parameterised-query

name	parameterised-query
description	Use the UK Parliament parameterised query browser (api.parliament.uk/query/) — a catalogue of pre-canned SPARQL queries that return JSON without you having to write the SPARQL yourself. Each template has a fixed name and a fixed parameter signature, e.g. person_by_id?person_id=… or constituency_lookup_by_postcode?postcode=…. Use when you want a specific, pre-vetted answer about a Parliament resource and do not want to author SPARQL.
license	Open Parliament Licence v3.0 (Crown copyright; Parliament-operated)
metadata	{"provenance":{"tier":1,"operator":"UK Parliament","service":"api.parliament.uk/query","citation-short":"via api.parliament.uk/query","citation-formal":"UK Parliament parameterised-query browser, retrieved {date}","confidence":"authoritative"}}

UK Parliament parameterised query browser

Endpoint: https://api.parliament.uk/query/

This is the public face of an internal Parliament service that wraps common SPARQL questions as named, parameterised templates. It is read-only and HTTP-GET-only. The root path returns a list of every template; calling a template with the right query-string parameters runs the underlying query and returns JSON (or HTML in the browser).

What it covers

124 named templates as of 2026-04-30 (see _specs/discovered/query-templates.txt).

Examples (the full list is the file above):

• person_index — every person URI in the store.
• person_by_id?person_id=TyNGhslR
• person_by_initial?initial=A
• person_by_substring?substring=ee
• person_lookup?property=mnisId&value=3299
• person_constituencies?person_id=TyNGhslR
• person_current_constituency?person_id=TyNGhslR
• person_committees_memberships_index?person_id=TyNGhslR
• person_mps
• member_current
• constituency_lookup?property=onsCode&value=E14000699
• constituency_lookup_by_postcode?postcode=SW1P%203JA
• constituency_current_member?constituency_id=AEyWGYaP
• find_your_constituency — useful pre-canned postcode → MP lookup.
• party_index

Common entry points

Use case	Template
Postcode → constituency → current MP	constituency_lookup_by_postcode?postcode=...
ONS code → constituency	constituency_lookup?property=onsCode&value=E14000699
MNIS ID → person URI	person_lookup?property=mnisId&value=3299
All current MPs	person_mps or member_current
Person → committees they have been on	person_committees_memberships_index?person_id=...

Worked example

curl -s 'https://api.parliament.uk/query/constituency_lookup_by_postcode?postcode=SW1P%203JA' \
  | jq '.[0]'

Relationship to the sparql skill

api.parliament.uk/query is a named-query layer over the same DDP store that api.parliament.uk/sparql exposes directly. Same graph, same URIs, same coverage:

• Anything the templates can answer, you can also answer in SPARQL.
• Anything the SPARQL endpoint can't answer (Bills, Hansard contributions, divisions, RMFI, elections, EDMs, Erskine May, APPGs — see sparql/SKILL.md) the templates also can't, because the underlying data isn't there.

Pick this skill when there's a named template that fits the question; drop down to sparql for arbitrary joins, schema discovery, classes outside the templated set, or any of the ~194 classes in the parl: schema that don't have a pre-canned template.

The IDs are the same opaque 8-character id.parliament.uk shortIds as in the SPARQL store and as in some REST APIs (treaties, e-petitions), so results from one skill compose directly with the others.

Notes

• Each template returns JSON when called with the standard Accept: default. The HTML browser lets you click through to inspect.
• Templates are stable but the canonical record of the set is the service itself; we cache the list under _specs/discovered/query-templates.txt and a re-fetch is captured by scripts/probe-endpoints.sh (extension TODO — currently we only record the count and the root URL).

Using the CLI

See ../parl/SKILL.md for the CLI-wide conventions (output modes, flag rules, idiomatic chains).

This skill ships with a Node CLI alongside the documentation. From the repo root:

node bin/parl.mjs pq --help

Or after npm link (one-time install):

parl pq --help

Wraps the parameterised-query browser. 124 named templates returning JSON; covers the most common joins without writing SPARQL.

Examples

parl pq postcode "SW1P 3JA"

Postcode → constituency → current MP.

parl pq mps

All current MPs.

parl pq person-by-mnis 4514

Person by MNIS ID.

parl pq run constituency_lookup --property=onsCode --value=E14000647

Arbitrary template invocation.

Library use (Node + browser)

Same surface as a JS module:

import * as fac from '../../lib/facilities/parameterised-query.mjs';

// Each function is async and returns parsed JSON (or bytes for
// download endpoints). See the .mjs source for the full export list.

The library uses only fetch / URL / AbortController, so the same source runs in Node 18+ and in modern browsers.

Provenance to cite

Tier 1 — first-party UK Parliament. Authoritative.

• Inline cite: "(via api.parliament.uk/query)" — once per paragraph in user-facing answers.
• On request, give the URL --raw printed.
• See docs/provenance.md for the cross-skill rules.