llmassisted · Sep 28, 2026 · Sep 27, 2026 · Sep 27, 2026
diff --git a/Tools/parity_dispositions.json b/Tools/parity_dispositions.json
@@ -289,14 +289,6 @@
       "platform": "kotlin",
       "rationale": "Android port of the Swift Test Centre feature-mode experiment (#2105, OURA_PROTOCOL.md s7.5) for this Android-first fork. The Swift twins already exist in Packages/OuraProtocol; the Kotlin builders keep the same bytes and are reachable only from the Android Test Centre behind a confirmation, never automatically."
     },
-    {
-      "type": "platform_specific",
-      "kind": "add-unpaired-constant",
-      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/EventTags.kt::SPO2_R_PI_UNDECODED",
-      "identity_sha256": "a3712c91c37eb0465f18ce767a15017a29039d9de56adbc252a10e3b5ac4db76",
-      "platform": "kotlin",
-      "rationale": "Android-only capture constant for the never-received 0x8b spo2_r_pi tag (OURA_PROTOCOL.md s6.5.1): the history drain logs its first raw payloads as decoder fixtures. No layout is decoded or stored."
-    },
     {
       "type": "platform_specific",
       "kind": "add-unpaired-function",
@@ -424,6 +416,126 @@
       "identity_sha256": "66bff0ba4ddae17d3628a64dcd7e16e27d5f6b979b0971f36a92d5111b379bb9",
       "platform": "kotlin",
       "rationale": "Kotlin twin of the Swift OuraActivityEstimator (Packages/OuraProtocol/.../ActivityEstimate.swift). Byte-identical output is pinned by OuraActivityEstimatorTest against the verbatim stdout of the Swift source compiled standalone over 300 generated inputs; the ledger cannot pair it by name because both platforms overload `estimate`."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::COEF_A",
+      "identity_sha256": "a2056e203b381c266ca9fced680aeb0a7a7c7543a42cc22b46c9eda98e709fcc",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::COEF_B",
+      "identity_sha256": "51718cd3f6b5f9f87080fc1eba1e0e183450a7fc8337f27e8818b66e4ecc6ed3",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::COEF_C",
+      "identity_sha256": "fa9e607f89e17d69777e680f8f7efd8f8985420c192d6c5652d2640ccccce277",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::MAX_PERCENT",
+      "identity_sha256": "73e5812e7a5f4625fb87a0e766fc6b093b8ae6d6ef623206c85c76dc4e9d2d9e",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::MIN_PERCENT",
+      "identity_sha256": "816ea049dde93987ac87346ede773b28a9daa58c8da521a137e9e75c830ad2cc",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-file",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt",
+      "identity_sha256": "b0d142779a18682c88f529ad0d49551e5b9d2c1a44bcf0b1fba721e5164bb46c",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/Decoders.kt::decodeSpO2RatioPi/1#1",
+      "identity_sha256": "52d3b869b4ac64313faef0c0a61e4ea86f2dbf7a725d9540ed83dabad435fe59",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/oura/OuraSpO2Ratio.kt::percent/1#1",
+      "identity_sha256": "c513f2be9fff544a5dbee95f54f28458bec979b5a3c57292191ac3f88f1970a7",
+      "platform": "kotlin",
+      "rationale": "Android-only decode of the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1) into a phone-derived SpO2 percentage (gen4 quadratic cited from [open_oura-spo2]), tagged r_pi_pct and surfaced only through the SpO2 estimate display path. The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt::PI_SATURATED",
+      "identity_sha256": "feee8e608022c383aeefe7a840e7497f3640db2617bbf6ce88d4b69abbd0ccce",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-constant",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/data/OuraStreamMapping.kt::EVENT_SPO2_RPI",
+      "identity_sha256": "26f18c6f9913d8c83e972c3634a1606a0afcbeb5d597b4a648261fbe03d45c80",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-file",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt",
+      "identity_sha256": "a16ec04e9d1b7686c3124bc55776e0e118509f00793dbc90d02c3e08b26f088f",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/IntelligenceEngine.kt::spo2CandidateMean/7#1",
+      "identity_sha256": "e841530d08842be977ebce724b46f9f262179fbb267da49ed6a044ca7d491fcd",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt::displayMean/1#1",
+      "identity_sha256": "0621d0de852cbe823ae18586bf47c6f051ea174f233bf5ca4f86184ef9b73b70",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt::line/1#1",
+      "identity_sha256": "93eeafaac3d4b2801eb6d7b3550a676417f4d1a1796d24a4090f993397dca6f6",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
+    },
+    {
+      "type": "platform_specific",
+      "kind": "add-unpaired-function",
+      "identity": "kotlin\u0000android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt::summary/2#1",
+      "identity_sha256": "a77f37236a04c46f1900b9279980bd468a5ec3a357e02e9d2960a677cc81e21c",
+      "platform": "kotlin",
+      "rationale": "Android-only storage and nightly estimate for the Ring 4 0x8b spo2_r_pi stream (OURA_PROTOCOL.md s6.5.1): records are kept verbatim as OURA_SPO2_RPI events and converted at read time into the Oura SpO2 estimate (never spo2Pct, never scored). The fork's SpO2 feature-mode enable is Android-only, so only this platform receives 0x8b."
     }
   ]
 }
diff --git a/Tools/parity_twin_map.json b/Tools/parity_twin_map.json
@@ -18,17 +18,17 @@
     ]
   },
   "authority": {
-    "files": {"count": 506, "sha256": "7c1aa896ae06001a3869be1164233da7d6af9f909334334a917be56b4832c511"},
-    "functions": {"count": 4503, "sha256": "3cd89d9b79d6228b0e44fc2c89b272eb76a54a903e805bcec142f6da416cbce5"},
+    "files": {"count": 508, "sha256": "b7ab504f627dff2fb8c43c5021fd3ab02c75106f76ed9c6d15cd36e90cfce80a"},
+    "functions": {"count": 4508, "sha256": "3ce3f292737744b7395a8c8e1225db4dd09e7d5c5ef18a216cce470dad5113c2"},
     "properties": {"count": 464, "sha256": "85338b70168a36af785255eb8959a41272cc02334529c2e3ef2a7d18444c7ef7"},
-    "constants": {"count": 1968, "sha256": "2c88ab0d322028ad38a0bdf4118894231ecbb7200ab28afe095e5de336a8d7bb"},
+    "constants": {"count": 1974, "sha256": "6126e173cc02eb2385ceb7332b349f1522f9dcaad7ba786b0c58ffca3240f9dc"},
     "file_pairs": {"count": 74, "sha256": "1023813dc72dbe4122281d5bae27ac2b7a657dae5904cb5fd603032928199f94"},
     "function_pairs": {"count": 189, "sha256": "11df8bf87b16b535aeddd0c00471f87431236fd0b059484c07f6d5939ace9732"},
     "property_pairs": {"count": 149, "sha256": "8a62616eca6270e3d8899c47cfe8ae93691f16846ed1959e19a762827b6ec185"},
     "constant_pairs": {"count": 681, "sha256": "3484c8096ac8d2832e75f18900c052a19bfb7d92cbc2fa7fdb6137d8fa46ebf6"},
-    "unpaired_files": {"count": 380, "sha256": "6e9cd41c3ee7c16a244e5ef95ff80cb31b27838afbab860416754bc91559adfe"},
-    "unpaired_functions": {"count": 4137, "sha256": "e4abeab38983324cb9716af8d6be4518ca80ce123f13785ee27d2795be306a00"},
+    "unpaired_files": {"count": 382, "sha256": "81e8923060fd20e5a887308d37750f5112f3804f15560833d4c2856f89e2871f"},
+    "unpaired_functions": {"count": 4142, "sha256": "b583ba53e9df860dd4a91e502cbb557bb506ae398c5a8a704770cded8968f206"},
     "unpaired_properties": {"count": 166, "sha256": "280d96f0905fd623dfb66af86c99c3e82409b126a45aaf9e008eb8f6cf04671a"},
-    "unpaired_constants": {"count": 606, "sha256": "d334a29da52e658603db294deb3ff23e9625d682b1914703fc3bb09ebc97ac9a"}
+    "unpaired_constants": {"count": 612, "sha256": "c6c27a5ea84b9b0ac0e13379f68fa5625c95dc5e45652e7658dcdd439d53c777"}
   }
 }
diff --git a/android/app/build.gradle.kts b/android/app/build.gradle.kts
@@ -26,7 +26,7 @@ android {
         applicationId = "com.noop.whoop"
         minSdk = 26
         targetSdk = 34
-        versionCode = 539
+        versionCode = 541
         versionName = "11.8.0"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"

diff --git a/android/app/src/main/java/com/noop/analytics/IntelligenceEngine.kt b/android/app/src/main/java/com/noop/analytics/IntelligenceEngine.kt
@@ -297,8 +297,18 @@ object IntelligenceEngine {
         spo2: List<com.noop.data.Spo2Sample>,
         from: Long,
         to: Long,
+        diag: (String) -> Unit,
     ): Int? {
         if (DeviceBrandCatalog.isOura(owner)) {
+            // Ring 4: the verbatim 0x8b R-ratio records (OURA_SPO2_RPI) when the night has any; otherwise the
+            // firmware 0x6F percentages through the ceiling@100 transform (Gen 3).
+            val ratioRows = runCatching {
+                repo.eventsByKind(owner, com.noop.data.OuraStreamMapping.EVENT_SPO2_RPI, from, to, STREAM_LIMIT)
+            }.getOrDefault(emptyList())
+            OuraSpO2Nightly.summary(sessions, ratioRows)?.let {
+                diag(OuraSpO2Nightly.line(it))
+                return OuraSpO2Nightly.displayMean(it)
+            }
             return AnalyticsEngine.nightlySpo2CeilingMean(sessions, spo2)?.first
         }
         val auxSamples = repo.v18AuxSamples(owner, from, to, STREAM_LIMIT)
@@ -1399,7 +1409,7 @@ object IntelligenceEngine {
                 // bytes of the JVM's 64 KB per-method ceiling, and this block plus the #1575 trace recorders
                 // put the JaCoCo-instrumented size 30 bytes OVER the budget #1524 guards. Neither change
                 // exceeded it alone — only together, which no single PR's CI could see.
-                spo2CandidateMean(repo, owner, res.sleepSessions, spo2, from, to)?.let {
+                spo2CandidateMean(repo, owner, res.sleepSessions, spo2, from, to, ::dayDiag)?.let {
                     spo2CandidateByDay[res.daily.day] = it
                 }
             }

diff --git a/android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt b/android/app/src/main/java/com/noop/analytics/OuraSpO2Nightly.kt
@@ -0,0 +1,55 @@
+package com.noop.analytics
+
+import com.noop.data.EventRow
+import com.noop.data.OuraStreamMapping
+import com.noop.oura.OuraSpO2Ratio
+import kotlin.math.roundToInt
+import org.json.JSONObject
+
+/**
+ * Nightly SpO2 ESTIMATE from the Ring 4's verbatim `0x8b` records (OURA_SPO2_RPI events, OURA_PROTOCOL.md
+ * s6.5.1). A record counts when its anchored time falls inside a detected sleep session; every sample in it is
+ * converted with [OuraSpO2Ratio.percent]. A nightly low / median / mean / high needs no per-second timing, so
+ * the unpinned within-record spacing does not matter here. Diagnostic estimate only: never `spo2Pct`, never
+ * scored. Android-only.
+ */
+internal object OuraSpO2Nightly {
+    /** Samples used, and the night's low / median / mean / high in whole percent (median and mean unrounded). */
+    data class Summary(val samples: Int, val low: Int, val median: Double, val mean: Double, val high: Int)
+
+    /**
+     * Perfusion-index byte marking a held / no-signal sample: in the first Ring 4 capture all 6 of 64 such
+     * samples carried the same R (0.766, ~93 %) while every other sample varied. Inferred, not documented.
+     */
+    const val PI_SATURATED = 0xFF
+
+    fun summary(sessions: List<DetectedSleep>, rows: List<EventRow>): Summary? {
+        if (sessions.isEmpty() || rows.isEmpty()) return null
+        val values = ArrayList<Int>()
+        for (row in rows) {
+            if (row.kind != OuraStreamMapping.EVENT_SPO2_RPI) continue
+            if (sessions.none { row.ts in it.start..it.end }) continue
+            val o = runCatching { JSONObject(row.payloadJSON) }.getOrNull() ?: continue
+            val r = o.optJSONArray("r_x16384") ?: continue
+            val pi = o.optJSONArray("pi") ?: continue
+            if (r.length() != pi.length()) continue
+            for (i in 0 until r.length()) {
+                if (pi.getInt(i) == PI_SATURATED) continue
+                values.add(OuraSpO2Ratio.percent(r.getInt(i) / 16384.0))
+            }
+        }
+        if (values.isEmpty()) return null
+        values.sort()
+        val n = values.size
+        val median = if (n % 2 == 1) values[n / 2].toDouble() else (values[n / 2 - 1] + values[n / 2]) / 2.0
+        return Summary(n, values.first(), median, values.average(), values.last())
+    }
+
+    /** The strap-log line for one night's summary (counts and percentages only). */
+    fun line(s: Summary): String =
+        "spo2 r-pi night samples=${s.samples} low=${s.low} median=${"%.1f".format(java.util.Locale.ROOT, s.median)} " +
+            "mean=${"%.1f".format(java.util.Locale.ROOT, s.mean)} high=${s.high} (0x8b estimate, not scored)"
+
+    /** The whole-percent value the SpO2 estimate tile shows. */
+    fun displayMean(s: Summary): Int = s.mean.roundToInt()
+}