Quickstart

From nothing to a typed package your application can call. Roughly ten minutes, most of it waiting on a browser tab.

This assumes you already have an Engine to talk to — hosted, or one you started yourself. If not, get one running first; every command below needs it.

Install

curl -sSL https://raw.githubusercontent.com/Usefused/cli/main/install.sh | bash
fused-cli --version

For automated or non-interactive installs, set ASSUME_YES=1 to skip the confirmation prompt.

fused-cli login

This opens your Engine’s sign-in page and saves a subject-scoped credential after you approve it. The credential never passes through the browser and is never printed.

fused-cli whoami

On a headless machine, fused-cli login --no-browser prints the URL instead of trying to open one.

Choose your service’s authentication

For a supported OAuth integration, use a Managed service to connect users without registering your own provider app. Alternatively, store your own credentials. Managed auth is an explicit app configuration choice; init does not automatically choose it when local credentials are missing. Use --no-apply while preparing the managed reference, then plan and apply the completed config.

Build and configure an SDK

fused-cli init support-sdk --sdk --service linear

fused-cli init searches your workspace and then the Registry, pins a concrete service version, and asks what the SDK should expose. All operations is highlighted by default, so press Enter to take the complete service. Open Choose operations… to search by operation ID, method, path, summary, or tag and build a narrower SDK. You do not need to know operation IDs before you start. If activation is needed, the CLI shows one combined confirmation. It keeps governance intact by writing separate workspace and SDK receipts. Missing provider credentials do not block creation: in a terminal the CLI offers to store them securely and retry planning once, while skipping that optional step still publishes the app. When the command succeeds, the SDK is applied and its package is downloaded with generated first-call guidance. It creates only the desired state you chose: the SDK config, plus a workspace config when service activation was needed. If no suitable Registry service exists, import the API yourself from a spec, a GraphQL endpoint, or the provider’s documentation.

The first successful initialization prints the SDK execution token once. Capture it now — a repeat apply will not show it again.

Automating this? Run fused-cli init support-sdk --sdk --service linear --select-all linear --no-input; missing credentials are reported as readiness metadata without blocking publication. You may pre-provision them with secret set --no-input --value-stdin, or let the first affected call return the exact safe setup command. Use an explicit --operation instead when the app needs a narrower surface. The command fails rather than guessing its mode, an ambiguous service, or a capability boundary. For structured plan and apply output with independent retry boundaries, use the advanced controlled workflow.

Call it

Three ways in. Same Engine execution behind all of them, and the same execution token.

Way	Reach for it when	What it needs
`fused-cli sdk invoke`	Checking the path works, or poking an operation by hand	The CLI and the token
The typed package	Your application calls this for real	The downloaded package and the Engine’s gRPC address
`POST /v1/apps/{id}/executions`	You are not in TypeScript or Python, or you would rather not ship a package	The Engine’s HTTP address and the version ID from apply

export FUSED_SDK_TOKEN='...'

fused-cli sdk invoke support-sdk@1.0.0 issueUpdate \
  --params '{"id":"ISS-42","state":"done"}'

import { FusedSDK } from 'support-sdk';

const sdk = new FusedSDK({
  grpcUrl: process.env.FUSED_ENGINE_GRPC_URL,
  token: process.env.FUSED_SDK_TOKEN!,
});

const result = await sdk.Linear.issueUpdate({ id: 'ISS-42', state: 'done' });
if (result.ok) console.log(result.data);

curl -X POST "$FUSED_ENGINE_URL/v1/apps/$VERSION_ID/executions" \
  -H "Authorization: Bearer $FUSED_SDK_TOKEN" \
  -H 'Content-Type: application/json' \
  -d '{"operation":"issueUpdate","input":{"id":"ISS-42","state":"done"}}'

A call returns { ok, status, data, error } rather than the payload itself, and services sit on the client in PascalCase with operations following the provider’s own grouping — so issueUpdate may be sdk.Linear.issues.update. Using it in your app covers the whole shape; your package’s generated README.md lists the exact paths for the operations you selected. Whichever one you used, the receipt is the same:

fused-cli sdk activity support-sdk@1.0.0

It shows what ran, how long the provider took, and what came back.

What you just did

workspace  →  approved a concrete service version when it was missing
bucket     →  supplied a credential your code will never see
app        →  published an immutable, typed SDK version with its own receipt

Where to go next

Build an SDK properly

Multiple services, operation selection, and choosing an auth scheme.

Deploy an MCP server

The same approved operations, shaped for an agent.

Connect user accounts

OAuth per end user, with refresh handled by the Engine.

Share access

Give a team what it needs without giving it everything.

Prefer your coding agent to drive this?

The CLI ships skills that teach Claude Code, Codex, Cursor, Windsurf, and Antigravity the exact workflows above.

fused-cli skill list
fused-cli skill install --for claude

Taking this further

You have a working SDK on a Dev license. The tiers above it are about production licensing, SSO, and support — not about unlocking features you have just been using. When you need those, register interest and we’ll size it with you.

Get Started

Guides

Advanced

Reference

Install

Choose your service’s authentication

Build and configure an SDK

Call it

What you just did

Where to go next

Build an SDK properly

Deploy an MCP server

Connect user accounts

Share access

Prefer your coding agent to drive this?

Taking this further

​Install

​Sign in

​Choose your service’s authentication

​Build and configure an SDK

​Call it

​What you just did

​Where to go next

Build an SDK properly

Deploy an MCP server

Connect user accounts

Share access

​Prefer your coding agent to drive this?

​Taking this further

Install

Sign in

Choose your service’s authentication

Build and configure an SDK

Call it

What you just did

Where to go next

Prefer your coding agent to drive this?

Taking this further