DOCS

Everything QDev does,
in one place.

QDev opens any JSON, YAML, or TOON file as a tree, an inferred schema, and a graph — then writes and runs jq from your schema when you ask in plain English. This page covers installing it, the views, the ⌘K bar, the AI modes, and every shortcut.

Views & root

→

The four views, and reframing any node as the document root.

Previews

→

The inline peek, the hover popover, and tuning them in Tree settings.

Themes

→

Nine presets, importing a VS Code theme, and how your choice sticks.

Install & open a file

QDev is a browser extension. Add it once and it takes over JSON, YAML, and TOON files automatically — local file://paths and URLs alike. There's nothing to open; navigate to a file and it renders as a tree.

Add to Chrome Add to Firefox

What it opens

FORMAT	OPENS ON	HOW IT'S DETECTED
JSON	.json	By content-type, file extension, or JSON shape — including raw and mislabeled text/plain responses.
YAML	.yaml / .yml	By content-type or extension. Detection is conservative — no shape-sniffing.
TOON	.toon	By file extension. TOON has no content-type of its own.

Very large files (over 64 MB) load through a streaming path so the tab stays responsive. If a JSON response is mislabeled as text/plain, QDev still recognizes it.

The four views

Switch between views from the toolbar. They all read the same document — no reloading, no re-parsing.

Tree

The interactive collapsible tree. Expand or collapse any subtree, expand/collapse all, toggle line numbers, and virtualized so it stays smooth on huge files.

Raw

The document text in its own format — YAML stays YAML, TOON stays TOON — for when you just want to read or copy the source.

Schema

An inferred JSON Schema of your data, rendered in the same interactive tree. The fastest way to understand the shape of an unfamiliar payload.

Graph

A node-graph explorer with a minimap and level-of-detail zoom, plus its own search box — great for tracing relationships across nested objects.

The `⌘K` bar

One bar does four things. Press ⌘ K (or Ctrl K) to focus it, then type — QDev routes what you type to the right engine by how it reads. You can force a mode with a prefix.

a bare word or phrase

Full-text search across keys, values, and paths. Scope it with key:, value:, or path: prefixes. Results rank in the dropdown; Enter jumps to the node.

starts with > or looks like jq

Writes and runs a jq program against the document and shows the transformed result with a match count.

Ask AI

starts with ? or reads like a question

Sends your question to the AI, which writes jq from your schema, runs it, and drops the program back into the bar. It can ask a clarifying question and shows its step trail.

SQL

starts with SELECT / WITH

When the document is a tabular top-level array, query it with SQL instead of jq.

AI modes

QDev can write jq four ways. In AI settingsyou keep them as an ordered, toggleable list — a query walks the enabled modes top to bottom and uses the first one that's available. Drag to reorder, toggle to disable. Hosted is skipped unless you're signed in with a plan.

Hosted (QDev Pro)

RECOMMENDED

Runs the model server-side — no install, no GPU, best jq accuracy, identical on Chrome and Firefox. Only your schema and question leave the tab; your values never do. Requires a QDev Pro plan.

Ollama

LOCAL · ADVANCED

Points QDev at a local Ollama server (default localhost:11434) for the strongest local models. Set the endpoint and model in AI settings; the panel detects reachability live. Nothing leaves the device.

Chrome built-in

LOCAL · CHROME ONLY

Uses Chrome's on-device Gemini Nano via the Prompt API. No download you manage, fully local — best for light, occasional asks on a recent Chrome.

WebLLM

LOCAL · WEBGPU

Runs a model in the page via WebGPU — nothing at all leaves the device. Pick a preset (Qwen 3B, Qwen Coder 7B, Llama 8B) or a custom model id; weights download on first use.

Not sure which to pick? Compare all four modes or read the limits of local AI.

Connect QDev Pro (or bring your own)

Hosted mode needs your browser linked to a QDev account. In the extension, open AI settings → Sign in. That opens a tab on this site — sign in, and the browser is linked for entitlement checks. No API key to paste; the token is minted for you after sign-in.

1In the extension, open AI settings and choose Sign in.
2Sign in (or subscribe to QDev Pro) in the tab that opens.
3The tab confirms “All set ✓” — close it and go back to your file.
4Press ⌘K and ask your JSON anything.

NO PLAN? STILL FREE

You don't need Pro to use AI. Enable Ollama, Chrome built-in, or WebLLM in AI settings and QDev writes jq entirely on your device — no account required.

Keyboard shortcuts

On Windows and Linux, use Ctrl where these show ⌘.

⌘ K

Focus the search bar — search, run jq, or ask AI

⌘ S

Download the current view in the document's format

⌘ A

Select all and copy the raw document (outside a text field)

⌘ + click

Toggle a whole subtree open/closed in the tree or graph

↑ ↓

Move through search / graph results in the dropdown

Tab / →

Accept a jq completion

Enter

Run the selected result or query

Esc

Close the dropdown, a dialog, or the graph help

● YOUR DATA STAYS YOURS

Where your data goes — and doesn't

Your file is parsed and rendered entirely in the tab. The local AI modes send nothing at all off the device. Hosted mode sends only your schema (field names and types) and your question, through a stateless proxy that is zero-retention by default — never your values. Connecting your account only links it for entitlement checks.

Read the full privacy details →

Add it and open a file.

Free for personal use, on Chrome and Firefox. Turn on hosted AI when you want the best jq accuracy.

Add to Chrome

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Everything QDev does,in one place.