diff --git a/Packages/OsaurusCore/Managers/Model/ModelManager.swift b/Packages/OsaurusCore/Managers/Model/ModelManager.swift
index c87d515f6..dc6595695 100644
--- a/Packages/OsaurusCore/Managers/Model/ModelManager.swift
+++ b/Packages/OsaurusCore/Managers/Model/ModelManager.swift
@@ -188,7 +188,27 @@ final class ModelManager: NSObject, ObservableObject {
 
         // Pull the OsaurusAI HF org listing once on launch so newly published
         // models surface in the Recommended tab without requiring a code push.
-        Task { [weak self] in await self?.loadOsaurusAIOrgModels() }
+        //
+        // The unit-test runner constructs `ModelManager()` repeatedly to drive
+        // `applyOsaurusOrgFetch` directly. If the launch-time HF fetch races
+        // with those test calls, whichever finishes last wins and the merge
+        // result is non-deterministic — that's the regression class behind
+        // `ModelManagerSuggestedTests/applyOsaurusOrgFetch_*` flaking in CI.
+        // Skip the background fetch under XCTest; production launches still
+        // get it because `XCTestConfigurationFilePath` is only set inside
+        // a test host.
+        if !Self.isRunningInTestEnvironment {
+            Task { [weak self] in await self?.loadOsaurusAIOrgModels() }
+        }
+    }
+
+    /// True when the current process was launched by xctest. Used to gate
+    /// network-touching launch-time side effects so tests can drive the
+    /// affected code paths deterministically.
+    nonisolated private static var isRunningInTestEnvironment: Bool {
+        ProcessInfo.processInfo.environment["XCTestConfigurationFilePath"] != nil
+            || ProcessInfo.processInfo.environment["XCTestBundlePath"] != nil
+            || ProcessInfo.processInfo.environment["XCTestSessionIdentifier"] != nil
     }
 
     // MARK: - Public Methods
diff --git a/Packages/OsaurusCore/Services/Memory/MemoryContextAssembler.swift b/Packages/OsaurusCore/Services/Memory/MemoryContextAssembler.swift
index 71844912f..623054554 100644
--- a/Packages/OsaurusCore/Services/Memory/MemoryContextAssembler.swift
+++ b/Packages/OsaurusCore/Services/Memory/MemoryContextAssembler.swift
@@ -116,15 +116,40 @@ public actor MemoryContextAssembler {
         return context
     }
 
-    /// Invalidate cached context for a specific agent.
+    /// Invalidate cached context for a specific agent, or the entire cache
+    /// when `agentId` is nil.
+    ///
+    /// Cache entries are keyed by `(agentId, toolsAvailable)` (see `cacheKey`).
+    /// Removing only the bare `agentId` would leave stale `tools=0`/`tools=1`
+    /// snapshots in place for up to `cacheTTL` seconds, defeating callers like
+    /// `ChatWindowManager` that invalidate after user-visible memory edits.
+    /// Drop both partitions for the given agent.
     public func invalidateCache(agentId: String? = nil) {
         if let agentId {
-            cache.removeValue(forKey: agentId)
+            cache.removeValue(forKey: Self.cacheKey(agentId: agentId, toolsAvailable: true))
+            cache.removeValue(forKey: Self.cacheKey(agentId: agentId, toolsAvailable: false))
         } else {
             cache.removeAll()
         }
     }
 
+    /// Test-only helper: returns true if a non-expired cache entry exists for
+    /// the given `(agentId, toolsAvailable)` pair. Used to verify that
+    /// `invalidateCache(agentId:)` evicts both partitions.
+    internal func _hasCachedEntry(agentId: String, toolsAvailable: Bool) -> Bool {
+        guard let entry = cache[Self.cacheKey(agentId: agentId, toolsAvailable: toolsAvailable)] else {
+            return false
+        }
+        return Date().timeIntervalSince(entry.timestamp) < Self.cacheTTL
+    }
+
+    /// Test-only helper: seeds a cache entry for the given agent/partition.
+    /// Avoids needing a fully wired `MemoryDatabase` for cache-eviction tests.
+    internal func _seedCache(agentId: String, toolsAvailable: Bool, context: String = "seeded") {
+        cache[Self.cacheKey(agentId: agentId, toolsAvailable: toolsAvailable)] =
+            CacheEntry(context: context, timestamp: Date())
+    }
+
     private func buildContext(
         agentId: String,
         config: MemoryConfiguration,
diff --git a/Packages/OsaurusCore/Tests/Memory/MemoryTests.swift b/Packages/OsaurusCore/Tests/Memory/MemoryTests.swift
index 7b4c0df08..2e50f1530 100644
--- a/Packages/OsaurusCore/Tests/Memory/MemoryTests.swift
+++ b/Packages/OsaurusCore/Tests/Memory/MemoryTests.swift
@@ -243,6 +243,55 @@ struct MemoryContextAssemblerTests {
         )
         #expect(baseContext == queryContext)
     }
+
+    /// Regression test for a cache-key mismatch where `invalidateCache(agentId:)`
+    /// removed entries keyed solely on `agentId` while the cache was actually
+    /// keyed on `(agentId, toolsAvailable)`. The bug let stale 10-second
+    /// snapshots survive user-visible memory edits, contradicting the
+    /// invalidation contract that callers like `ChatWindowManager` rely on.
+    @Test func invalidateCacheEvictsBothToolsPartitions() async {
+        let assembler = MemoryContextAssembler.shared
+        let agentId = "cache-test-\(UUID().uuidString)"
+
+        await assembler._seedCache(agentId: agentId, toolsAvailable: true)
+        await assembler._seedCache(agentId: agentId, toolsAvailable: false)
+
+        let beforeWithTools = await assembler._hasCachedEntry(
+            agentId: agentId, toolsAvailable: true)
+        let beforeChatOnly = await assembler._hasCachedEntry(
+            agentId: agentId, toolsAvailable: false)
+        #expect(beforeWithTools)
+        #expect(beforeChatOnly)
+
+        await assembler.invalidateCache(agentId: agentId)
+
+        let afterWithTools = await assembler._hasCachedEntry(
+            agentId: agentId, toolsAvailable: true)
+        let afterChatOnly = await assembler._hasCachedEntry(
+            agentId: agentId, toolsAvailable: false)
+        #expect(!afterWithTools)
+        #expect(!afterChatOnly)
+    }
+
+    @Test func invalidateCacheScopedToAgent() async {
+        let assembler = MemoryContextAssembler.shared
+        let target = "target-\(UUID().uuidString)"
+        let other = "other-\(UUID().uuidString)"
+
+        await assembler._seedCache(agentId: target, toolsAvailable: true)
+        await assembler._seedCache(agentId: other, toolsAvailable: true)
+
+        await assembler.invalidateCache(agentId: target)
+
+        let targetStillCached = await assembler._hasCachedEntry(
+            agentId: target, toolsAvailable: true)
+        let otherStillCached = await assembler._hasCachedEntry(
+            agentId: other, toolsAvailable: true)
+        #expect(!targetStillCached)
+        #expect(otherStillCached)
+
+        await assembler.invalidateCache(agentId: other)
+    }
 }
 
 struct MemoryDatabaseTests {