fix(desktop): scope memory graph cache by profile

Ensure the Memory Graph cannot show stale data after switching profiles, and tighten the graph backend's profile-safe timestamp handling.

agent/learning_graph.py

@@ -16,12 +16,14 @@ Run as a module to print edge-density stats against real data:
 from __future__ import annotations
 
 import json
-import os
 import re
 from dataclasses import dataclass, field
+from datetime import datetime, timezone
 from pathlib import Path
 from typing import Any, Optional
 
+from hermes_constants import get_hermes_home
+
 
 @dataclass
 class SkillNode:
@@ -77,7 +79,7 @@ def _load_usage() -> dict[str, dict[str, Any]]:
 
         return load_usage()
     except Exception:
-        path = Path(os.path.expanduser("~/.hermes/skills/.usage.json"))
+        path = get_hermes_home() / "skills" / ".usage.json"
         try:
             return json.loads(path.read_text(encoding="utf-8"))
         except Exception:
@@ -91,11 +93,27 @@ def _to_int_ts(value: Any) -> Optional[int]:
         if isinstance(value, (int, float)):
             return int(value)
         s = str(value).strip()
-        return int(float(s)) if s else None
+        if not s:
+            return None
+        try:
+            return int(float(s))
+        except ValueError:
+            parsed = datetime.fromisoformat(s.replace("Z", "+00:00"))
+            if parsed.tzinfo is None:
+                parsed = parsed.replace(tzinfo=timezone.utc)
+            return int(parsed.timestamp())
     except Exception:
         return None
 
 
+def _usage_timestamp(rec: dict[str, Any]) -> Optional[int]:
+    for key in ("last_activity_at", "last_used_at", "last_viewed_at", "last_patched_at", "created_at"):
+        ts = _to_int_ts(rec.get(key))
+        if ts is not None:
+            return ts
+    return None
+
+
 def build_skill_nodes(skill_roots: list[tuple[str, Path]]) -> dict[str, SkillNode]:
     usage = _load_usage()
     nodes: dict[str, SkillNode] = {}
@@ -111,7 +129,7 @@ def build_skill_nodes(skill_roots: list[tuple[str, Path]]) -> dict[str, SkillNod
         if not name or name in nodes:
             continue
         rec = usage.get(name, {})
-        last_activity = _to_int_ts(rec.get("last_activity_at"))
+        last_activity = _usage_timestamp(rec)
         file_ts = _to_int_ts(skill_md.stat().st_mtime)
         nodes[name] = SkillNode(
             name=name,
@@ -134,7 +152,8 @@ def build_edges(nodes: dict[str, SkillNode]) -> list[tuple[str, str]]:
     for node in nodes.values():
         for target in node.related:
             if target in nodes and target != node.name:
-                key = tuple(sorted((node.name, target)))
+                a, b = sorted((node.name, target))
+                key = (a, b)
                 if key not in seen:
                     seen.add(key)
                     edges.append(key)
@@ -169,13 +188,7 @@ def _memory_cards() -> list[dict[str, Any]]:
     ``MEMORY.md`` / ``USER.md`` are prose split on bare ``§`` separators; each
     chunk becomes one card. Every chunk is surfaced — the graph shows everything.
     """
-    try:
-        from hermes_constants import get_hermes_home
-
-        base = get_hermes_home() / "memories"
-    except Exception:
-        base = Path(os.path.expanduser("~/.hermes/memories"))
-
+    base = get_hermes_home() / "memories"
     cards: list[dict[str, Any]] = []
     for fname, source in (("MEMORY.md", "memory"), ("USER.md", "profile")):
         path = base / fname
@@ -203,7 +216,7 @@ def _tokenize(text: str) -> set[str]:
     return {t for t in re.split(r"[^a-z0-9]+", text.lower()) if len(t) >= 3}
 
 
-def _memory_skill_edges(memory_cards: list[dict[str, str]], skills: list[SkillNode]) -> list[tuple[str, str]]:
+def _memory_skill_edges(memory_cards: list[dict[str, Any]], skills: list[SkillNode]) -> list[tuple[str, str]]:
     edges: list[tuple[str, str]] = []
     skill_meta = [(s, _tokenize(s.name), s.name.lower()) for s in skills]
     for idx, card in enumerate(memory_cards):
@@ -226,12 +239,7 @@ def _memory_skill_edges(memory_cards: list[dict[str, str]], skills: list[SkillNo
 
 def _skill_roots() -> list[tuple[str, Path]]:
     repo = Path(__file__).resolve().parent.parent
-    try:
-        from hermes_constants import get_hermes_home
-
-        home_skills = get_hermes_home() / "skills"
-    except Exception:
-        home_skills = Path(os.path.expanduser("~/.hermes/skills"))
+    home_skills = get_hermes_home() / "skills"
     return [("base", repo / "skills"), ("profile", home_skills)]
 
 

apps/desktop/src/store/profile.test.ts

@@ -7,6 +7,7 @@ import type { HermesConnection } from '@/global'
 // the REST query client must not run for real in a unit test.
 const ensureGatewayForProfile = vi.fn(async () => undefined)
 const $gateway = atom<unknown>({ id: 'live-socket' })
+const resetStarmapGraph = vi.fn()
 
 vi.mock('@/store/gateway', () => ({ $gateway, ensureGatewayForProfile }))
 vi.mock('@/hermes', () => ({
@@ -14,9 +15,11 @@ vi.mock('@/hermes', () => ({
   setApiRequestProfile: vi.fn()
 }))
 vi.mock('@/lib/query-client', () => ({ queryClient: { invalidateQueries: vi.fn() } }))
+vi.mock('@/store/starmap', () => ({ resetStarmapGraph }))
 
 const { $activeGatewayProfile, ensureGatewayProfile } = await import('./profile')
 const { $connection } = await import('./session')
+const { queryClient } = await import('@/lib/query-client')
 
 const remoteConn = (over: Partial<HermesConnection> = {}): HermesConnection =>
   ({ baseUrl: 'https://hermes-roy.tail.ts.net', mode: 'remote', profile: 'vps-remote', ...over }) as HermesConnection
@@ -33,6 +36,8 @@ beforeEach(() => {
   $activeGatewayProfile.set('default')
   $connection.set(localConn())
   vi.stubGlobal('window', { hermesDesktop: { getConnection } })
+  vi.mocked(queryClient.invalidateQueries).mockClear()
+  resetStarmapGraph.mockClear()
 })
 
 afterEach(() => {
@@ -87,3 +92,12 @@ describe('ensureGatewayProfile → $connection sync (#46651)', () => {
     expect($connection.get()?.mode).toBe('remote')
   })
 })
+
+describe('profile-scoped cache invalidation', () => {
+  it('drops the memory graph cache when the active gateway profile changes', () => {
+    $activeGatewayProfile.set('coder')
+
+    expect(queryClient.invalidateQueries).toHaveBeenCalled()
+    expect(resetStarmapGraph).toHaveBeenCalledTimes(1)
+  })
+})

apps/desktop/src/store/profile.ts

@@ -13,6 +13,7 @@ import {
 } from '@/lib/storage'
 import { $gateway, ensureGatewayForProfile } from '@/store/gateway'
 import { setConnection } from '@/store/session'
+import { resetStarmapGraph } from '@/store/starmap'
 import type { ProfileInfo } from '@/types/hermes'
 
 // Canonical key for a profile: trimmed, empty → "default". Used everywhere we
@@ -168,6 +169,7 @@ $activeGatewayProfile.subscribe(value => {
   if (_lastRoutedProfile !== null && _lastRoutedProfile !== key) {
     // Profile-scoped settings + the unified session list are now stale.
     void queryClient.invalidateQueries()
+    resetStarmapGraph()
   }
 
   _lastRoutedProfile = key

package-lock.json

@@ -1786,6 +1786,72 @@
         "node": ">= 10.0.0"
       }
     },
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+      "dev": true,
+      "license": "BSD-2-Clause",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "cross-dirname": "^0.1.0",
+        "debug": "^4.3.4",
+        "fs-extra": "^11.1.1",
+        "minimist": "^1.2.8",
+        "postject": "^1.0.0-alpha.6"
+      },
+      "bin": {
+        "electron-windows-sign": "bin/electron-windows-sign.js"
+      },
+      "engines": {
+        "node": ">=14.14"
+      }
+    },
+    "node_modules/@electron/windows-sign/node_modules/fs-extra": {
+      "version": "11.3.5",
+      "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-11.3.5.tgz",
+      "integrity": "sha512-eKpRKAovdpZtR1WopLHxlBWvAgPny3c4gX1G5Jhwmmw4XJj0ifSD5qB5TOo8hmA0wlRKDAOAhEE1yVPgs6Fgcg==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "graceful-fs": "^4.2.0",
+        "jsonfile": "^6.0.1",
+        "universalify": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=14.14"
+      }
+    },
+    "node_modules/@electron/windows-sign/node_modules/jsonfile": {
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+      "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-6.2.1.tgz",
+      "integrity": "sha512-zwOTdL3rFQ/lRdBnntKVOX6k5cKJwEc1HdilT71BWEu7J41gXIB2MRp+vxduPSwZJPWBxEzv4yH1wYLJGUHX4Q==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
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+      "dependencies": {
+        "universalify": "^2.0.0"
+      },
+      "optionalDependencies": {
+        "graceful-fs": "^4.1.6"
+      }
+    },
+    "node_modules/@electron/windows-sign/node_modules/universalify": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/universalify/-/universalify-2.0.1.tgz",
+      "integrity": "sha512-gptHNQghINnc/vTGIk0SOFGFNXw7JVrlRUtConJRlvaw6DuX0wO5Jeko9sWrMBhh+PsYAZ7oXAiOnf/UKogyiw==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
+      "peer": true,
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+      }
+    },
     "node_modules/@emnapi/core": {
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@@ -1824,6 +1890,448 @@
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       "license": "MIT"
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+      "cpu": [
+        "ppc64"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "aix"
+      ],
+      "peer": true,
+      "engines": {
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+      }
+    },
+    "node_modules/@esbuild/android-arm": {
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+      "resolved": "https://registry.npmjs.org/@esbuild/android-arm/-/android-arm-0.28.1.tgz",
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+      "cpu": [
+        "arm"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
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+      "engines": {
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+    "node_modules/@esbuild/android-arm64": {
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+      "cpu": [
+        "x64"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "netbsd"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/@esbuild/openbsd-arm64": {
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+        "arm64"
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+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "openbsd"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
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+      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-x64/-/openbsd-x64-0.28.1.tgz",
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+      "optional": true,
+      "os": [
+        "openbsd"
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+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/@esbuild/openharmony-arm64": {
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+      "resolved": "https://registry.npmjs.org/@esbuild/openharmony-arm64/-/openharmony-arm64-0.28.1.tgz",
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+        "arm64"
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+      "os": [
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+      ],
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+      "cpu": [
+        "x64"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "sunos"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/@esbuild/win32-arm64": {
+      "version": "0.28.1",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-arm64/-/win32-arm64-0.28.1.tgz",
+      "integrity": "sha512-lCv9eK/H6ZJWbE7bh2nw54CZ9M2nupBxJcTsdk/QQnWkdSjKGuxmmH8/GWrlT1eMmZfn4dGcCjRte397WqfQXA==",
+      "cpu": [
+        "arm64"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "win32"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/@esbuild/win32-ia32": {
+      "version": "0.28.1",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-ia32/-/win32-ia32-0.28.1.tgz",
+      "integrity": "sha512-zvb/mB2bSCoJOpoCBgYKKpX6YM6mJBlBUVUtVj41DlZJVEB6/0CKlRYxP5wWl1C1ILiCoAU5wZZ4q1P3qeS6Eg==",
+      "cpu": [
+        "ia32"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "win32"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/@esbuild/win32-x64": {
+      "version": "0.28.1",
+      "resolved": "https://registry.npmjs.org/@esbuild/win32-x64/-/win32-x64-0.28.1.tgz",
+      "integrity": "sha512-bm4Mowrv+GXMlpWX++EcXw/iLyd1o3+bJkC2DkWXYVvgZCqD/bSj9ctZeAMC3cIxgjRVR2Dufaiu4YPxr5gW1A==",
+      "cpu": [
+        "x64"
+      ],
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "win32"
+      ],
+      "peer": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
     "node_modules/@eslint-community/eslint-utils": {
       "version": "4.9.1",
       "resolved": "https://registry.npmjs.org/@eslint-community/eslint-utils/-/eslint-utils-4.9.1.tgz",
@@ -7930,6 +8438,15 @@
       "integrity": "sha512-VQ2MBenTq1fWZUH9DJNGti7kKv6EeAuYr3cLwxUWhIu1baTaXh4Ib5W2CqHVqib4/MqbYGJqiL3Zb8GJZr3l4g==",
       "license": "MIT"
     },
+    "node_modules/cross-dirname": {
+      "version": "0.1.0",
+      "resolved": "https://registry.npmjs.org/cross-dirname/-/cross-dirname-0.1.0.tgz",
+      "integrity": "sha512-+R08/oI0nl3vfPcqftZRpytksBXDzOUveBq/NBVx0sUp1axwzPQrKinNx5yd5sxPu8j1wIy8AfnVQ+5eFdha6Q==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
+      "peer": true
+    },
     "node_modules/cross-env": {
       "version": "10.1.0",
       "resolved": "https://registry.npmjs.org/cross-env/-/cross-env-10.1.0.tgz",
@@ -15044,6 +15561,36 @@
         "node": "^10 || ^12 || ^13.7 || ^14 || >=15.0.1"
       }
     },
+    "node_modules/postject": {
+      "version": "1.0.0-alpha.6",
+      "resolved": "https://registry.npmjs.org/postject/-/postject-1.0.0-alpha.6.tgz",
+      "integrity": "sha512-b9Eb8h2eVqNE8edvKdwqkrY6O7kAwmI8kcnBv1NScolYJbo59XUF0noFq+lxbC1yN20bmC0WBEbDC5H/7ASb0A==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "commander": "^9.4.0"
+      },
+      "bin": {
+        "postject": "dist/cli.js"
+      },
+      "engines": {
+        "node": ">=14.0.0"
+      }
+    },
+    "node_modules/postject/node_modules/commander": {
+      "version": "9.5.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-9.5.0.tgz",
+      "integrity": "sha512-KRs7WVDKg86PWiuAqhDrAQnTXZKraVcCc6vFdL14qrZ/DcWwuRo7VoiYXalXO7S5GKpqYiVEwCbgFDfxNHKJBQ==",
+      "dev": true,
+      "license": "MIT",
+      "optional": true,
+      "peer": true,
+      "engines": {
+        "node": "^12.20.0 || >=14"
+      }
+    },
     "node_modules/prelude-ls": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.2.1.tgz",

tests/agent/test_learning_graph.py

@@ -43,6 +43,29 @@ def test_density_stats_count_isolated_nodes():
     assert stats["isolated_pct"] == round(100 / 3, 1)
 
 
+def test_skill_node_timestamp_uses_iso_usage_activity(tmp_path, monkeypatch):
+    skill_dir = tmp_path / "skills" / "dev" / "iso-skill"
+    skill_dir.mkdir(parents=True)
+    skill_md = skill_dir / "SKILL.md"
+    skill_md.write_text("---\nname: iso-skill\ncategory: dev\n---\n# ISO\n", encoding="utf-8")
+
+    monkeypatch.setattr(
+        learning_graph,
+        "_load_usage",
+        lambda: {
+            "iso-skill": {
+                "created_by": "agent",
+                "last_used_at": "2026-04-30T12:00:00+00:00",
+                "use_count": 1,
+            }
+        },
+    )
+
+    nodes = learning_graph.build_skill_nodes([("profile", tmp_path / "skills")])
+
+    assert nodes["iso-skill"].timestamp == 1_777_550_400
+
+
 def test_memory_is_cards_split_on_separator(tmp_path):
     home = tmp_path / ".hermes"
     (home / "memories").mkdir(parents=True)