Preserve raw source identity across coding workspaces

docs/engineering/external_conversation_import.md

@@ -148,6 +148,13 @@ report rather than hidden.
 
 ## Display in Conversations
 
+Raw-document identity includes provider account and workspace when present,
+matching the conversation's source scope. This prevents reused provider session
+IDs (including Gemini A2A runs with the same start time) from sharing one mutable
+raw-document pointer across workspaces. Existing raw artefacts remain retained;
+reconciliation can refresh an affected transcript's raw-document reference
+without replacing its history or dates.
+
 Imported conversations are hidden from the Conversations tray and its search
 results by default. Select **Show imported** in the tray filters to include them
 for the current page session. This uses the existing

src/backend/services/chat_history_service.py

@@ -4833,6 +4833,8 @@ def _event_fingerprint(entry: Mapping[str, Any]) -> str:
         == stored_manifest.get("parser_version")
         and existing_manifest.get("raw_file_copy_concept_id")
         == stored_manifest.get("raw_file_copy_concept_id")
+        and existing_manifest.get("raw_document_concept_id")
+        == stored_manifest.get("raw_document_concept_id")
     ):
         existing_synchronisation = existing_manifest.get("synchronisation")
         existing_divergence = (

src/backend/services/external_conversation_import_service.py

@@ -1548,6 +1548,18 @@ def _build_source_record(
         f"external-import://custodian/{custodian_scope}/"
         f"{package.provider}/{package.source_session_id}"
     )
+    # Provider session IDs can repeat across accounts/workspaces. Raw custody
+    # must distinguish the same source scopes as the conversation projection.
+    # Hash exact values before the ingestion layer normalises paths to lowercase.
+    if package.source_account or package.source_workspace:
+        source_scope = hashlib.sha256(
+            json.dumps(
+                [package.source_account or "", package.source_workspace or ""],
+                ensure_ascii=True,
+                separators=(",", ":"),
+            ).encode("utf-8")
+        ).hexdigest()
+        canonical_source_path += f"/scope/{source_scope}"
     return SessionRecord(
         environment=package.provider,
         source_session_id=package.source_session_id,

tests/backend/test_external_conversation_import_service.py

@@ -112,6 +112,36 @@ def parse(start: str, *, append: bool = False, session_id: str = "a2a-server"):
     )
 
 
+def test_raw_custody_distinguishes_gemini_workspace_and_account(tmp_path):
+    def record(workspace, account=None, *, append=False):
+        messages = [{"type": "user", "content": "Inspect this workspace"}]
+        if append:
+            messages.append({"type": "gemini", "content": "Inspected"})
+        path = tmp_path / "same-filename.jsonl"
+        path.write_bytes(_jsonl({
+            "sessionId": "a2a-server",
+            "startTime": "2026-06-28T16:27:59Z",
+            "projectHash": workspace,
+            "messages": messages,
+        }))
+        package = external_conversation_import_service.parse_external_conversation_file(
+            path, provider_hint="gemini", source_account=account
+        )
+        return external_conversation_import_service._build_source_record(
+            path=path, package=package, custodian_user_id="#V#user", namespace="#V#user"
+        )
+
+    first = record("workspace")
+    grown = record("workspace", append=True)
+    other_workspace = record("Workspace")
+    other_account = record("workspace", "another-account")
+    assert first.source_session_id == other_workspace.source_session_id
+    assert first.document_concept_id == grown.document_concept_id
+    assert len({first.document_concept_id, other_workspace.document_concept_id,
+                other_account.document_concept_id}) == 3
+    assert "another-account" not in other_account.canonical_source_path
+
+
 def test_codex_parser_projects_visible_messages_without_importing_instructions():
     package = parse_external_conversation_bytes(
         _jsonl(
@@ -389,6 +419,18 @@ def test_chat_projection_is_read_only_idempotent_and_actor_scoped(monkeypatch):
         manifest=manifest,
     )
     assert repeated["action"] == "unchanged"
+    # A corrected raw-document reference must refresh even when bytes, parsed
+    # events and the file-copy reference did not change. Keep transcript intact.
+    history_before = collection.find_one({"session_id": "external-session"})["history"]
+    repaired = chat_history_service.upsert_external_conversation_projection(
+        user_id="#V#user", session_id="external-session", session_name="Imported session",
+        namespace="#V#user@org", organisation_concept_id="#V#org", role_in_org="member",
+        history=history, manifest={**manifest, "raw_document_concept_id": "#V#scoped-source"},
+    )
+    assert repaired["action"] == "refreshed"
+    after = collection.find_one({"session_id": "external-session"})
+    assert after["external_conversation_import"]["raw_document_concept_id"] == "#V#scoped-source"
+    assert after["history"] == history_before
     assert (
         collection.find_one({"session_id": "external-session"})["session_name"]
         == "Imported session"