# DevTools coverage > Which Lit concepts the DevTools panel shows, where to find each one, and what it does not show. Each Lit concept below has a row: where the panel shows it, and what it leaves out. Use it to check whether the panel can answer your question before you go looking; for how to use each view, read the [DevTools guides](/guides/devtools/). Status is one of **shown**, **partly shown** or **not shown**. The element tree, element details and update records are also open to agents over MCP; see [Agents](/guides/devtools/agents/). ## Elements and state | Concept | Status | Where | Not shown | | ------------------------- | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- | | Element tree | shown | [Components tree](/guides/devtools/components/#browse-the-tree), through shadow roots and light DOM; a tag nothing has defined sits in its place with a *not defined* chip, and a custom element another library defined stays in place | Plain HTML elements, which the tree flattens away | | Custom element registry | not shown | — | The list of defined tags, and scoped registries | | Reactive properties | shown | [Properties table](/guides/devtools/components/#read-the-details-pane), with the attribute name, a reflects badge and badges for the `hasChanged`, `converter`, `noAccessor`, `useDefault` and `attribute: false` options | Values are read-only. Badges show an option is set, not what a custom function does | | `@state` | shown | State table | Values are read-only | | Attributes | shown | Attributes table, live | When a reflected property wrote its attribute | | Shadow DOM | shown | `shadow root`, `light DOM`, `closed` and `delegatesFocus` flags in the details pane | — | | Slots | shown | [Anatomy](/guides/devtools/components/#see-an-elements-slots-and-parts) overlay and Slots table: assigned elements, fallback, forwarding, children no slot takes | — | | Reactive controllers | shown | Instance table, named by the field that holds them | Calls to `hostConnected`, `hostUpdate` and the other host hooks | | `@query` and its siblings | not shown | A queried element can appear as a plain field in the Instance table | The selector and what it matched | | Form-associated elements | not shown | — | `ElementInternals`, form value and validity | | Source location | shown | Source link and **Rendered at** link in the details pane, which open in the editor or, in Chrome’s extension, the Sources panel; **Reveal in Elements** in the extension; [source overlay](/guides/source-overlay/) | — | ## Updates and rendering | Concept | Status | Where | Not shown | | -------------------------- | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------- | | Update lifecycle | shown | Lit Lifecycle [layer](/guides/devtools/timeline/#choose-layers): `connectedCallback`, `performUpdate`, `willUpdate`, `update`, `updated`, `firstUpdated`, `disconnectedCallback`; an `update skipped` event when `shouldUpdate` returns false, counted in the [Updates table](/guides/devtools/updates/#read-one-components-updates) | `render` on its own, and `updateComplete` | | Changed properties | shown | [Updates tab](/guides/devtools/updates/#see-the-old-and-new-values), with old and new values when the Changed values layer is on | — | | Update cause | shown | Recorded at `requestUpdate`, as the updating component, the mouse, keyboard or custom event being handled, or the `@lit/task` run that settled; the Timeline list draws the chain to its cause and the Updates tab names it | Which line of code called `requestUpdate` or set the property | | Errors in an update | shown | Updates tab, *threw in update* rows | Errors from timers or listeners the component set up | | Render timing | shown | Lit Render layer; Chrome Performance tracks | A flamechart inside the panel | | Re-render frequency | shown | [Updates table](/guides/devtools/updates/#read-the-component-table); [flash on update](/guides/devtools/components/#flash-elements-that-update) | Updates whose output did not change | | Template parts and commits | partly shown | Lit Render (verbose) layer, one event per binding | A view of a template’s parts, and template cache hits | | Directives | not shown | Their commits appear in the verbose layer, unlabelled | Which directive produced a commit | | Event listeners | partly shown | Custom events layer records each event a component dispatches, with its flags and detail, and the Components tab counts them per type; verbose layer records each `@event` listener commit; Mouse and Keyboard layers record input | `@eventOptions`, and which listeners ran for an event | | Styles | partly shown | `::part` exports, including ones forwarded with `exportparts`, in the Anatomy overlay and Parts table; custom properties a [Custom Elements Manifest](/guides/devtools/components/#read-a-components-documentation) documents, in **CSS properties** | `static styles`, adopted stylesheets, and custom properties no manifest documents. Use the browser’s Elements panel | | Dev-mode warnings | shown | `warning` events on their own Lit warnings layer, a chip on the component’s tree row and a count on the Components tab, and a chip and **Warnings** section in the [details pane](/guides/devtools/components/#read-the-details-pane); the multiple-Lit-versions check also sits in the About block | Which instance caused a warning when the message names only a tag, and warnings an app silenced by code. A production build of Lit issues none | | Hot patches | shown | HMR banner and tab badge; see [HMR](/guides/hmr/) | — | ## Lit libraries | Library | Status | Where | Not shown | | -------------------------------------- | ------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------- | | `@lit/task` | shown | Instance table with status and value or error; failures in Updates; each run as a `task` row on the Timeline, from the update that started it to when it settled | Runs started before its element’s first recorded update | | `@lit-labs/signals` | partly shown | Instance table shows a signal’s value | Computed values, which are never evaluated; the `SignalWatcher` mixin; which signals an element reads | | `@lit/context` | partly shown | Instance table lists each provider and consumer with its key and value; a consumer links to its provider and a provider to its consumers | Consumers that did not ask for updates, which a provider does not record; which context root holds a waiting request | | `@lit-labs/virtualizer` | not shown | — | — | | `@lit/localize` | not shown | — | — | | `@lit-labs/ssr` | partly shown | Components tab marks a server-rendered element with a `deferred`, `not hydrated` or `hydrated` pill | SSR internals, and a page overlay of hydration state | | `@lit-labs/router`, `@lit-labs/motion` | not shown | — | — | All of these libraries keep their state across a hot patch; see [Ecosystem](/guides/ecosystem/). ## Related [Inspect live components](/guides/devtools/components/)The tree, the details pane and the element picker. [Limitations](/reference/limitations/)The component shapes a hot patch cannot update in place.