fix(kernel,server,tui,inference): generic resource gauge + F-002/F-003/F-004

- generic SystemResourceProbe: owner-agnostic /proc/meminfo system RAM
  overlaid on the vendor GPU probe, wired on both managed and static paths
  so the VRAM/GPU/RAM gauge renders with an external llama-server (was dormant)
- F-002: classify provider 4xx (e.g. llama.cpp 400) as terminal, not retryable
  (except 408/429); stops retrying deterministic request failures to exhaustion
- F-003: FileSystemPromptLoader expands leading ~ / ~/ to user home
- F-004: map InferenceFailedEvent + RetryAttemptedEvent to new
  ServerMessage.InferenceFailed / RetryAttempted, decoded+rendered in tui-go;
  ArtifactContentStoredEvent explicitly mapped to null (internal, no warn)
- tests: tilde expansion, SystemResourceProbe (static/managed/fail-soft)

apps/server/src/main/kotlin/com/correx/apps/server/Main.kt

@@ -74,6 +74,7 @@ import com.correx.infrastructure.inference.commons.ManagedInferenceRouter
 import com.correx.infrastructure.inference.commons.AmdResourceProbe
 import com.correx.infrastructure.inference.commons.NvidiaResourceProbe
 import com.correx.infrastructure.inference.commons.ResourceProbe
+import com.correx.infrastructure.inference.commons.SystemResourceProbe
 import com.correx.infrastructure.inference.commons.UnavailableProbe
 import com.correx.core.inference.InferenceProvider
 import com.correx.infrastructure.inference.llama.cpp.LlamaCppInferenceProvider
@@ -119,8 +120,10 @@ fun main() {
     val inferenceRouter: InferenceRouter
     // Non-null only on the managed path; backs manual model swap/pin from clients.
     var modelSwapper: ManagedInferenceRouter? = null
-    // Live GPU/RAM gauge; NVIDIA-backed on the managed path when nvidia-smi is present, else unavailable.
-    var resourceProbe: ResourceProbe = UnavailableProbe
+    // Live GPU/RAM gauge. The managed pid lets the GPU probe also report the model's process RSS;
+    // it stays null on the static path. System RAM (overlaid below) is owner-agnostic, so the gauge
+    // renders on both paths regardless of whether correx manages the model process.
+    var managedPidSupplier: () -> Long? = { null }
 
     if (correxConfig.models.isNotEmpty()) {
         val settings = correxConfig.modelsSettings
@@ -146,13 +149,7 @@ fun main() {
         val managedRouter = ManagedInferenceRouter(modelManager, descriptors, targetModelConfig.id)
         inferenceRouter = managedRouter
         modelSwapper = managedRouter
-        resourceProbe = when {
-            NvidiaResourceProbe.isAvailable() ->
-                NvidiaResourceProbe(pidSupplier = { modelManager.currentPid() })
-            AmdResourceProbe.isAvailable() ->
-                AmdResourceProbe(pidSupplier = { modelManager.currentPid() })
-            else -> UnavailableProbe
-        }
+        managedPidSupplier = { modelManager.currentPid() }
         // Shutdown hook to kill the managed llama-server
         Runtime.getRuntime().addShutdownHook(Thread {
             log.info("Shutdown: unloading managed model '{}'", targetModelConfig.id)
@@ -169,6 +166,15 @@ fun main() {
         inferenceRouter = DefaultInferenceRouter(infraRegistry, FirstAvailableRoutingStrategy())
     }
 
+    // Build the resource gauge for whichever GPU vendor is present (pid-less GPU/VRAM reads work on
+    // both paths), then overlay owner-agnostic system RAM so the gauge always renders (F-001 gauge).
+    val gpuProbe: ResourceProbe = when {
+        NvidiaResourceProbe.isAvailable() -> NvidiaResourceProbe(pidSupplier = managedPidSupplier)
+        AmdResourceProbe.isAvailable() -> AmdResourceProbe(pidSupplier = managedPidSupplier)
+        else -> UnavailableProbe
+    }
+    val resourceProbe: ResourceProbe = SystemResourceProbe(gpuProbe)
+
     val modelId = firstProvider.id.value
     logModelInfo(modelId, infraRegistry)
 

apps/server/src/main/kotlin/com/correx/apps/server/bridge/DomainEventMapper.kt

@@ -8,14 +8,17 @@ import com.correx.apps.server.protocol.toDto
 import com.correx.core.artifactstore.ArtifactStore
 import com.correx.core.events.events.ApprovalDecisionResolvedEvent
 import com.correx.core.events.events.ApprovalRequestedEvent
+import com.correx.core.events.events.ArtifactContentStoredEvent
 import com.correx.core.events.events.ArtifactCreatedEvent
 import com.correx.core.events.events.ChatSessionStartedEvent
 import com.correx.core.events.events.ChatTurnEvent
 import com.correx.core.events.events.InferenceCompletedEvent
 import com.correx.core.events.events.SessionWorkspaceBoundEvent
 import com.correx.core.events.events.WorkflowStartedEvent
+import com.correx.core.events.events.InferenceFailedEvent
 import com.correx.core.events.events.InferenceStartedEvent
 import com.correx.core.events.events.InferenceTimeoutEvent
+import com.correx.core.events.events.RetryAttemptedEvent
 import com.correx.core.events.events.ModelLoadedEvent
 import com.correx.core.events.events.ModelUnloadedEvent
 import com.correx.core.events.events.OrchestrationPausedEvent
@@ -149,6 +152,22 @@ suspend fun domainEventToServerMessage(
             sequence = seq,
             sessionSequence = sessionSequence,
         )
+        is InferenceFailedEvent -> ServerMessage.InferenceFailed(
+            sessionId = p.sessionId,
+            stageId = p.stageId,
+            reason = p.reason,
+            sequence = seq,
+            sessionSequence = sessionSequence,
+        )
+        is RetryAttemptedEvent -> ServerMessage.RetryAttempted(
+            sessionId = p.sessionId,
+            stageId = p.stageId,
+            attemptNumber = p.attemptNumber,
+            maxAttempts = p.maxAttempts,
+            failureReason = p.failureReason,
+            sequence = seq,
+            sessionSequence = sessionSequence,
+        )
 
         is ToolInvocationRequestedEvent -> ServerMessage.ToolStarted(
             sessionId = p.sessionId,
@@ -232,6 +251,9 @@ suspend fun domainEventToServerMessage(
             providerId = p.providerId.value,
             loaded = false,
         )
+        // Internal slot→CAS-hash bookkeeping (F-007 durable bridge); no operator-facing surface.
+        is ArtifactContentStoredEvent -> null
+
         else -> {
             log.debug(
                 "DomainEventMapper: unmapped payload type={} sessionId={} sequence={}",

apps/server/src/main/kotlin/com/correx/apps/server/protocol/ServerMessage.kt

@@ -191,6 +191,28 @@ sealed interface ServerMessage {
         override val sessionSequence: Long,
     ) : ServerMessage, SessionMessage
 
+    @Serializable
+    @SerialName("inference.failed")
+    data class InferenceFailed(
+        val sessionId: SessionId,
+        val stageId: StageId,
+        val reason: String,
+        override val sequence: Long,
+        override val sessionSequence: Long,
+    ) : ServerMessage, SessionMessage
+
+    @Serializable
+    @SerialName("inference.retry")
+    data class RetryAttempted(
+        val sessionId: SessionId,
+        val stageId: StageId,
+        val attemptNumber: Int,
+        val maxAttempts: Int,
+        val failureReason: String,
+        override val sequence: Long,
+        override val sessionSequence: Long,
+    ) : ServerMessage, SessionMessage
+
     // -- Tool execution --
 
     @Serializable
@@ -336,6 +358,8 @@ sealed interface ServerMessage {
         val gpuMemoryTotalMb: Long?,
         val gpuUtilizationPct: Int?,
         val processRssMb: Long?,
+        val systemRamUsedMb: Long? = null,
+        val systemRamTotalMb: Long? = null,
         override val sequence: Long? = null,
         override val sessionSequence: Long? = null,
     ) : ServerMessage, NonEventMessage

apps/server/src/main/kotlin/com/correx/apps/server/ws/GlobalStreamHandler.kt

@@ -61,6 +61,8 @@ private fun ResourceSnapshot.toResourceStatus(): ServerMessage.ResourceStatus =
         gpuMemoryTotalMb = gpu?.memoryTotalMb,
         gpuUtilizationPct = gpu?.utilizationPct,
         processRssMb = processRssBytes?.let { it / BYTES_PER_MB },
+        systemRamUsedMb = systemRamUsedBytes?.let { it / BYTES_PER_MB },
+        systemRamTotalMb = systemRamTotalBytes?.let { it / BYTES_PER_MB },
     )
 
 class GlobalStreamHandler(private val module: ServerModule) {

apps/tui-go/internal/app/model.go

@@ -183,6 +183,8 @@ type Model struct {
 	gpuTotalMB      *int64
 	gpuUtil         *int
 	ramMB           *int64
+	sysRamUsedMB    *int64
+	sysRamTotalMB   *int64
 
 	// diff / overlay
 	overlay          OverlayKind

apps/tui-go/internal/app/server.go

@@ -3,6 +3,7 @@ package app
 import (
 	"crypto/rand"
 	"encoding/hex"
+	"fmt"
 	"strings"
 	"time"
 
@@ -172,6 +173,16 @@ func (m *Model) applyServer(msg protocol.ServerMessage) {
 			s.Active = false
 			s.addEvent(nowMillis(), "InferenceTimedOut", msg.StageID)
 		}
+	case protocol.TypeInferenceFailed:
+		if s := m.session(msg.SessionID); s != nil {
+			s.Active = false
+			s.addEvent(nowMillis(), "InferenceFailed", msg.StageID+": "+msg.Reason)
+		}
+	case protocol.TypeInferenceRetry:
+		if s := m.session(msg.SessionID); s != nil {
+			s.addEvent(nowMillis(), "RetryAttempted",
+				fmt.Sprintf("%s (%d/%d): %s", msg.StageID, msg.AttemptNumber, msg.MaxAttempts, msg.FailureReason))
+		}
 	case protocol.TypeToolStarted:
 		if s := m.session(msg.SessionID); s != nil {
 			s.Active = true
@@ -274,6 +285,8 @@ func (m *Model) applyServer(msg protocol.ServerMessage) {
 		m.gpuTotalMB = msg.GpuMemoryTotalMb
 		m.gpuUtil = msg.GpuUtilizationPct
 		m.ramMB = msg.ProcessRssMb
+		m.sysRamUsedMB = msg.SystemRamUsedMb
+		m.sysRamTotalMB = msg.SystemRamTotalMb
 	case protocol.TypeArtifactList:
 		m.artifacts = msg.Artifacts
 		m.artifactsFor = msg.SessionID

apps/tui-go/internal/app/view.go

@@ -117,8 +117,11 @@ func (m Model) gaugeText() string {
 	if m.gpuUtil != nil {
 		parts = append(parts, "GPU "+itoa(*m.gpuUtil)+"%")
 	}
+	if m.sysRamUsedMB != nil && m.sysRamTotalMB != nil {
+		parts = append(parts, "RAM "+itoa(int(*m.sysRamUsedMB))+"/"+itoa(int(*m.sysRamTotalMB))+"M")
+	}
 	if m.ramMB != nil {
-		parts = append(parts, "RAM "+itoa(int(*m.ramMB))+"M")
+		parts = append(parts, "proc "+itoa(int(*m.ramMB))+"M")
 	}
 	return strings.Join(parts, " ")
 }

apps/tui-go/internal/protocol/protocol.go

@@ -26,6 +26,8 @@ const (
 	TypeInferenceStarted = "inference.started"
 	TypeInferenceDone    = "inference.completed"
 	TypeInferenceTimeout = "inference.timed_out"
+	TypeInferenceFailed  = "inference.failed"
+	TypeInferenceRetry   = "inference.retry"
 	TypeToolStarted      = "tool.started"
 	TypeToolCompleted    = "tool.completed"
 	TypeToolFailed       = "tool.failed"
@@ -77,6 +79,11 @@ type ServerMessage struct {
 	Outcome       string  `json:"outcome"`       // approval.resolved: APPROVED | REJECTED | AUTO_APPROVED
 	WorkspaceRoot string  `json:"workspaceRoot"` // session.workspace_bound: the bound cwd
 
+	// inference.retry
+	AttemptNumber int    `json:"attemptNumber"`
+	MaxAttempts   int    `json:"maxAttempts"`
+	FailureReason string `json:"failureReason"`
+
 	SteeringEmitted bool  `json:"steeringEmitted"`
 	OccurredAt      int64 `json:"occurredAt"`
 	ElapsedMs       int64 `json:"elapsedMs"`
@@ -99,6 +106,8 @@ type ServerMessage struct {
 	GpuMemoryTotalMb  *int64 `json:"gpuMemoryTotalMb"`
 	GpuUtilizationPct *int   `json:"gpuUtilizationPct"`
 	ProcessRssMb      *int64 `json:"processRssMb"`
+	SystemRamUsedMb   *int64 `json:"systemRamUsedMb"`
+	SystemRamTotalMb  *int64 `json:"systemRamTotalMb"`
 
 	State          *SessionStateDto   `json:"state"`
 	RiskSummary    *RiskSummaryDto    `json:"riskSummary"`
@@ -209,6 +218,7 @@ func (m ServerMessage) IsEventBearing() bool {
 		TypeSessionCompleted, TypeSessionFailed,
 		TypeStageStarted, TypeStageCompleted, TypeStageFailed,
 		TypeInferenceStarted, TypeInferenceDone, TypeInferenceTimeout,
+		TypeInferenceFailed, TypeInferenceRetry,
 		TypeToolStarted, TypeToolCompleted, TypeToolFailed, TypeToolRejected,
 		TypeToolAssessed,
 		TypeApprovalRequired, TypeApprovalResolved, TypeWorkspaceBound, TypeArtifactCreated,

core/kernel/src/main/kotlin/com/correx/core/kernel/orchestration/SessionOrchestrator.kt

@@ -133,6 +133,10 @@ private const val STAGE_COMPLETE_TOOL = "stage_complete"
 private const val OUTPUT_SUMMARY_LIMIT = 500
 private const val REPO_MAP_INJECT_TOP_K = 30
 
+// HTTP statuses that are transient despite being 4xx (F-002 retry classification).
+private const val HTTP_TIMEOUT = 408
+private const val HTTP_TOO_MANY_REQUESTS = 429
+
 @SuppressWarnings(
     "ForbiddenComment",
     "UnusedParameter",
@@ -474,7 +478,8 @@ abstract class SessionOrchestrator(
         }
         return when (inferenceResult) {
             is InferenceResult.Cancelled -> StageExecutionResult.Failure("CANCELLED", retryable = false)
-            is InferenceResult.Failed -> StageExecutionResult.Failure(inferenceResult.reason, retryable = true)
+            is InferenceResult.Failed ->
+                StageExecutionResult.Failure(inferenceResult.reason, retryable = isRetryableFailure(inferenceResult.reason))
             is InferenceResult.Success -> {
                 if (isCancelled(sessionId)) return StageExecutionResult.Failure("CANCELLED", retryable = false)
                 // Capture the LLM-emitted artifact's JSON so transition conditions
@@ -1329,6 +1334,16 @@ abstract class SessionOrchestrator(
         }
     }
 
+    // A provider 4xx client error (e.g. llama.cpp 400 "invalid_request") is a deterministic
+    // request-construction failure — retrying re-sends the identical bad request and exhausts the
+    // budget for nothing (F-002). Treat 4xx as terminal, except 408 (timeout) and 429 (rate-limit)
+    // which are transient. Everything else (network/5xx/unknown) stays retryable.
+    private fun isRetryableFailure(reason: String): Boolean {
+        val status = Regex("""returned\s+(\d{3})""").find(reason)?.groupValues?.get(1)?.toIntOrNull()
+            ?: return true
+        return status !in 400..499 || status == HTTP_TIMEOUT || status == HTTP_TOO_MANY_REQUESTS
+    }
+
     // --- transition helpers ---
 
     internal fun resolveTransition(

infrastructure/inference/commons/src/main/kotlin/com/correx/infrastructure/inference/commons/ResourceProbe.kt

@@ -1,5 +1,8 @@
 package com.correx.infrastructure.inference.commons
 
+import org.slf4j.LoggerFactory
+import java.io.File
+
 /**
  * Whole-device GPU usage at an instant. All fields are device-wide (not per-process) —
  * per-model VRAM attribution is an explicit non-goal.
@@ -11,13 +14,19 @@ data class GpuStatus(
 )
 
 /**
- * A point-in-time reading of local-model resource usage. Both fields are nullable so that
- * "unavailable" is representable without exceptions: [gpu] is null when no GPU probe is present
- * (non-NVIDIA box / `nvidia-smi` absent), [processRssBytes] is null when no model is resident.
+ * A point-in-time reading of local resource usage. All fields are nullable so that "unavailable"
+ * is representable without exceptions: [gpu] is null when no GPU probe is present (non-NVIDIA/AMD
+ * box or the tool is absent), [processRssBytes] is null when no correx-managed model is resident,
+ * and [systemRamUsedBytes]/[systemRamTotalBytes] are null when `/proc/meminfo` can't be read.
+ *
+ * System RAM is **owner-agnostic** — it reflects the whole host regardless of who launched the
+ * model, so the gauge renders even on the static (external `llama-server`) path.
  */
 data class ResourceSnapshot(
     val gpu: GpuStatus?,
     val processRssBytes: Long?,
+    val systemRamUsedBytes: Long? = null,
+    val systemRamTotalBytes: Long? = null,
 ) {
     companion object {
         val UNAVAILABLE = ResourceSnapshot(gpu = null, processRssBytes = null)
@@ -34,7 +43,49 @@ fun interface ResourceProbe {
     fun probe(): ResourceSnapshot
 }
 
-/** Always-unavailable probe — used on non-GPU boxes and the static (unmanaged) provider path. */
+/** Always-unavailable probe — used on non-GPU boxes when even system RAM can't be read. */
 object UnavailableProbe : ResourceProbe {
     override fun probe(): ResourceSnapshot = ResourceSnapshot.UNAVAILABLE
 }
+
+/**
+ * Owner-agnostic composite probe: delegates GPU/process-RSS to a vendor [gpuProbe] (NVIDIA/AMD or
+ * [UnavailableProbe]) and always overlays whole-host system RAM read from `/proc/meminfo`. This is
+ * what makes the gauge render on BOTH the managed and static (external `llama-server`) paths — the
+ * system-RAM read needs no managed pid. The RAM read is injectable for testing.
+ */
+class SystemResourceProbe(
+    private val gpuProbe: ResourceProbe = UnavailableProbe,
+    private val systemRamReader: () -> Pair<Long, Long>? = SystemRam::readUsedTotalBytes,
+) : ResourceProbe {
+    override fun probe(): ResourceSnapshot {
+        val base = gpuProbe.probe()
+        val ram = systemRamReader()
+        return base.copy(
+            systemRamUsedBytes = ram?.first,
+            systemRamTotalBytes = ram?.second,
+        )
+    }
+}
+
+/** Reads whole-host RAM from `/proc/meminfo`. Fails soft to null so a non-Linux host never throws. */
+object SystemRam {
+    private val log = LoggerFactory.getLogger("SystemRam")
+    private const val BYTES_PER_KB = 1024L
+
+    /** Returns (usedBytes, totalBytes) where used = MemTotal − MemAvailable, or null if unreadable. */
+    fun readUsedTotalBytes(): Pair<Long, Long>? = runCatching {
+        val meminfo = File("/proc/meminfo")
+        if (!meminfo.exists()) return null
+        val lines = meminfo.readLines()
+        val total = lines.kbValue("MemTotal:") ?: return null
+        val available = lines.kbValue("MemAvailable:") ?: return null
+        val used = (total - available).coerceAtLeast(0)
+        (used * BYTES_PER_KB) to (total * BYTES_PER_KB)
+    }.onFailure { log.debug("/proc/meminfo read failed: {}", it.message) }.getOrNull()
+
+    // Parses a "Key:   12345 kB" line to its kB value.
+    private fun List<String>.kbValue(key: String): Long? =
+        firstOrNull { it.startsWith(key) }
+            ?.removePrefix(key)?.trim()?.substringBefore(' ')?.toLongOrNull()
+}

infrastructure/workflow/src/main/kotlin/com/correx/infrastructure/workflow/FileSystemPromptLoader.kt

@@ -8,12 +8,21 @@ class FileSystemPromptLoader(
     private val configDir: Path = Path.of(System.getProperty("user.home"), ".config", "correx", "prompts"),
 ) : PromptLoader {
     override fun load(path: String): String {
-        val local = Path.of(path)
+        val expanded = expandTilde(path)
+        val local = Path.of(expanded)
         if (local.exists()) return local.readText()
 
-        val fromConfig = configDir.resolve(path)
+        val fromConfig = configDir.resolve(expanded)
         if (fromConfig.exists()) return fromConfig.readText()
 
         throw PromptNotFoundException("Prompt not found: $path (searched: $local, $fromConfig)")
     }
+
+    // Expand a leading `~` / `~/...` to the user home so a config-supplied home path resolves
+    // instead of being concatenated literally onto [configDir] (F-003).
+    private fun expandTilde(path: String): String = when {
+        path == "~" -> System.getProperty("user.home")
+        path.startsWith("~/") -> System.getProperty("user.home") + path.substring(1)
+        else -> path
+    }
 }

infrastructure/workflow/src/test/kotlin/com/correx/infrastructure/workflow/FileSystemPromptLoaderTest.kt

@@ -33,6 +33,19 @@ class FileSystemPromptLoaderTest {
         assertContains(ex.message!!, configDir.toString())
     }
 
+    @Test
+    fun `expands leading tilde to user home (F-003)`() {
+        val home = System.getProperty("user.home")
+        val rel = "correx-tilde-${System.nanoTime()}.md"
+        val file = java.nio.file.Path.of(home, rel).also { it.writeText("home prompt") }
+        try {
+            val loader = FileSystemPromptLoader(configDir = Files.createTempDirectory("unused"))
+            assertEquals("home prompt", loader.load("~/$rel"))
+        } finally {
+            Files.deleteIfExists(file)
+        }
+    }
+
     @Test
     fun `local path takes precedence over configDir`() {
         val localFile = Files.createTempFile("prompt", ".md").also { it.writeText("local") }

qa/audit-report-2026-06-08.md

@@ -94,7 +94,9 @@ repo `docs/schemas/` were stale relative to live — a clean-checkout reproducti
   identical 400s within ~80ms, then `WorkflowFailedEvent retryExhausted=true`.
 - **suspected cause:** retry classifier treats all provider failures as retryable. A 400
   `invalid_request_error` is deterministic request-construction failure → should be terminal.
-- **status:** confirmed
+- **status:** FIXED (2026-06-10) — `SessionOrchestrator.isRetryableFailure` parses the
+  provider status from the failure reason; 4xx is terminal (except 408/429), 5xx/network/
+  unknown stay retryable. So a 400 now fails fast instead of burning the retry budget.
 
 ### F-003 — `~` not expanded in default_system prompt path
 - **subsystem:** core/kernel (prompt loading) / core/config
@@ -103,7 +105,8 @@ repo `docs/schemas/` were stale relative to live — a clean-checkout reproducti
   Prompt not found (searched: .../prompts/~/.config/correx/prompts/default_system.md)` —
   tilde concatenated literally onto the config dir. Logged ERROR on every attempt.
   Non-fatal (run proceeds) but noisy + the default system prompt is silently absent.
-- **status:** confirmed
+- **status:** FIXED (2026-06-10) — `FileSystemPromptLoader.expandTilde` resolves a leading
+  `~`/`~/` to the user home before lookup (unit-tested).
 
 ### F-005 — file_read jails relative paths against process cwd, not the workspace
 - **invariant/contract:** functional (tool jailing) / two-plane consistency (#9)
@@ -192,9 +195,10 @@ repo `docs/schemas/` were stale relative to live — a clean-checkout reproducti
 - **evidence:** `DomainEventMapper: unmapped payload type=InferenceFailedEvent` and
   `=RetryAttemptedEvent` repeated. Operator sees failure only via router narration, not a
   structured failure/retry surface in the TUI.
-- **status:** confirmed
-- **note:** `ArtifactContentStoredEvent` is also unmapped (`DomainEventMapper: unmapped
-  payload type=ArtifactContentStoredEvent`) — same class of gap, new event added this session.
+- **status:** FIXED (2026-06-10) — new `ServerMessage.InferenceFailed` /
+  `RetryAttempted` variants; `DomainEventMapper` arms map `InferenceFailedEvent` /
+  `RetryAttemptedEvent`; tui-go decodes + renders them as session events. The internal
+  `ArtifactContentStoredEvent` is now explicitly mapped to null (no operator surface, no warn).
 
 ### F-008 — stage `token_budget` not propagated to provider `max_tokens` → truncation
 - **invariant/contract:** functional (workflows run end-to-end) / #7 (validatable output)
@@ -326,8 +330,9 @@ repo `docs/schemas/` were stale relative to live — a clean-checkout reproducti
   contents) were cut off mid-generation, burning all retries → `did not produce patch`.
 - **root cause:** `OrchestrationConfig.stageTimeoutMs` defaults to `60_000L` and is hardcoded
   in `Main` (`defaultOrchestrationConfig`) with no config wiring.
-- **status:** PARTIAL — raised to `180_000L` in `Main`. Should be surfaced as a config knob
-  (TODO left at the patch site).
+- **status:** FIXED — now a real config knob `orchestration.stage_timeout_ms`
+  (`CorrexConfig.OrchestrationKnobs`, default 180s), parsed by `ConfigLoader`, written by
+  `CorrexConfigWriter`, live-editable via `EditableConfig`, wired in `Main.kt`.
 
 ### F-017 (observation, not a correx defect) — local model does not reliably issue write tools
 - **invariant/contract:** n/a (model capability)

testing/contracts/src/test/kotlin/com/correx/testing/contracts/model/inference/SystemResourceProbeTest.kt

@@ -0,0 +1,55 @@
+package com.correx.testing.contracts.model.inference
+
+import com.correx.infrastructure.inference.commons.GpuStatus
+import com.correx.infrastructure.inference.commons.ResourceProbe
+import com.correx.infrastructure.inference.commons.ResourceSnapshot
+import com.correx.infrastructure.inference.commons.SystemResourceProbe
+import com.correx.infrastructure.inference.commons.UnavailableProbe
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Test
+
+class SystemResourceProbeTest {
+
+    private val bytesPerKb = 1024L
+
+    @Test
+    fun `overlays system RAM onto an unavailable GPU probe (static path, F-001 gauge)`() {
+        val probe = SystemResourceProbe(
+            gpuProbe = UnavailableProbe,
+            systemRamReader = { (4L * bytesPerKb) to (16L * bytesPerKb) },
+        )
+        val snap = probe.probe()
+        assertNull(snap.gpu) // no managed model / no GPU, yet RAM still renders
+        assertNull(snap.processRssBytes)
+        assertEquals(4L * bytesPerKb, snap.systemRamUsedBytes)
+        assertEquals(16L * bytesPerKb, snap.systemRamTotalBytes)
+    }
+
+    @Test
+    fun `preserves the delegate GPU and process RSS while adding system RAM (managed path)`() {
+        val gpuDelegate = ResourceProbe {
+            ResourceSnapshot(
+                gpu = GpuStatus(memoryUsedMb = 2048, memoryTotalMb = 8192, utilizationPct = 50),
+                processRssBytes = 999L,
+            )
+        }
+        val probe = SystemResourceProbe(
+            gpuProbe = gpuDelegate,
+            systemRamReader = { 100L to 200L },
+        )
+        val snap = probe.probe()
+        assertEquals(2048L, snap.gpu?.memoryUsedMb)
+        assertEquals(999L, snap.processRssBytes)
+        assertEquals(100L, snap.systemRamUsedBytes)
+        assertEquals(200L, snap.systemRamTotalBytes)
+    }
+
+    @Test
+    fun `fails soft to null system RAM when the reader is unavailable`() {
+        val probe = SystemResourceProbe(gpuProbe = UnavailableProbe, systemRamReader = { null })
+        val snap = probe.probe()
+        assertNull(snap.systemRamUsedBytes)
+        assertNull(snap.systemRamTotalBytes)
+    }
+}