is a primary clinical trial registry recognised by WHO and ICMJE, operated by Springer Nature/BMC. It covers UK and international trials — including many non-US studies that never appear on ClinicalTrials.gov — and assigns a permanent ISRCTN number to every registered study. Free, keyless, public XML query API.
Part of Pipeworx — an MCP gateway connecting AI agents to 1763+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.
Why this matters for AI agents
ClinicalTrials.gov is US-centric. A question like "what trials exist on
psilocybin for stroke recovery" is only half-answered without ISRCTN, since
several UK/EU-sponsored studies register here instead of (or in addition to)
ClinicalTrials.gov. Use this pack alongside clinicaltrials for international
coverage, not in place of it.
Two flows:
1. Search. "Studies on X and Y" → isrctn_search({query: "psilocybin depression"})
or, to require BOTH a registered condition and a registered intervention,
isrctn_search({condition: "stroke", intervention: "psilocybin"}). Combining
condition and intervention is an AND, not an OR — a real zero means no
ISRCTN trial currently pairs that condition with that intervention, and the
response echoes query_used so the caller can see exactly what was searched.
2. Single record. isrctn_trial({id: "ISRCTN37167117"}) → full structured
record: title, condition(s), intervention(s)/phase, sponsor, funder, dates,
countries, and whether a results report has been posted.
Status is DERIVED, not a registry field
ISRCTN's XML feed carries no "overall trial status" string — unlike
ClinicalTrials.gov. Every returned trial computes status from its
recruitment-window dates (recruitment_start, recruitment_end,
overall_end_date) relative to the current date, and status_basis names
exactly which date drove the call (e.g. "overall trial end date
(2025-01-23T00:00:00.000Z) has passed"). isrctn_search's status filter
matches against this derived value and is applied client-side over a
fetched batch (status_filter_scanned reports how many trials were scanned),
since the upstream has no server-side status field to filter on.
Search syntax
query is free text (ISRCTN's search is a Lucene index over the full record
— title, summary, eligibility criteria, etc.). Multiple words are ANDed by
default ("psilocybin depression" matches trials containing both terms, not
either), confirmed against the live API: psilocybin depression and
psilocybin AND depression return identical counts, "psilocybin depression"
(a phrase) returns zero. condition and intervention match ISRCTN's
indexed condition: / intervention: fields specifically — these are
narrower than a free-text match on the same word (e.g. condition:stroke
returns ~1/4 the hits of a bare stroke search, because it excludes trials
that only mention "stroke" in eligibility criteria or elsewhere).
At least one of query, condition, intervention is required.
Auth
Keyless. Public, unauthenticated XML query API.
Data sources
https://www.isrctn.com/api/query/format/default?q={lucene_query}&limit={n}— search (e.g.q=psilocybin+depression&limit=10); also used for single-record lookup (isrctn_trialqueries by the canonicalISRCTN37167117-shaped id withlimit=1).
Notes for the next person
- The single-record URL shape
/api/query/ISRCTN37167117/format/defaultdocumented informally elsewhere 404s live (verified 2026-10-09) — the working path for one record is the SAME search endpoint, queried by id. - A non-existent ISRCTN id returns
HTTP 200with an emptyallTrialselement (totalCountof zero) — a legitimate empty result, surfaced as{found: false}, not an error. - A malformed Lucene query (e.g. unbalanced quotes) also silently returns
totalCount="0"rather than an HTTP error — user input going intoquery,condition, andinterventionis Lucene-escaped before being sent, so a caller's literal text (parentheses, colons, quotes) can't accidentally produce a false zero from broken query syntax. - A response that is HTTP 200 but has no
allTrials/totalCountroot element, or that claimstotalCount > 0with zero parseable fullTrial blocks, is thrown as a loudupstream_parseerror — never silently returned as an empty result.
Quick Start
Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):
What this endpoint actually serves
tools/list at https://gateway.pipeworx.io/isrctn/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:
Both URLs reach the same gateway and the same 1763+ 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
No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/isrctn_search. 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:
Or run it directly to confirm it starts:
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:
The gateway picks the right tool and fills the arguments automatically.
More
License
MIT
Source: README.md at commit 7554f35
Tools
0Version history
1- v0.1.0LatestOct 10, 2026