diff --git a/headroom/cli/doctor.py b/headroom/cli/doctor.py
index f1f06b380..ae8e4cc55 100644
--- a/headroom/cli/doctor.py
+++ b/headroom/cli/doctor.py
@@ -48,6 +48,13 @@ SKIP = "skip"
 _LOOPBACK_URL_RE = re.compile(r"https?://(?:127\.0\.0\.1|localhost):(\d+)")
 _CODEX_BASE_URL_RE = re.compile(r'base_url\s*=\s*"https?://(?:127\.0\.0\.1|localhost):(\d+)')
 
+# Ollama's fixed default port. `ollama launch claude` writes
+# ``ANTHROPIC_BASE_URL=http://127.0.0.1:11434`` into the launched Claude Code
+# child, which outranks the persistent-install env block and silently bypasses
+# the Headroom proxy (issue #2199). Recognized so the routing diagnostic names
+# the collision instead of telling the user to re-probe port 11434.
+_OLLAMA_DEFAULT_PORT = 11434
+
 
 @dataclass
 class CheckResult:
@@ -344,6 +351,22 @@ def _classify_routing_url(name: str, url: str, port: int, *, source: str) -> Che
         )
     found_port = int(match.group(1))
     if found_port != port:
+        if found_port == _OLLAMA_DEFAULT_PORT:
+            # Not a mis-probed Headroom port — this is Ollama's endpoint, so
+            # `headroom doctor --port 11434` would only chase a red herring.
+            return CheckResult(
+                name=name,
+                status=WARN,
+                summary=(
+                    f"points at Ollama ({url}), not the Headroom proxy ({source}) — "
+                    "`ollama launch claude` bypasses the persistent Headroom route"
+                ),
+                hint=(
+                    "both claim ANTHROPIC_BASE_URL; run Ollama-backed sessions "
+                    "through Headroom by chaining the proxy at its Ollama upstream "
+                    "(see issue #2199)"
+                ),
+            )
         return CheckResult(
             name=name,
             status=WARN,
diff --git a/tests/test_cli_doctor.py b/tests/test_cli_doctor.py
index 6bce283e8..c93a6d9a4 100644
--- a/tests/test_cli_doctor.py
+++ b/tests/test_cli_doctor.py
@@ -390,6 +390,17 @@ class TestShellEnv:
         env = {"ANTHROPIC_BASE_URL": "https://api.anthropic.com"}
         assert check_shell_env(env, 8787).status == WARN
 
+    def test_ollama_launch_url_names_the_collision(self):
+        # `ollama launch claude` points Claude Code at Ollama's :11434, which
+        # outranks the persistent Headroom route (issue #2199). The diagnostic
+        # must name Ollama, not tell the user to re-probe port 11434.
+        env = {"ANTHROPIC_BASE_URL": "http://127.0.0.1:11434"}
+        result = check_shell_env(env, 8787)
+        assert result.status == WARN
+        assert "Ollama" in result.summary
+        assert "#2199" in (result.hint or "")
+        assert "--port 11434" not in (result.hint or "")
+
 
 class TestSavings:
     def test_from_stats_passes_with_totals(self, tmp_path):