diff --git a/.gitattributes b/.gitattributes
index f8975c9..dd5054a 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -5,3 +5,8 @@
 # checksums and making every refresh from upstream show a whole-file diff.
 src/oold/validation/meta/*/**  -text
 tests/data/oold/**             -text
+
+# tests/data/resolver_cache/ holds a Resolver disk-cache entry, named by the sha256 of a fixed
+# URL. It carries no upstream checksum, but the same autocrlf rewrite would still turn it into
+# a CRLF file, which is not what the "written with LF" test fixture convention expects.
+tests/data/resolver_cache/**   -text
diff --git a/tests/data/resolver_cache/66a1009a2cf528dd525ec0c0150488fe.json b/tests/data/resolver_cache/66a1009a2cf528dd525ec0c0150488fe.json
new file mode 100644
index 0000000..a17f01d
--- /dev/null
+++ b/tests/data/resolver_cache/66a1009a2cf528dd525ec0c0150488fe.json
@@ -0,0 +1,5 @@
+{
+  "$id": "https://example.org/oold-warm-cache-fixture.schema.json",
+  "title": "Warm",
+  "type": "object"
+}
diff --git a/tests/test_validation/conftest.py b/tests/test_validation/conftest.py
index 1bb4ec7..c8fe257 100644
--- a/tests/test_validation/conftest.py
+++ b/tests/test_validation/conftest.py
@@ -13,6 +13,7 @@
 COMPLIANCE = DATA / "compliance"
 REMOTE_CONTEXT = DATA / "remote_context"
 X_OOLD_CONTEXT = DATA / "x_oold_context"
+RESOLVER_CACHE = DATA.parent / "resolver_cache"
 
 
 @pytest.fixture
@@ -43,6 +44,16 @@ def x_oold_context_dir() -> Path:
     return X_OOLD_CONTEXT
 
 
+@pytest.fixture
+def resolver_cache_dir() -> Path:
+    """A committed `Resolver` disk-cache entry, named by the sha256 digest of a fixed URL.
+
+    Proves a warmed cache satisfies an offline fetch without a network mock standing in for the
+    retrieval layer itself.
+    """
+    return RESOLVER_CACHE
+
+
 @pytest.fixture
 def isolated_cache(tmp_path, monkeypatch) -> Path:
     """Point the document and meta caches at a temporary directory.
diff --git a/tests/test_validation/test_pipeline.py b/tests/test_validation/test_pipeline.py
index 91dd81d..037c25f 100644
--- a/tests/test_validation/test_pipeline.py
+++ b/tests/test_validation/test_pipeline.py
@@ -2,6 +2,11 @@
 
 from __future__ import annotations
 
+import functools
+import http.server
+import json
+import threading
+
 import pytest
 
 from oold.validation import Options, run_compliance, validate_directory, validate_instance, validate_schema
@@ -67,6 +72,85 @@ def test_a_context_chain_leaving_the_directory_resolves(remote_context_dir):
     assert "context.remote" in _ids(report, OK)
 
 
+def test_a_genuinely_remote_context_is_fetched_over_http(tmp_path):
+    """`remote_context_dir` above only ever leaves the *directory*; nothing in the corpus makes
+    an `@context` chain leave the filesystem, so `Resolver` never actually opens a socket. That
+    matters because socket retrieval is exactly the layer #119 proposes moving onto
+    `referencing`, and no fixture touching it means a regression there would pass CI.
+
+    A loopback HTTP server, bound to an OS-assigned port and shut down in a `finally`, is the
+    genuinely remote sibling: the schema and its remote context are templated into `tmp_path`
+    (a committed fixture cannot carry a port that varies per run), and the handler records every
+    request it serves, so the assertion below is that the context was actually fetched over the
+    wire, not resolved from disk by accident.
+    """
+    served = tmp_path / "served"
+    served.mkdir()
+    requested: list[str] = []
+
+    class RecordingHandler(http.server.SimpleHTTPRequestHandler):
+        def do_GET(self) -> None:
+            requested.append(self.path)
+            super().do_GET()
+
+        def log_message(self, format: str, *args: object) -> None:
+            pass  # keep the test's own output free of per-request access logging
+
+    handler = functools.partial(RecordingHandler, directory=str(served))
+    server = http.server.ThreadingHTTPServer(("127.0.0.1", 0), handler)
+    thread = threading.Thread(target=server.serve_forever, daemon=True)
+    thread.start()
+
+    try:
+        base_url = f"http://127.0.0.1:{server.server_port}/"
+        (served / "Thing.schema.json").write_text(
+            json.dumps({
+                "$schema": "https://oo-ld.org/latest/meta/oold-meta-schema.json",
+                "$id": "Thing.schema.json",
+                "x-oold-instance-rdf-type": ["schema:Thing"],
+                "@context": {"schema": "http://schema.org/", "name": "schema:name"},
+                "title": "Thing",
+                "type": "object",
+                "properties": {"name": {"type": "string"}},
+            }),
+            encoding="utf-8",
+        )
+
+        case_dir = tmp_path / "case"
+        case_dir.mkdir()
+        (case_dir / "RemoteLeaf.schema.json").write_text(
+            json.dumps({
+                "$schema": "https://oo-ld.org/latest/meta/oold-meta-schema.json",
+                "$id": "RemoteLeaf.schema.json",
+                "title": "RemoteLeaf",
+                "x-oold-instance-rdf-type": ["schema:Thing"],
+                "@context": [
+                    f"{base_url}Thing.schema.json",
+                    {"schema": "http://schema.org/", "nickname": "schema:alternateName"},
+                ],
+                "type": "object",
+                "required": ["name"],
+                "properties": {"name": {"type": "string"}, "nickname": {"type": "string"}},
+            }),
+            encoding="utf-8",
+        )
+
+        report = validate_schema(
+            case_dir / "RemoteLeaf.schema.json",
+            Options(meta=("latest",), offline=False, cache_dir=tmp_path / "cache"),
+        )
+    finally:
+        server.shutdown()
+        server.server_close()
+        thread.join()
+
+    assert report.passed, [f"{c.id}: {c.message}" for c in report.failures()]
+    assert "context.remote" in _ids(report, OK)
+    assert any(path.endswith("Thing.schema.json") for path in requested), (
+        f"the context was never actually requested over the socket: {requested!r}"
+    )
+
+
 def test_a_property_mapped_only_through_x_oold_context_is_not_reported(x_oold_context_dir):
     """x-oold-context (OOLD-EXT-4966) is a legitimate way to map a term; one mapped only there
     must not be reported as unmapped just because plain JSON-LD cannot see that mapping."""
diff --git a/tests/test_validation/test_resolve.py b/tests/test_validation/test_resolve.py
index bdf04ce..4b4c480 100644
--- a/tests/test_validation/test_resolve.py
+++ b/tests/test_validation/test_resolve.py
@@ -241,6 +241,22 @@ def test_properties_nesting_is_depth_neutral():
     assert bound_schema(nested, max_depth=2) == nested
 
 
+def test_a_warm_cache_entry_resolves_offline_and_a_missing_one_is_refused(resolver_cache_dir):
+    """`tests/data/resolver_cache/` commits one entry ahead of time, named by the sha256 digest
+    `Resolver._cache_file` itself derives from the URL. That is what lets this prove the offline
+    guarantee the vendored meta-schemas depend on - a previously warmed cache satisfies a fetch -
+    without a network mock standing in for the retrieval layer #119 is about to move onto
+    `referencing`.
+    """
+    resolver = Resolver(cache_dir=resolver_cache_dir, offline=True)
+
+    document = resolver.fetch("https://example.org/oold-warm-cache-fixture.schema.json")
+    assert document["title"] == "Warm"
+
+    with pytest.raises(SchemaResolutionError, match="offline"):
+        resolver.fetch("https://example.org/oold-warm-cache-fixture-missing.schema.json")
+
+
 def test_disk_cache_is_reused(tmp_path, monkeypatch):
     cache = tmp_path / "cache"
     calls = []