diff --git a/pdme/model/model.py b/pdme/model/model.py
index c38e937..e3e4abb 100644
--- a/pdme/model/model.py
+++ b/pdme/model/model.py
@@ -47,6 +47,7 @@ class DipoleModel:
 		seed,
 		cost_function,
 		chain_length,
+		threshold_cost: float,
 		stdevs: pdme.subspace_simulation.MCMCStandardDeviation,
 		initial_cost: Optional[float] = None,
 		rng_arg: Optional[numpy.random.Generator] = None,
@@ -73,10 +74,9 @@ class DipoleModel:
 		chain: List[Tuple[float, numpy.ndarray]] = []
 		current = seed
 		if initial_cost is None:
-			cost_to_compare = cost_function(current)
+			current_cost = cost_function(current)
 		else:
-			cost_to_compare = initial_cost
-		current_cost = cost_to_compare
+			current_cost = initial_cost
 		for i in range(chain_length):
 			dips = []
 			for dipole_index, dipole in enumerate(current):
@@ -90,7 +90,7 @@ class DipoleModel:
 				dips
 			)
 			tentative_cost = cost_function(dips_array)
-			if tentative_cost < cost_to_compare:
+			if tentative_cost < threshold_cost:
 				chain.append((tentative_cost, dips_array))
 				current = dips_array
 				current_cost = tentative_cost
diff --git a/tests/model/test_log_spaced_fixed_orientation_fixedxy_orientation_mcmc.py b/tests/model/test_log_spaced_fixed_orientation_fixedxy_orientation_mcmc.py
index 12dab54..19b70d3 100644
--- a/tests/model/test_log_spaced_fixed_orientation_fixedxy_orientation_mcmc.py
+++ b/tests/model/test_log_spaced_fixed_orientation_fixedxy_orientation_mcmc.py
@@ -84,7 +84,7 @@ def test_log_spaced_fixedxy_orientation_mcmc_basic(snapshot):
 	stdevs = pdme.subspace_simulation.MCMCStandardDeviation([stdev])
 
 	chain = model.get_mcmc_chain(
-		seed, cost_function, 10, stdevs, rng_arg=numpy.random.default_rng(1515)
+		seed, cost_function, 10, cost_function(seed)[0], stdevs, rng_arg=numpy.random.default_rng(1515)
 	)
 
 	assert chain == snapshot
diff --git a/tests/model/test_log_spaced_fixed_orientation_free_orientation_mcmc.py b/tests/model/test_log_spaced_fixed_orientation_free_orientation_mcmc.py
index b5f7398..2b2e91b 100644
--- a/tests/model/test_log_spaced_fixed_orientation_free_orientation_mcmc.py
+++ b/tests/model/test_log_spaced_fixed_orientation_free_orientation_mcmc.py
@@ -84,7 +84,7 @@ def test_log_spaced_free_orientation_mcmc_basic(snapshot):
 	stdevs = pdme.subspace_simulation.MCMCStandardDeviation([stdev])
 
 	chain = model.get_mcmc_chain(
-		seed, cost_function, 10, stdevs, rng_arg=numpy.random.default_rng(1515)
+		seed, cost_function, 10, cost_function(seed)[0], stdevs, rng_arg=numpy.random.default_rng(1515)
 	)
 
 	assert chain == snapshot
diff --git a/tests/model/test_log_spaced_fixed_orientation_mcmc.py b/tests/model/test_log_spaced_fixed_orientation_mcmc.py
index 46a7f07..cd330a5 100644
--- a/tests/model/test_log_spaced_fixed_orientation_mcmc.py
+++ b/tests/model/test_log_spaced_fixed_orientation_mcmc.py
@@ -92,7 +92,7 @@ def test_log_spaced_fixed_orientation_mcmc_basic(snapshot):
 	stdevs = pdme.subspace_simulation.MCMCStandardDeviation([stdev])
 
 	chain = model.get_mcmc_chain(
-		seed, cost_function, 10, stdevs, rng_arg=numpy.random.default_rng(1515)
+		seed, cost_function, 10, cost_function(seed)[0], stdevs, rng_arg=numpy.random.default_rng(1515)
 	)
 
 	assert chain == snapshot