diff --git a/Makefile b/Makefile
index b453c6238..f3ee165ce 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ export TMPDIR := /var/tmp
 PYTEST_BASETEMP_INIT := BASETEMP=$$(mktemp -d /var/tmp/solstone-pytest-XXXXXX); trap 'rm -rf "$$BASETEMP"' EXIT INT TERM;
 PYTEST_BASETEMP_FLAG := --basetemp "$$BASETEMP"
 
-.PHONY: install hopper-install uninstall test test-cov test-integration test-performance test-app test-only format format-check install-checks ci clean clean-install coverage watch versions update update-prices preflight pre-commit skills render-packaging check-rust-fmt check-rust-msrv check-rust-clippy check-rust-test check-rust-ios check-rust-deny audit openapi check-openapi contract check-contract journal-resolution-vectors check-journal-resolution-vectors dev all sandbox sandbox-stop install-models parakeet-helper parakeet-helper-clean wheel-macos wheel-macos-clean verify verify-api verify-schemathesis update-api-baselines eval-schemas service-logs check-layer-hygiene check-api-conventions check-journal-io-access check-journal-io-mechanic check-journal-config-owner check-call-http-only check-no-legacy-chat check-tools-http-only check-access-imports-clean check-convey-bind-imports-clean check-schema-bounds check-thin-base-install check-cogitate-prompts smoke-cogitate release release-test FORCE
+.PHONY: install hopper-install uninstall test test-cov test-integration test-performance test-app test-only format format-check install-checks ci clean clean-install coverage watch versions update update-prices preflight pre-commit skills render-packaging check-rust-fmt check-rust-msrv check-rust-clippy check-rust-test check-rust-ios check-rust-deny audit openapi check-openapi check-openapi-observer-client-contract contract check-contract journal-resolution-vectors check-journal-resolution-vectors dev all sandbox sandbox-stop install-models parakeet-helper parakeet-helper-clean wheel-macos wheel-macos-clean verify verify-api verify-schemathesis update-api-baselines eval-schemas service-logs check-layer-hygiene check-api-conventions check-journal-io-access check-journal-io-mechanic check-journal-config-owner check-call-http-only check-no-legacy-chat check-tools-http-only check-access-imports-clean check-convey-bind-imports-clean check-schema-bounds check-thin-base-install check-cogitate-prompts smoke-cogitate release release-test FORCE
 
 # Default target - install package in editable mode
 all: install
@@ -684,6 +684,10 @@ openapi:
 check-openapi: .installed
 	$(VENV_BIN)/python scripts/check_openapi_contract.py
 	$(VENV_BIN)/python scripts/build_openapi_contract.py --check
+	$(MAKE) check-openapi-observer-client-contract
+
+check-openapi-observer-client-contract: .installed
+	$(VENV_BIN)/python scripts/check_observer_client_contract_bundle.py
 
 journal-resolution-vectors:
 	$(VENV_BIN)/python scripts/build_journal_resolution_vectors.py
diff --git a/scripts/check_observer_client_contract_bundle.py b/scripts/check_observer_client_contract_bundle.py
new file mode 100644
index 000000000..70a85197c
--- /dev/null
+++ b/scripts/check_observer_client_contract_bundle.py
@@ -0,0 +1,90 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: AGPL-3.0-only
+# Copyright (c) 2026 sol pbc
+
+"""Check the generated observer-client OpenAPI contract bundle."""
+
+from __future__ import annotations
+
+import sys
+from collections.abc import Callable
+from pathlib import Path
+
+from solstone.convey.contract.observer_bundle import (
+    BUNDLE_REL_DIR,
+    stale_bundle_paths,
+)
+from solstone.convey.contract.observer_bundle_compatibility import (
+    check_bundle_compatibility,
+)
+from solstone.convey.contract.observer_bundle_verification import (
+    check_consumer_audit_coverage,
+    verify_committed_bundle,
+)
+
+ROOT = Path(__file__).resolve().parent.parent
+
+
+def _staleness_failures() -> list[str]:
+    stale = stale_bundle_paths(ROOT)
+    if not stale:
+        return []
+    paths = ", ".join(str(path) for path in stale)
+    return [
+        "observer client contract bundle staleness failed: "
+        f"{paths}. Recovery: run make openapi."
+    ]
+
+
+def _manifest_failures() -> list[str]:
+    verify_committed_bundle(ROOT)
+    return []
+
+
+def _compatibility_failures() -> list[str]:
+    return check_bundle_compatibility(ROOT)
+
+
+def _coverage_failures() -> list[str]:
+    return check_consumer_audit_coverage(ROOT)
+
+
+def _run_gate(name: str, fn: Callable[[], list[str]]) -> bool:
+    try:
+        failures = fn()
+    except Exception as exc:
+        failures = [
+            f"observer client contract {name} failed: {exc}. "
+            "Recovery: run make openapi, repair the bundle, or apply the "
+            "required SemVer bump."
+        ]
+    if not failures:
+        print(f"observer-client-contract {name}: pass")
+        return False
+    for failure in failures:
+        print(failure, file=sys.stderr)
+    return True
+
+
+def main() -> int:
+    failed = False
+    gates: tuple[tuple[str, Callable[[], list[str]]], ...] = (
+        ("staleness", _staleness_failures),
+        ("manifest", _manifest_failures),
+        ("compatibility", _compatibility_failures),
+        ("windows-linux-coverage", _coverage_failures),
+    )
+    for name, fn in gates:
+        failed = _run_gate(name, fn) or failed
+    if failed:
+        print(
+            f"observer-client-contract: failed for {BUNDLE_REL_DIR}.",
+            file=sys.stderr,
+        )
+        return 1
+    print(f"observer-client-contract: pass for {BUNDLE_REL_DIR}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())
diff --git a/scripts/export_observer_client_contract_bundle.py b/scripts/export_observer_client_contract_bundle.py
new file mode 100644
index 000000000..faf832bb5
--- /dev/null
+++ b/scripts/export_observer_client_contract_bundle.py
@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: AGPL-3.0-only
+# Copyright (c) 2026 sol pbc
+
+"""Export the committed observer-client OpenAPI contract bundle."""
+
+from __future__ import annotations
+
+import argparse
+import sys
+from pathlib import Path
+
+from solstone.convey.contract.observer_bundle_export import (
+    BundleExportRefused,
+    export_bundle,
+)
+
+ROOT = Path(__file__).resolve().parent.parent
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("destination", type=Path, help="New destination directory.")
+    args = parser.parse_args()
+
+    try:
+        destination = export_bundle(args.destination, ROOT)
+    except BundleExportRefused as exc:
+        print(str(exc), file=sys.stderr)
+        return 1
+    print(f"exported observer client contract bundle to {destination}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())