SDK overview

This directory organizes code and docs by four ways to extend Cadau. If you are unsure which to pick, start with the table, then open the matching subdirectory.

Source docs/en/site/sdk-overview.md

This directory organizes code and docs by four ways to extend Cadau. If you are unsure which to pick, start with the table, then open the matching subdirectory.

Directory	In user language	Typical case	Code	Doc entry
`host-embed/`	Host embed	Hang an embed assistant on an existing business system	`host-embed/widget/`	Handover docs you can ship as a pack
`platform-plugin/`	Plugin apps	Full web in an apps-desktop iframe	`go/` · `js/` · `contracts/` · `templates/`	Platform plugin mechanism and API
`agent-capability/`	Agent capabilities	Call a business API from Messages	Planned	Skills + internet capability pack
`appsdk/`	Workspace apps	Lightweight `app.json` apps inside a workspace	`backend/internal/workspaceapp/`	UI / handlers / data-fetch specs

The widget script URL in the browser is still /embed/mindlink-widget.min.js (HTTP route; independent of this folder name).

Decision tree

Is the user's main UI still the existing business system (legacy host)?
    ├─ Yes → host-embed (embed assistant + host actions)
    └─ No → Need a full web module on the apps desktop?
          ├─ Yes → platform-plugin (platform_plugins + mindlink-plugin*)
          └─ No → Only call APIs / skills from Messages?
                ├─ Yes → agent-capability (skills + http_request)
                └─ No → Lightweight app in the workspace? → appsdk

What each directory contains

host-embed (host embed)

Docs: [host-embed/README.md](/docs/sdk-host-embed) — contract, website integration, host knowledge, HR example, host LLM service
Widget source: host-embed/widget/ — builds mindlink-widget.min.js

Sync: cd backend && node scripts/sync-embed-sdk.mjs

platform-plugin (plugin apps)

Path	What it is
[platform-plugin/README.md](/docs/sdk-platform-plugin)	Mechanism, knowledge sync, embed, plugin_invoke, recognize the open form, bundled skills
`platform-plugin/go/`	Go SDK (session, invoke, `fill_open_form`)
`platform-plugin/js/`	TS / browser SDK (iframe session, report/fill draft)
`platform-plugin/contracts/`	REST and host protocol (including recognize the open form)
`platform-plugin/templates/starter/`	Minimal plugin skeleton (includes a draft example)

Go import example:

require mindlink/sdk/mindlink-plugin v0.0.0
replace mindlink/sdk/mindlink-plugin => ../sdk/platform-plugin/go

agent-capability (agent capabilities)

Conversational capabilities: do not register platform_plugins. See [agent-capability/README.md](/docs/sdk-agent-capability).

appsdk (workspace apps)