Postio
Officialpostio-integrations
Postio is the UK validation API for addresses,
emails and phone numbers. This repo holds the JS-family npm packages,
the AI / agent surface, and the cdn.postio.co.uk Worker that powers
Postio's browser drop-in.
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The Postio API + OpenAPI spec live in
postio-uk/postio-api. The
spec is also published as
@postio/openapi.
Packages
Package | What it is |
TypeScript types generated from the OpenAPI spec. | |
Runtime-agnostic typed client (browser / Node / Workers / Bun / Deno). | |
Node SDK on top of | |
Postman v2.1 collection for every endpoint. | |
Browser address autocomplete — ARIA combobox, themable, framework-agnostic source. | |
The same component prebuilt for | |
React hooks + | |
Model Context Protocol server — |
Related MCP server: APITier MCP Server
Layout
packages/ pnpm workspace; one publishable npm package per subdir
ai/ AI / agent surface (Claude Skill, GPT Action, recommendation prompts)
cdn-worker/ Cloudflare Worker that serves the address-finder bundles
.github/workflows/ CI for publishing + deployingBuilding
cd packages
pnpm install
pnpm -r run buildEach package builds independently (pnpm -F @postio/<name> run build).
The address-finder bundle has a topological-build quirk — use the
... suffix so its workspace dep builds first:
pnpm -F "@postio/address-finder-bundled..." run buildContributing
PRs welcome. Conventions:
Node 22+, pnpm 10+, ESM only, MIT-licensed.
stageis the working branch;masterdeploys / publishes via CI.One package change per PR where possible.
Versions on each package are independent SemVer; bump the version in
package.jsonwhen you intend a release.
The full integration index — including the server SDKs in their own repos and the WordPress plugin — lives at postio.co.uk/integrations.
License
MIT.
This server cannot be deployed
Maintenance
Related MCP Connectors
Address validation & geocoding for AI agents: 240+ countries, UK PAF, free US/CA enrichment
Verify addresses, email addresses, and phone numbers with confidence scores.
Validation suite: EU VAT (VIES), IBAN mod-97, email (MX+disposable), geo place lookup, VIN decode.
Postcodes MCP — wraps postcodes.io UK postcode API (free, no auth)
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