Workflow Apps

A Workflow App is a registry of authored workflows for packaged execution surfaces. It provides one app identity, title, default workflow, signal descriptors, and a common runtime.

Define an app​

import { workflowApp } from "@dromio/workflow";

export const reviewApp = workflowApp({
  id: "review-app",
  title: "Response Review",
  defaultWorkflow: responseReview,
  workflows: [responseReview, clarifyRequestWorkflow],
});

workflows must contain at least one authored workflow. If defaultWorkflow is omitted, the first entry is used. An explicit default must also be registered.

Inspect the registry​

reviewApp.defaultWorkflowId;
reviewApp.workflowIds();
reviewApp.listWorkflows();
reviewApp.getWorkflow("response-review");
reviewApp.graph("response-review");

Each workflow remains independently runnable and inspectable; the app does not merge graphs or outputs. reviewApp.definition contains serializable app, workflow, trigger, and signal descriptors.

Prompt adapter constraint​

The root CLI, TUI, GUI, and SVG adapters encode a text prompt into a workflow with exactly one trigger input key. This is an adapter constraint, not a limitation of workflow.start(). Richer workflow inputs can use direct execution or a custom host adapter.

Keep entry points thin​

#!/usr/bin/env bun

import { runWorkflowCli } from "@dromio/workflow";
import { reviewApp } from "./app.js";

await runWorkflowCli(reviewApp);

The app owns workflow registration. The entry point selects a surface and its host options; it must not reconstruct workflow topology.

Add durable hosting​

createWorkflowAppHost() wraps the app runtime with a runtime store, signal control plane, persistence after state changes, and a Fetch-compatible HTTP adapter. Choose {kind: "memory"} for tests or {kind: "sqlite", path} for local persistence. runWorkflowServer() serves that host with Bun.

Persisted runs contain state, events, checkpoints, pending questions, pending hooks, and durable attempt metadata. The host reconciles signal waits at startup and can run delivery passes. External authentication, tenant isolation, retention, and provider-side idempotency remain application responsibilities.

Let an external harness operate the app​

A Workflow App is the registry and durable host boundary that an external harness operates. It exposes the registered workflows, triggers, runs, and pending interactions through the control plane; it does not embed the harness or its model provider. See External harnesses for MCP provider construction, transport, discovery, and dromio.resume_hook.