Application API

Import application composition APIs from @flue/runtime/app.

app.ts

app.ts is an optional authored application entrypoint. Without it, Flue generates an application that mounts flue() at /. When app.ts exists, its default export owns the request pipeline and must mount flue() explicitly to publish Flue routes.

import { flue } from '@flue/runtime/app';
import { Hono } from 'hono';

const app = new Hono();
app.route('/', flue());
export default app;

See Routing for middleware, custom routes, prefixes, and application-owned dispatch.

Fetchable

interface Fetchable {
  fetch(request: Request, env?: unknown, ctx?: unknown): Response | Promise<Response>;
}

Structural contract for the default export of an authored app.ts entry. Any object exposing a compatible fetch() method satisfies it, including a new Hono() instance.

On Cloudflare, env contains bindings and ctx is the ExecutionContext. On Node, env contains Hono’s Node adapter bindings for the incoming and outgoing messages, and ctx is undefined.

flue()

function flue(): Hono;

Creates a mountable Hono sub-app for Flue’s public HTTP and WebSocket API. Routes are relative to the application-chosen mount prefix.

Route	Purpose
GET /openapi.json	Return the public OpenAPI document.
POST /agents/:name/:id	Prompt an HTTP-exposed agent instance.
GET /agents/:name/:id	Upgrade to a WebSocket connection for a WebSocket-exposed agent instance.
POST /workflows/:name	Start an HTTP-exposed workflow run.
GET /workflows/:name	Upgrade to a WebSocket invocation for a WebSocket-exposed workflow.
GET /runs/:runId	Retrieve a workflow run record.
GET /runs/:runId/events	Retrieve persisted workflow run events.
GET /runs/:runId/stream	Stream workflow run events over SSE.

Agent and workflow routes are available only when the corresponding module opts into that transport. Run routes inspect workflow runs only and may expose payloads, results, errors, and events. Applications publishing them should authorize access to the selected run. Direct agent prompts and dispatched agent inputs are not runs.

admin()

function admin(): Hono;

Creates a mountable Hono sub-app for read-only deployment inspection. Mount it explicitly beneath an application-chosen prefix and protect that mount with application-owned authorization.

import { admin, flue } from '@flue/runtime/app';
import { Hono, type MiddlewareHandler } from 'hono';
import { authenticateOperator } from './auth.ts';

const requireOperator: MiddlewareHandler = async (c, next) => {
  if (!(await authenticateOperator(c.req.raw))) {
    return c.json({ error: 'Unauthorized' }, 401);
  }

  await next();
};

const app = new Hono();
app.route('/', flue());
app.use('/admin/*', requireOperator);
app.route('/admin', admin());
export default app;

Route	Purpose
GET /openapi.json	Return the administrative OpenAPI document.
GET /agents	List built agents and their transport metadata.
GET /runs	List workflow run summaries.
GET /runs/:runId	Retrieve a workflow run record.