docs(diagnostics): add the LOADING_ON_ACCESSOR page

scripts/extract-diagnostics.mjs

@@ -76,6 +76,7 @@ const FIX_STARTS = {
 	HEAD_TAG_INVALID: "`non-head-tag`/`invalid-attribute`: only head elements",
 	HOT_SCOPE_RERUNS: "The message names the latest cause",
 	LAZY_ASSET_UNMAPPED: "This is bundler-plugin configuration",
+	LOADING_ON_ACCESSOR: "`on` takes the dependency's value",
 	PENDING_ASYNC_UNTRACKED_READ: "Async values must be read where tracking",
 	RUN_WITH_DISPOSED_OWNER: "This usually means a stale owner",
 	SSR_BOUNDARY_WATERFALL: "The same repairs apply, in the same order",

src/routes/reference/(1)solid-js/(8)diagnostics/(0)index.mdx

@@ -75,6 +75,7 @@ Naming your memos and effects (`{ name }`) turns the trailing `effect` in the `i
 | [`INVARIANT_VIOLATION`](/reference/solid-js/diagnostics/invariant-violation)                           | `error`          | `error`         | Internal consistency check failed (throws under `__TEST__`, reported in dev)                                                                                      |
 | [`LATE_HEADER_WRITE`](/reference/solid-js/diagnostics/late-header-write)                               | `head`           | `error`         | Response header written after the head was sent; dropped (observe + dev; dev throws)                                                                              |
 | [`LAZY_ASSET_UNMAPPED`](/reference/solid-js/diagnostics/lazy-asset-unmapped)                           | `ssr`            | `warn`          | `lazy()` component's client assets could not be resolved for the page (dev)                                                                                       |
+| [`LOADING_ON_ACCESSOR`](/reference/solid-js/diagnostics/loading-on-accessor)                           | `async`          | `warn`          | `<Loading on>` received a function (an accessor) instead of the dependency's value; it is never called, so the boundary never re-arms                             |
 | [`LOADING_ON_OUTSIDE_HOLD`](/reference/solid-js/diagnostics/loading-on-outside-hold)                   | `async`          | `warn`          | `<Loading on>` changed but its data is also read outside the boundary and holds the frame: the fallback can never be seen                                         |
 | [`LONG_HOLD`](/reference/solid-js/diagnostics/long-hold)                                               | `responsiveness` | `info`, `warn`  | Acknowledged hold whose tail (last input → commit) ran 500ms+/1000ms+ (attribution enabled)                                                                       |
 | [`LOWERCASE_EVENT_ATTRIBUTE`](/reference/solid-js/diagnostics/lowercase-event-attribute)               | `render`         | `warn`          | A function was set on a lowercase `on*` (or `on:`) attribute, which is not an event handler in 2.0; use `onXxx` (dev; client)                                     |

src/routes/reference/(1)solid-js/(8)diagnostics/loading-on-accessor.mdx

@@ -0,0 +1,49 @@
+---
+title: "LOADING_ON_ACCESSOR"
+category: "Diagnostics"
+use_cases: "loading_on_accessor diagnostic, console warning repair, diagnostics assertion"
+tags:
+  - "diagnostics"
+  - "async"
+  - "warn"
+  - "reference"
+  - "v2"
+version: "2.0"
+description: "LOADING_ON_ACCESSOR: `<Loading on>` received a function (an accessor) instead of the dependency's value; it is never called, so the boundary never re-arms."
+source_repo: "solidjs/solid"
+source_ref: "next"
+source_path: "packages/solid/skills/reactivity-diagnostics/SKILL.md"
+---
+
+{/* Generated by scripts/extract-diagnostics.mjs from packages/solid/skills/reactivity-diagnostics/SKILL.md and packages/solid/diagnostics.json in solidjs/solid. Edit the skill, then regenerate. */}
+
+`<Loading on>` received a function (an accessor) instead of the dependency's value; it is never called, so the boundary never re-arms.
+
+## What you saw
+
+- **Kind:** `async`
+- **Severity:** `warn` (code that works but is structurally wrong or expensive)
+
+The console report opens with `[LOADING_ON_ACCESSOR]` and the message, then an `in` line naming the owners that enclose the subject, root first, and an `at` line with the source location when the code was compiled with one.
+In a captured artifact the same finding is an event with `code: "LOADING_ON_ACCESSOR"`, `ownerPath`, and `loc`.
+[Diagnostics](/reference/solid-js/diagnostics#read-a-report) explains each line.
+
+## Why it fires
+
+A Loading boundary's `on` received a function, such as `on={route}` or `on={() => route()}`.
+
+## How to fix it
+
+`on` takes the dependency's value, so pass `on={route()}`, or `on={[query(), page()]}` for several dependencies.
+An accessor passed instead is never called, nothing is read, and the boundary never re-arms.
+
+## In tests
+
+`captureArtifact` from `@solidjs/diagnostics` runs a scenario with the diagnostics channel open and returns the events it saw.
+`expectNoDiagnostics(artifact)` fails while `LOADING_ON_ACCESSOR` is among them, with the events as evidence; after the fix, the code is gone from `artifact.diagnostics`.
+[Check for regressions in tests](/guides/debugging-reactivity#check-for-regressions-in-tests) shows the loop and the Vitest matcher form.
+
+## Learn more
+
+- [Diagnostics](/reference/solid-js/diagnostics): every code, with its kind, severity, and trigger.
+- [Debugging reactivity](/guides/debugging-reactivity): how to read a report and what each group of codes points at.