diff --git a/src/api/__init__.py b/src/api/__init__.py
index fff577c..4dd2e5b 100644
--- a/src/api/__init__.py
+++ b/src/api/__init__.py
@@ -1 +1,20 @@
-# decp.info — API privée. init_api(server) sera ajouté Task 6.
+from flask_smorest import Api
+
+from src.api import routes
+
+
+def init_api(server) -> None:
+    """Enregistre le blueprint d'API privée sur le serveur Flask."""
+    server.config.setdefault("API_TITLE", "decp.info API")
+    server.config.setdefault("API_VERSION", "v1")
+    server.config.setdefault("OPENAPI_VERSION", "3.0.3")
+    server.config.setdefault("OPENAPI_URL_PREFIX", "/api/v1")
+    server.config.setdefault("OPENAPI_JSON_PATH", "openapi.json")
+    server.config.setdefault("OPENAPI_SWAGGER_UI_PATH", "swagger")
+    server.config.setdefault(
+        "OPENAPI_SWAGGER_UI_URL",
+        "https://cdn.jsdelivr.net/npm/swagger-ui-dist/",
+    )
+
+    api = Api(server)
+    api.register_blueprint(routes.bp)
diff --git a/src/api/routes.py b/src/api/routes.py
new file mode 100644
index 0000000..759ff1b
--- /dev/null
+++ b/src/api/routes.py
@@ -0,0 +1,14 @@
+from flask_smorest import Blueprint
+
+bp = Blueprint(
+    "api_v1",
+    "api_v1",
+    url_prefix="/api/v1",
+    description="API privée decp.info — accès tabulaire aux marchés publics.",
+)
+
+
+@bp.route("/health")
+def health():
+    """Sonde de santé, sans authentification."""
+    return {"status": "ok"}
diff --git a/tests/api/test_health.py b/tests/api/test_health.py
new file mode 100644
index 0000000..3bddbfd
--- /dev/null
+++ b/tests/api/test_health.py
@@ -0,0 +1,16 @@
+from flask import Flask
+
+from src.api import init_api
+
+
+def _make_app():
+    app = Flask(__name__)
+    init_api(app)
+    return app
+
+
+def test_health_returns_ok_without_auth():
+    app = _make_app()
+    resp = app.test_client().get("/api/v1/health")
+    assert resp.status_code == 200
+    assert resp.get_json() == {"status": "ok"}