diff --git a/broker/JFJochBrokerParser.cpp b/broker/JFJochBrokerParser.cpp
index 1a322e56..2ee30f88 100644
--- a/broker/JFJochBrokerParser.cpp
+++ b/broker/JFJochBrokerParser.cpp
@@ -179,6 +179,13 @@ void ParseFacilityConfiguration(const org::openapitools::server::model::Jfjoch_s
 
     if (j.braggIntegrationIsSet())
         experiment.ImportBraggIntegrationSettings(Convert(j.getBraggIntegration()));
+    else
+        // A config with no bragg_integration block still has to bootstrap a concrete max_hkl, or the
+        // predictor falls back to deriving the hkl cube from the refined cell and a live acquisition's
+        // per-image cost is decided by whichever crystal is mounted. None of the shipped configs sets
+        // the block, so this is the normal path online.
+        experiment.ImportBraggIntegrationSettings(
+                BraggIntegrationSettings().MaxHKL(BRAGG_ONLINE_DEFAULT_MAX_HKL));
 
     if (j.darkMaskIsSet())
         experiment.ImportDarkMaskSettings(Convert(j.getDarkMask()));
diff --git a/common/BraggIntegrationSettings.h b/common/BraggIntegrationSettings.h
index 2e3e5b23..4f917155 100644
--- a/common/BraggIntegrationSettings.h
+++ b/common/BraggIntegrationSettings.h
@@ -12,6 +12,10 @@
 // spots - see docs/CPU_DATA_ANALYSIS.md (Bragg integration).
 enum class IntegratorMode { BoxSum, ProfileGaussian, ProfileEmpirical };
 
+// The hkl half-width the broker bootstraps when a config carries no bragg_integration block. Matches
+// the max_hkl default in broker/jfjoch_api.yaml, so an omitting client and an omitting config agree.
+constexpr int BRAGG_ONLINE_DEFAULT_MAX_HKL = 100;
+
 class BraggIntegrationSettings {
     IntegratorMode integrator_mode = IntegratorMode::ProfileGaussian;
     float r_1 = 4;
@@ -39,6 +43,8 @@ class BraggIntegrationSettings {
     //
     // Unset (the default) means "take it from the refined cell", which is exact: the predictor keeps
     // only |q| <= 1/d_min and h = a.q, so no reflection can have |h| > a/d_min. See MaxHKLForCell.
+    // Offline that is what is wanted. ONLINE it is not: the broker bootstraps a concrete value
+    // (BRAGG_ONLINE_DEFAULT_MAX_HKL) so per-image cost stays predictable across samples.
     std::optional<int> max_hkl;
 
 public: