diff --git a/docs/scheduler/observability.md b/docs/scheduler/observability.md
index d56a5e44..5b8e7cf4 100644
--- a/docs/scheduler/observability.md
+++ b/docs/scheduler/observability.md
@@ -260,19 +260,49 @@ while lines that never had one signal nothing of the sort.
 
 The stored field is `severity_text`, and Grafana's log-level buttons filter on
 a field called `level` — a name no row here carries. That is not something the
-pipeline can fix: VictoriaLogs' OTLP ingester chooses the stored name itself,
-and its ingest parameters have no option to rename it.
+pipeline can fix: VictoriaLogs' OTLP ingester names the stored field
+`severity_text` unconditionally (v1.52.0, `app/vlinsert/opentelemetry/pb.go`),
+and its ingest parameters have no `_level_field` sibling to rename it with.
 
 So the datasource is told instead. `nix/host-modules/swarm-grafana.nix`
 provisions the VictoriaLogs datasource with a `logLevelRules` entry per
 severity in the table above, each matching `severity_text` against one of
 those values — which is the plugin's way of saying "the level lives in this
-field". A level button then filters on `level` **or** the matching
-`severity_text`, and the store answers the second half.
+field". `logLevelRules` is the datasource plugin's own jsonData key and the
+only level-related one it has — there is no single "the level lives in field
+X" string to set, so mapping every level takes one rule each. A level button
+then filters on `level` **or** the matching `severity_text`, and the store
+answers the second half. Each enabled rule appends an `OR
+<field>:<op>"<value>"` term to the query a level button emits, beside the
+`level:…` term that matches nothing here. Clicking "info" goes from
 
-`Unspecified` is deliberately left out of those rules, so rows with no
-severity stay unfiltered by every level button and keep showing up in the
-panel that counts them.
+```
+level:contains_common_case("info","information","informational","notice")
+```
+
+to that OR `severity_text:="INFO"`, which our rows do match.
+
+`Unspecified` is deliberately left out of those rules. It is VictoriaLogs' own
+rendering of an absent severity, and it is what the **Log rows with no
+severity** panel counts — giving it a level would dress the missing data up
+as a colour and retire the instrument that measures it.
+
+#### Three ways to get a `logLevelRules` entry wrong, all of them silent
+
+Grafana accepts any jsonData it does not recognise, so a bad rule provisions
+cleanly and the affected level button goes on returning zero rows:
+
+- `enabled` must be literally `true`, not merely not-false. The query
+  builder keeps rules on `rule.enabled` being truthy while the row colouring
+  path keeps them on `!== false`, so an omitted flag colours rows correctly
+  and leaves the buttons broken — working in the half nobody is looking at.
+- `level` must be a canonical Grafana `LogLevel` value. The builder groups
+  rules by it and only ever looks up `critical`, `error`, `warning`, `info`,
+  `debug`, `trace`; `warn` and `fatal` are enum aliases that resolve to
+  other spellings and match no group.
+- `value` is compared with `===`, so it must be the severity text exactly as
+  stored: the uppercase OpenTelemetry short names `overwrite_text` writes in
+  `nix/journald-severity.nix`, not that table's lowercase keys.
 
 ## Host-emitted container-resource metrics (hive-c0re)
 
diff --git a/nix/host-modules/swarm-grafana.nix b/nix/host-modules/swarm-grafana.nix
index aaa301bd..5e6ac674 100644
--- a/nix/host-modules/swarm-grafana.nix
+++ b/nix/host-modules/swarm-grafana.nix
@@ -41,46 +41,19 @@ let
   logsDatasourceUid = "swarm-victorialogs";
 
   # Which field carries the log level, told to the READER because the writer
-  # cannot be told. Grafana's log-level buttons filter on a field called
-  # `level`, and no row in this store has one: VictoriaLogs' OTLP ingester
-  # names the stored field `severity_text` unconditionally (v1.52.0,
-  # `app/vlinsert/opentelemetry/pb.go`) and its ingest parameters have no
-  # `_level_field` sibling to rename it with. So the mapping is made here.
+  # cannot be told: VictoriaLogs' OTLP ingester names the stored field
+  # `severity_text` unconditionally, with no option to rename it, but
+  # Grafana's log-level buttons filter on a field called `level`. So the
+  # mapping is made here, one `logLevelRules` entry per level below.
   #
-  # `logLevelRules` is the datasource plugin's own jsonData key and the only
-  # level-related one it has — there is no "the level lives in field X"
-  # string to set. A rule names its own field, so saying it takes one rule
-  # per level.
-  #
-  # 🔑 Each enabled rule appends an `OR <field>:<op>"<value>"` term to the
-  # query a level button emits, beside the `level:…` term that matches
-  # nothing here. Clicking "info" goes from
-  #
-  #   level:contains_common_case("info","information","informational","notice")
-  #
-  # to that OR `severity_text:="INFO"`, which our rows do match.
-  #
-  # ⚠️ Three ways to get a rule wrong, all of them SILENT — Grafana accepts
-  # any jsonData it does not recognise, so a bad rule provisions cleanly and
-  # the buttons go on returning zero:
-  #
-  #  - `enabled` must be literally `true`, not merely not-false. The query
-  #    builder keeps rules on `rule.enabled` being truthy while the row
-  #    colouring path keeps them on `!== false`, so an omitted flag colours
-  #    rows correctly and leaves the buttons broken — working in the half
-  #    nobody is looking at.
-  #  - `level` must be a CANONICAL Grafana `LogLevel` value. The builder
-  #    groups rules by it and only ever looks up `critical`, `error`,
-  #    `warning`, `info`, `debug`, `trace`; `warn` and `fatal` are enum
-  #    aliases that resolve to other spellings and match no group.
-  #  - `value` is compared with `===`, so it is the severity text exactly as
-  #    STORED: the uppercase OpenTelemetry short names `overwrite_text`
-  #    writes in ../journald-severity.nix, not that table's lowercase keys.
-  #
-  # `Unspecified` is deliberately unmapped. It is VictoriaLogs' own rendering
-  # of an absent severity, and it is what the logs dashboard's "no severity"
-  # panel counts — giving it a level would dress the missing data up as a
-  # colour and retire the instrument that measures it.
+  # 🔑 A rule wrong in any of three ways provisions cleanly and its level
+  # button silently returns zero rows — `enabled` must be literally `true`,
+  # `level` must be a canonical Grafana `LogLevel` (not an alias like `warn`
+  # or `fatal`), and `value` must match ../journald-severity.nix's uppercase
+  # STORED text, not its lowercase keys. `Unspecified` is deliberately left
+  # unmapped so the "no severity" panel keeps counting it. Full walkthrough
+  # (why each rule shape is what it is, the query a level button actually
+  # emits): docs/scheduler/observability.md#why-explores-level-buttons-need-the-datasource-told
   logLevelRules =
     let
       fromSeverityText = value: level: {