Getting started

Share by DeltaBreen is end-to-end encrypted: files and secrets are encrypted in the client with a key that lives only in the part of the link after the # (the fragment), and the server never receives a key, a link fragment or a password. The easiest way to use the API is the command-line tool or the MCP connector, which do the encryption for you. The raw HTTP endpoints below are for building your own client.

Not a developer? Start with a file request on your website, signature requests or the command line and your AI assistant. For code, the API examples are the quickest way in.

Base URL

All endpoints are under https://share.deltabreen.eu. Programmatic endpoints live under /api/v1.

Get a token

Signing in through OAuth (what the CLI and local assistants do) works on every plan, within that plan's limits. API keys, for servers and CI, and the online MCP connector need Studio and above. There are two kinds of credential:

API key

Create one in Settings, API keys and AI assistants. It looks like sbk_…. Send it as a bearer token:

curl https://share.deltabreen.eu/api/v1/whoami \
  -H "Authorization: Bearer sbk_your_key"

OAuth 2.1 (for assistants and installable apps)

Share by DeltaBreen is a full OAuth 2.1 authorization server with dynamic client registration and PKCE, so an AI assistant signs in through the browser and holds a rotating token, with no key to paste. Discovery documents:

GET/.well-known/oauth-authorization-server

GET/.well-known/oauth-protected-resource

Endpoints: POST /oauth/register, GET /oauth/authorize, POST /oauth/token, POST /oauth/revoke. Most people never call these directly: the CLI and the MCP connector drive them.

Scopes

A token carries some of these:

shares:read — list shares and read their activity
shares:write — create, complete and delete shares
secrets:write — create secrets that are deleted once opened
email:send — email a link to people
inbox:read — read what people send through file requests
inbox:write — create and manage file requests
usage:read — how much of your plan you have used
signatures:read — list signature requests and read who has signed
signatures:write — prepare and send signature requests, remind signers and cancel them
id_checks:read — see ID checks and where each stands
id_checks:write — make ID checks, send a new link and cancel them

Connect an AI assistant (MCP)

The online connector is a Streamable HTTP MCP server at https://share.deltabreen.eu/mcp (bearer auth over OAuth). For Claude Code: claude mcp add --transport http share https://share.deltabreen.eu/mcp. There is also a local stdio server (npx @deltabreen/share mcp) and a one-click Claude Desktop bundle. The Connect page has copy-paste setup for every client.

Errors and rate limits

Errors are JSON: { "error": "<stable code>", "message": "…" }. A plan limit returns 402 with a code you can map to the pricing page. API calls are rate-limited per key (Free 60, Pro 120, Studio 600, Business 3,000 requests a minute); a 429 means back off.