apipj
Brazilian company data by CNPJ from Receita Federal open data, incl. alphanumeric CNPJ; free tier

UK House of Commons MPs, parties and recorded votes.
Ayes and Noes API is a free Government API that requires no API key, is served over HTTPS and supports CORS, so it can be called from the browser.
Free UK Parliament API: JSON data for House of Commons MPs, parties, divisions (recorded votes) and Early Day Motions. Official open data, free to use. Light use needs no key; a free API key (just add a link back) lifts the daily limit. CORS-enabled.
Details from ayesandnoes.co.uk.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Brazilian company data by CNPJ from Receita Federal open data, incl. alphanumeric CNPJ; free tier
Official Spanish State Gazette open data: laws, summaries and XML/JSON APIs
The Ayes and Noes API is provided by Ayes and Noes (ayesandnoes.co.uk). Free UK Parliament API: JSON data for House of Commons MPs, parties, divisions (recorded votes) and Early Day Motions. Official open data, free to use. Light use needs no key; a free API key (just add a link back) lifts the daily limit. CORS-enabled.
Yes. The Ayes and Noes API is listed in the Government category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
No. The Ayes and Noes API requires no authentication, so you can start making requests without signing up.
Yes. The Ayes and Noes API supports CORS, so front-end JavaScript can call it directly.
Yes. The Ayes and Noes API is served over HTTPS, so it's safe to use in production.