---
title: BxLens for ColdBox
order: 5
description: See inside a ColdBox application without changing it: events, views, layouts, the event cache, modules, schedulers, findings, boards and Lensy.
icon: lucide:layers
---

# BxLens for ColdBox

![ColdBox](../assets/coldbox-icon-full.svg){ width=64 }

BxLens understands [ColdBox](https://coldbox.ortusbooks.com). When your application is a ColdBox application, BxLens finds it by itself and shows what ColdBox does for every request. You install nothing in your application and you change no file.

| You get | Where |
|---|---|
| A **ColdBox** tab: the route, event, handler, layout and view, how many views rendered and which ones more than once, the time of each view and layout in a waterfall, and the state of the event cache | [The bar](../lensbar/coldbox.md) |
| The ColdBox **tag** and the **event** on every request, and a filter by tag | [Requests](../console/index.md#requests) |
| The events, views and layouts in the **Timeline**, with the queries that ran inside them | [Timeline](../lensbar/timeline.md) |
| Buttons to **clear the event and view caches** and to **reinit** the framework | [The bar](../lensbar/coldbox.md#buttons) |
| The ColdBox version next to the application | [Applications](../console/applications.md) |
| A **ColdBox page** in the console: overview, composition, modules (timeline, tree, table and which version loaded), schedulers and tasks, CacheBox caches and executors | [The ColdBox page](../console/coldbox.md) |
| **Findings** of the Advisor, in the bar and in the console, free. With BoxLang+, **Find solution** asks Lensy for a prompt for your coding agent | [Findings](../console/coldbox.md#findings) |
| **Task groups and meta**, for BoxLang and ColdBox tasks, free. Run, pause, resume and remove need BoxLang+ | [Tasks](../console/tasks.md#groups) |
| **Boards** on the Reports page: what to look at first, for the whole server and for your application | [Reports](../console/errors-and-reports.md#boards) |
| **Help icons** and a **Glossary** for every term | [Glossary](../reference/glossary.md) |
| **Lensy tools** to read the application and, with your approval, to act on it | [Lensy tools](../reference/ai-tools.md#coldbox) |

Watch the [ColdBox walkthrough](../walkthroughs.md#coldbox) for a tour with a voice and captions.

## How it works

1. At the start of each request BxLens looks for `application.cbController`, where ColdBox keeps its controller.
2. If it finds one, BxLens registers **one interceptor of its own** in that ColdBox application, with ColdBox's own interceptor service. It is the same mechanism a ColdBox module uses, and nothing in your files changes.
3. The interceptor tells BxLens, for each interception point, which event ran, which view or layout rendered and how long it took. It sends **names, numbers and flags**, never the values of `rc` or `prc`.
4. `?fwreinit` makes ColdBox build a new controller. BxLens sees the new one on the next request and registers again.

There is nothing to switch on. The support is on by default and does nothing until a ColdBox application is found. Turn it off with `collectors.coldbox.enabled`.

## The console page

The console has a [ColdBox page](../console/coldbox.md): overview, composition (routes, handlers, interceptors), modules with a timeline, a tree and a duplicate-version check, CacheBox caches and executors.

## What it costs

At `collect.level` `light` (the default) BxLens uses three interception points of ColdBox and reads the request facts once at the end. At `full` it also times every event, view and layout. Both are small next to the work a request does, and the data is dropped with the request.

## Replacing cbdebugger

The ColdBox debugger shows a panel at the end of each request in development. BxLens shows the same facts, and it is safe to leave on in production because it is only shown to the callers you allow and it never records the values of `rc` or `prc`.

| cbdebugger | BxLens |
|---|---|
| Request profiler list | The [Requests](../console/index.md#requests) page with the ColdBox tag and event |
| Timers for events, views and layouts | The [ColdBox tab](../lensbar/coldbox.md) waterfall and the [Timeline](../lensbar/timeline.md) |
| Route, event, view and layout of the request | The ColdBox tab |
| `rc` and `prc` collections | The names of the keys, never the values |
| SQL panels for qb, Quick and cborm | The [Queries](../lensbar/queries.md) tab sees every query, whatever library ran it |
| CacheBox monitor: clear events and views | Clear event cache and Clear view cache in the bar |
| Debug mode and password | `bar.access`, which says who sees the bar. There is nothing to turn on |

You can run both. If you only want BxLens, remove cbdebugger from the application.

## Other frameworks

ColdBox is detected by itself. Any other framework, module or application can tag its requests and name its framework with [`lensTag`](bifs.md#lenstag) and [`lensFramework`](bifs.md#lensframework), or from an interceptor with the [extension API](extending.md). A tagged request shows its tag in the Requests page and can be filtered by it.

## Limits

- ColdBox 7 and 8.
- BxLens records the keys of `rc` and `prc`, not their values. There is no setting to turn the values on.
- The request is recorded from ColdBox's interception points. A request that never reaches ColdBox (a static file, a redirect before ColdBox starts) has no ColdBox data.