wiki-apis

name	wiki-apis
description	How to fetch live data from MediaWiki and Wikipedia — the two API surfaces (REST API for read-mostly endpoints, Action API for everything else), which to choose when, and the etiquette every consumer must follow (User-Agent, rate limits, anonymous vs authenticated, exponential backoff). Use when adding live Wikimedia data to a frontend, picking between REST and Action API, or debugging a 4xx / rate-limited response.
license	MIT

Wiki APIs

Wikipedia and the broader Wikimedia ecosystem expose two HTTP surfaces:

• REST API (/api/rest_v1/…) — clean, versioned, read-mostly. Great for "give me page HTML / summary / media list".
• Action API (/w/api.php) — older, action-based, can do everything including writes. Used for search, querying, parsing, login, and edit.

Use whichever expresses your need more cleanly. If both can do it, REST usually wins on shape and caching.

Picking the right surface

You want	Surface	Endpoint
Page HTML	REST	/api/rest_v1/page/html/{title}
Page summary (lead extract + thumbnail)	REST	/api/rest_v1/page/summary/{title}
Media in a page	REST	/api/rest_v1/page/media-list/{title}
Related articles	REST	/api/rest_v1/page/related/{title}
Page revision history	REST	/api/rest_v1/page/history/{title}
Page attribution signals	Core REST	/w/rest.php/attribution/v0-beta/pages/{title}/signals
Random page	REST	/api/rest_v1/page/random/summary
Featured / On-this-day	REST	/api/rest_v1/feed/featured/{date}
Pageviews	REST (Wikimedia metrics)	https://wikimedia.org/api/rest_v1/metrics/pageviews/…
Typeahead search	Action	?action=opensearch&search=…
Faceted query (categories, links, etc.)	Action	?action=query&prop=…
Rendered wikitext	Action	?action=parse
Login, edit, watch	Action	?action=login / edit / watch

Detailed call shapes:

• references/rest.md — Wikimedia REST (/api/rest_v1/). Same wiki hosts also serve MediaWiki Core REST under /w/rest.php/ (different routes and OpenAPI); see that page’s intro so you don’t confuse the two stacks.
• references/action.md
• references/schemas.md — pulling and storing the live API schemas (REST OpenAPI spec + Action API paraminfo) so agents and humans can look up endpoints offline.
• references/etiquette.md — non-optional reading.
• references/protowiki-integration.md — how this skill plugs into the ProtoWiki repo specifically (which components already wrap which endpoints, where the snapshot script lives, etc.).

URL conventions

https://en.wikipedia.org/api/rest_v1/page/html/Albert_Einstein
https://en.wikipedia.org/w/api.php?action=opensearch&search=alb&format=json&origin=*

For non-English wikis, swap the host:

https://de.wikipedia.org/api/rest_v1/page/summary/Albert_Einstein
https://fr.wikipedia.org/w/api.php?action=opensearch&search=alb&origin=*

For sister projects:

https://en.wiktionary.org/api/rest_v1/...
https://commons.wikimedia.org/w/api.php?...

The host already encodes the language, so a wrapping component typically only needs a host prop, not a separate lang.

CORS

Most public endpoints support CORS for browser fetches. For Action API calls, append &origin=* to opt into the public CORS handler:

fetch('https://en.wikipedia.org/w/api.php?action=opensearch&search=alb&format=json&origin=*')

REST API endpoints don't need origin=*.

Authentication

Prefer anonymous reads of public data. Don't ship credentials in client-side code. If you genuinely need authenticated reads or writes, that's a sign the work should be a server-rendered app, not a static SPA.

For short-lived demos that absolutely need a login, use OAuth 2 via MediaWiki's OAuth extension and proxy the token exchange through a trusted backend. Don't put a username/password in env vars or localStorage.

Etiquette — must read

The Wikimedia Foundation publishes a public API policy. Summarised:

• Send a descriptive User-Agent identifying your project + a contact (e.g., MyProject/0.1 (https://example.org/myproject; <email>)). Browsers send their own UA, but if you proxy a request server-side, set this. Anonymous, generic UAs may be rate-limited or blocked.
• Cache aggressively. REST API responses include strong ETag headers; Action API responses are CDN-cached at the edge. Don't poll faster than once per second per endpoint.
• Use exponential backoff on 429 (Too Many Requests) and 5xx errors.
• Use the read-only endpoints unless you mean to write. Don't edit unless your work is genuinely about editing.
• Don't load on every keystroke. Debounce typeahead requests; use AbortController to cancel superseded requests.

See references/etiquette.md for the full checklist.

Examples

Fetching article HTML

const res = await fetch(
  `https://en.wikipedia.org/api/rest_v1/page/html/${encodeURIComponent('Albert_Einstein')}`,
)
if (!res.ok) throw new Error(`HTTP ${res.status}`)
const html = await res.text()

Typeahead search

const url = new URL('https://en.wikipedia.org/w/api.php')
url.searchParams.set('action', 'opensearch')
url.searchParams.set('search', query)
url.searchParams.set('limit', '10')
url.searchParams.set('format', 'json')
url.searchParams.set('origin', '*')

const res = await fetch(url, { signal: abort.signal })
const [, titles, descriptions, links] = await res.json()

Pageviews

const url = `https://wikimedia.org/api/rest_v1/metrics/pageviews/per-article/en.wikipedia/all-access/all-agents/${encodeURIComponent('Albert_Einstein')}/daily/2024010100/2024013100`

Related articles

fetch(
  `https://en.wikipedia.org/api/rest_v1/page/related/${encodeURIComponent(title)}`,
)

Looking up endpoints offline

Both APIs publish machine-readable schemas:

• The REST API serves an OpenAPI 2 (Swagger) spec at https://<wiki-host>/api/rest_v1/?spec — each deployment has its own document (article wikis, wikimedia.org, Commons, Wikidata, …). The skill commits a small set of those JSON files side by side.
• The Action API serves module metadata via ?action=paraminfo&modules=*&format=json, plus ?action=help&recursivesubmodules=1 for the full prose docs.

This skill ships a small snapshotter (assets/fetch_schemas.sh) that writes several REST OpenAPI files plus Action paraminfo into assets/snapshots/ so an agent or human can read endpoint shapes without hitting the network. The committed snapshots serve as a reproducibility anchor — re-run the script when the upstream schemas change.

bash .agents/skills/wiki-apis/assets/fetch_schemas.sh
ls .agents/skills/wiki-apis/assets/snapshots/
# rest-api-spec.wikipedia.json   rest-api-spec.wikimedia-org.json
# rest-api-spec.commons.json     rest-api-spec.wikidata.json
# action-api-paraminfo.json

See references/schemas.md for the layout, the format of each file, and how to navigate them.

See also

• wiki-attribution — what attribution signals to show and how to fetch them (Attribution API beta, framework scenarios, levels).
• wiki-signals — what data is available (catalog of signals).
• wiki-snapshot-data — when to snapshot data ahead of time vs fetch live.

Inside ProtoWiki

ArticleLive calls REST page/html/{title}; Search wraps Action opensearch (with debouncing and AbortController cancellation). ArticleSnapshot loads public/snapshots/ HTML only (no page/html hit). Typical usage already covers UA etiquette and sane defaults.

Attribution API: Core REST under /w/rest.php/attribution/v0-beta/… (not /api/rest_v1/). CORS * — browser-fetchable. Use expand=trust_and_relevance,calls_to_action. See wiki-attribution and src/components/attribution/.

The committed schema snapshots live under .agents/skills/wiki-apis/assets/snapshots/ and are refreshed via fetch_schemas.sh. See references/protowiki-integration.md for the repo-specific UA, component pointers, and mock-publish guidance.