diff --git a/nextcloud_mcp_server/config.py b/nextcloud_mcp_server/config.py
index 993e1497..d4e60c9e 100644
--- a/nextcloud_mcp_server/config.py
+++ b/nextcloud_mcp_server/config.py
@@ -696,7 +696,9 @@ class Settings:
     fact_event_emitter: str = "none"  # none | nats | stdout
     ingest_bus_url: str | None = None  # required when ingest_mode=external
     embedding_gateway_url: str | None = None  # required when provider=gateway
-    embedding_gateway_model: str = "mistral-embed"  # logical model gateway routes
+    embedding_gateway_model: str = (
+        "mistral/mistral-embed"  # provider-namespaced id the gateway routes on
+    )
     # Gateway M2M OIDC client creds (separate realm; see _DEFAULTS comment).
     embedding_gateway_token_url: str | None = None
     embedding_gateway_client_id: str | None = None
diff --git a/nextcloud_mcp_server/embedding/gateway_client.py b/nextcloud_mcp_server/embedding/gateway_client.py
index 72aedc1a..82f37257 100644
--- a/nextcloud_mcp_server/embedding/gateway_client.py
+++ b/nextcloud_mcp_server/embedding/gateway_client.py
@@ -119,6 +119,16 @@ class GatewayProvider(OpenAIProvider):
         token_provider: GatewayTokenProvider | None = None,
         timeout: float = 120.0,
     ):
+        # The gateway exposes its OpenAI-compatible API under the /v1 base path
+        # (/v1/embeddings, /v1/models). Callers configure EMBEDDING_GATEWAY_URL
+        # as a bare origin (scheme://host:port) — the deployment's Service URL —
+        # so we append /v1 here. This base path is then used uniformly: the
+        # OpenAI SDK posts embeds to {base_url}/embeddings and _detect_dimension
+        # GETs {base_url}/models, both correctly landing under /v1. Idempotent —
+        # a URL already ending in /v1 (or /v1/) is left as-is.
+        normalized_base_url = base_url.rstrip("/")
+        if not normalized_base_url.endswith("/v1"):
+            normalized_base_url = f"{normalized_base_url}/v1"
         # AsyncOpenAI rejects an empty key; use a non-secret placeholder when
         # the gateway is unauthenticated. When a token provider is configured,
         # the real Bearer is set on the client before each request. The bare
@@ -126,7 +136,7 @@ class GatewayProvider(OpenAIProvider):
         # this is a public placeholder string, not a secret.
         super().__init__(
             api_key=_UNAUTHENTICATED_PLACEHOLDER,  # NOSONAR
-            base_url=base_url,
+            base_url=normalized_base_url,
             embedding_model=embedding_model,
             generation_model=None,  # gateway never generates
             timeout=timeout,
@@ -134,7 +144,7 @@ class GatewayProvider(OpenAIProvider):
         self._token_provider = token_provider
         logger.info(
             "Initialized gateway embedding provider: base_url=%s, model=%s, auth=%s",
-            base_url,
+            normalized_base_url,
             embedding_model,
             "oidc-m2m" if token_provider else "none",
         )
diff --git a/tests/unit/providers/test_gateway_provider.py b/tests/unit/providers/test_gateway_provider.py
index 923b33f3..1e941b8e 100644
--- a/tests/unit/providers/test_gateway_provider.py
+++ b/tests/unit/providers/test_gateway_provider.py
@@ -289,3 +289,59 @@ async def test_detect_dimension_skips_when_already_known(monkeypatch):
     await provider._detect_dimension()
     assert called["n"] == 0
     assert provider.get_dimension() == 1024
+
+
+# --- /v1 base-path normalization --------------------------------------------
+# EMBEDDING_GATEWAY_URL is configured as a bare origin (scheme://host:port);
+# the provider appends the gateway's /v1 base path so both the OpenAI SDK's
+# embed posts ({base}/embeddings) and discovery ({base}/models) land under /v1.
+
+
+def _client_base(provider: GatewayProvider) -> str:
+    return str(provider.client.base_url).rstrip("/")
+
+
+def test_bare_base_url_gets_v1_base_path():
+    provider = GatewayProvider(
+        base_url="http://gw:8083", embedding_model="mistral/mistral-embed"
+    )
+    assert _client_base(provider).endswith("/v1")
+
+
+def test_v1_base_url_is_idempotent():
+    # A URL that already carries /v1 (e.g. legacy config) is not doubled.
+    provider = GatewayProvider(
+        base_url="http://gw:8083/v1", embedding_model="mistral/mistral-embed"
+    )
+    base = _client_base(provider)
+    assert base.endswith("/v1")
+    assert not base.endswith("/v1/v1")
+
+
+def test_trailing_slash_base_url_normalized():
+    provider = GatewayProvider(
+        base_url="http://gw:8083/", embedding_model="mistral/mistral-embed"
+    )
+    base = _client_base(provider)
+    assert base.endswith("/v1")
+    assert not base.endswith("/v1/v1")
+
+
+async def test_detect_dimension_with_bare_base_url_hits_v1_models(monkeypatch):
+    """End-to-end of the fix: a bare-origin base_url still resolves the
+    dimension because discovery lands on /v1/models."""
+    seen = {}
+
+    def handler(request: httpx.Request) -> httpx.Response:
+        seen["url"] = str(request.url)
+        return httpx.Response(
+            200, json={"data": [{"id": "mistral/mistral-embed", "dimension": 1024}]}
+        )
+
+    _mock_async_client(monkeypatch, handler)
+    provider = GatewayProvider(
+        base_url="http://gw:8083", embedding_model="mistral/mistral-embed"
+    )
+    await provider._detect_dimension()
+    assert provider.get_dimension() == 1024
+    assert seen["url"].endswith("/v1/models")