Render charts, QR codes, barcodes, word clouds, tables, Graphviz diagrams and watermarked images as images with QuickChart, and save a chart to a short URL.
QuickChart ships in the w6w first-party pack. It declares 13 actions, 2 health checks, and the host runs its code in a sandbox that never sees the credential.
io.w6w.quickchartQuickChart turns a description into an image. This app exposes its rendering APIs to a workflow.
A workflow can render a Chart.js chart (Chart.js v2, v3 or v4) to PNG, JPEG, WebP, SVG or PDF, save a chart to a short URL that can be dropped into an email or chat message, validate a chart before rendering it, and draft a Chart.js config from a plain-English description. It can also render QR codes (styled, with a centre logo or caption) and read one back from an image, render barcodes in over a hundred symbologies, word clouds, tables, Graphviz diagrams, and watermark one image onto another.
No account is needed: the API answers anonymously within a shared rate limit. A paid API key can be added to the connection for higher limits and longer-lived short URLs; without a connection every action still runs. Images are written to the run’s file store and returned as a file reference; SVG output also comes back as text.
Three routes to the same 13 actions. The Workflow tab is generated from QuickChart's own manifest and carries its real ids, so it is copy-pasteable; the Code and CLI examples are the same call for any action on any app, so every app-specific value in them is a blank you fill in.
barcode-render Render a barcode (Code 128, EAN, UPC, Data Matrix and 100+ more) to an image.
chart-draft-from-text Draft a Chart.js config (and a saved image URL) from a plain-English description.
chart-url-create Save a Chart.js chart and get a short URL that renders it, for email, SMS or chat.
qr-render Render a QR code (optionally styled, with a centre image or caption) to an image.
A workflow step names the app and the action, and the editor fills in the
connection when you pick one. This is the Step shape from the
workflow spec, carrying QuickChart's real ids.
{
"manifestVersion": "2",
"name": "quickchart-example",
"steps": [
{
"id": "barcode-render",
"uses": {
"app": "io.w6w.quickchart",
"action": "barcode-render",
"connection": "conn_YOUR_CONNECTION_ID"
},
"with": {
"type": "<type>",
"text": "<text>"
}
}
]
}barcode-render chart-draft-from-text chart-render chart-url-create chart-validate +8 more actions available
Every app-specific value here is a blank you have to fill in. An
app action is reached through the connection that authenticates it, so the
address is a connection id, not the app id — and connections belong to your account,
so a public page cannot know yours. Create one for QuickChart, then fill in
the three blanks: conn_YOUR_CONNECTION_ID, the action key, and the
parameters that action declares. The call itself is real — the shape is transcribed
from the studio's own snippet builder, which prints the same kind of blanks — but
nothing in it is specific to QuickChart. The Workflow tab is where this app's
real ids are.
npm install @w6w/sdkyarn add @w6w/sdkpnpm add @w6w/sdkdeno add npm:@w6w/sdkimport { W6wClient, isActionRun } from "@w6w/sdk";
// Reads W6W_BASE_URL and W6W_TOKEN from the environment when omitted.
const client = new W6wClient();
const envelope = await client.run({
urn: "conn_YOUR_CONNECTION_ID",
action: "barcode-render",
payload: {
type: "<value>",
text: "<value>",
// format: "<value>",
// width: "<value>",
// height: "<value>",
// scale: "<value>",
// includeText: "<value>",
// rotate: "<value>",
},
});
if (isActionRun(envelope)) console.log(envelope.value); npm install -g @w6w/cli w6w run conn_YOUR_CONNECTION_ID --action barcode-render --payload '{"type":"<value>","text":"<value>"}' Give an AI agent QuickChart — without giving it QuickChart's credentials. One MCP endpoint exposes every app, function and workflow the caller is entitled to, as tools it can discover and run. Access is granted per team while we onboard.
One tool call{
"name": "w6w_invoke",
"arguments": {
"ref": "app:io.w6w.quickchart#barcode-render",
"input": {
"type": "<type>",
"text": "<text>"
}
}
}
Every tool names its target with a single ref. The
app: form above doesn't name a connection at all — the
host resolves which of the caller's QuickChart connections to sign
with, and refuses rather than guesses when the answer is ambiguous.
The token is attached host-side, at the moment of the call. It is never a tool argument, never in the model's context, and never in a transcript — so a prompt injection has nothing to exfiltrate.
Tools are derived per end user from what that person has actually connected and is entitled to — not one shared bot identity carrying the union of everyone's access.
Multi-step work runs on the workflow engine and returns a run handle the agent can poll — retries, branching and state survive the conversation that started them.
QuickChart's declared health checks are on the surface too, so an agent can tell "the vendor is down" from "your credential expired" before it burns a retry on either.
The MCP surface is part of the hosted platform. QuickChart itself is MIT, and the runtime that executes it is source-available (FSL).
QuickChart declares its own checks, so its health is a property of the app rather than something the host guesses at.
GET /healthcheck — expects {success: true, version}.