diff --git a/Makefile b/Makefile
index a46f399..b820c3a 100644
--- a/Makefile
+++ b/Makefile
@@ -19,16 +19,15 @@ export SHELLOPTS:=$(if $(SHELLOPTS),$(SHELLOPTS):)pipefail:errexit
 
 ## Compile core docker image
 build-core-image: 
-	cd core
 	docker build \
+	-f core/Dockerfile \
 	--build-arg SECRET_KEY_BASE=local-make-secret \
 	--build-arg MIX_ENV="prod" \
 	-t core .
 
 ## Compile worker docker image
 build-worker-image: 
-	cd worker
-	docker build --build-arg MIX_ENV="prod" -t worker .
+	docker build -f worker/Dockerfile --build-arg MIX_ENV="prod" -t worker .
 
 ## Run credo --strict
 credo-core: 
diff --git a/core/lib/core/adapters/commands/test.ex b/core/lib/core/adapters/commands/test.ex
index f939e80..a594553 100644
--- a/core/lib/core/adapters/commands/test.ex
+++ b/core/lib/core/adapters/commands/test.ex
@@ -19,7 +19,7 @@ defmodule Core.Adapters.Commands.Test do
   alias Data.InvokeResult
 
   @impl true
-  def send_invoke(_worker, name, _ns, _hash, _args) do
+  def send_invoke(_worker, name, _ns, _hash, _args, _metadata \\ {}) do
     {:ok, %InvokeResult{result: name}}
   end
 
diff --git a/core/lib/core/adapters/commands/worker.ex b/core/lib/core/adapters/commands/worker.ex
index 5c09b17..f896590 100644
--- a/core/lib/core/adapters/commands/worker.ex
+++ b/core/lib/core/adapters/commands/worker.ex
@@ -32,9 +32,9 @@ defmodule Core.Adapters.Commands.Worker do
   #                                  Only the send_invoke call should return this.
 
   @impl true
-  def send_invoke(worker, name, mod, hash, args) do
+  def send_invoke(worker, name, mod, hash, args, metadata \\ {}) do
     worker_addr = {:worker, worker}
-    cmd = {:invoke, %{name: name, module: mod, hash: hash}, args}
+    cmd = {:invoke, %{name: name, module: mod, hash: hash, metadata: metadata}, args}
     Logger.info("Sending invoke for #{mod}/#{name} to #{inspect(worker_addr)}")
 
     case GenServer.call(worker_addr, cmd, 60_000) do
diff --git a/core/lib/core/adapters/telemetry/collector.ex b/core/lib/core/adapters/telemetry/collector.ex
index af20dd2..0dca879 100644
--- a/core/lib/core/adapters/telemetry/collector.ex
+++ b/core/lib/core/adapters/telemetry/collector.ex
@@ -129,7 +129,8 @@ defmodule Core.Adapters.Telemetry.Collector do
     Enum.reduce(result_list, %{}, fn result, acc ->
       case result do
         %{"metric" => %{"__name__" => name}, "value" => [_, value]} ->
-          Map.put(acc, name, value)
+          {float_val, _} = Float.parse(value)
+          Map.put(acc, name, float_val)
 
         _ ->
           acc
diff --git a/core/lib/core/domain/invoker.ex b/core/lib/core/domain/invoker.ex
index b501ca0..0e001f7 100644
--- a/core/lib/core/domain/invoker.ex
+++ b/core/lib/core/domain/invoker.ex
@@ -19,7 +19,6 @@ defmodule Core.Domain.Invoker do
   require Logger
 
   alias Core.FunctionsMetadata
-  alias Data.FunctionMetadata
 
   alias Core.Domain.{
     Functions,
@@ -30,6 +29,7 @@ defmodule Core.Domain.Invoker do
     Scheduler
   }
 
+  alias Data.FunctionMetadata
   alias Data.FunctionStruct
   alias Data.InvokeParams
   alias Data.InvokeResult
@@ -68,11 +68,11 @@ defmodule Core.Domain.Invoker do
           metadata: struct(FunctionMetadata, %{tag: metadata.tag, capacity: metadata.capacity})
         })
 
-      with {:ok, worker} <- Nodes.worker_nodes() |> Scheduler.select(func, ivk.config) do
+      with {:ok, worker} <- Nodes.worker_nodes() |> Scheduler.select(func, ivk.config, ivk.args) do
         update_concurrent(worker, +1)
 
         out =
-          case invoke_without_code(worker, ivk, f.hash) do
+          case invoke_without_code(worker, ivk, f.hash, func.metadata) do
             {:error, :code_not_found, handler} ->
               [%{code: code}] = Functions.get_code_by_name_in_mod!(ivk.function, ivk.module)
 
@@ -121,12 +121,12 @@ defmodule Core.Domain.Invoker do
     end
   end
 
-  @spec invoke_without_code(atom(), InvokeParams.t(), binary()) ::
+  @spec invoke_without_code(atom(), InvokeParams.t(), binary(), FunctionMetadata.t()) ::
           {:ok, InvokeResult.t()} | {:error, :code_not_found, pid()} | invoke_errors()
-  def invoke_without_code(worker, ivk, hash) do
+  def invoke_without_code(worker, ivk, hash, metadata \\ %FunctionMetadata{}) do
     Logger.debug("Invoker: invoking #{ivk.module}/#{ivk.function} without code")
     # send invocation without code
-    Commands.send_invoke(worker, ivk.function, ivk.module, hash, ivk.args)
+    Commands.send_invoke(worker, ivk.function, ivk.module, hash, ivk.args, metadata)
   end
 
   @spec invoke_with_code(atom(), pid(), InvokeParams.t(), FunctionStruct.t()) ::
diff --git a/core/lib/core/domain/policies/app.ex b/core/lib/core/domain/policies/app.ex
index e2e5dae..7c7ab05 100644
--- a/core/lib/core/domain/policies/app.ex
+++ b/core/lib/core/domain/policies/app.ex
@@ -34,6 +34,7 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.APP do
   - configuration: an APP script (Data.Configurations.APP), generally obtained through parsing using the Core.Domain.Policies.Parsers.APP module.
   - workers: a list of Data.Worker structs, each with relevant worker metrics.
   - function: a Data.FunctionStruct struct, with the necessary function information. It must contain function metadata, specifically a tag and a capacity.
+  - args: not used
 
   ## Returns
   - {:ok, wrk} if a suitable worker was found, with `wrk` being the worker.
@@ -43,12 +44,15 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.APP do
   - {:error, :no_function_metadata} if the given FunctionStruct does not include the necessary metadata (i.e. tag, capacity).
   - {:error, :invalid_input} if the given input was invalid in any other way (e.g. wrong types).
   """
-  @spec select(APP.t(), [Data.Worker.t()], Data.FunctionStruct.t()) ::
+  @spec select(APP.t(), [Data.Worker.t()], Data.FunctionStruct.t(), map()) ::
           {:ok, Data.Worker.t()} | select_errors()
+  def select(config, workers, function, args \\ %{})
+
   def select(
         %APP{tags: tags} = _configuration,
         [_ | _] = workers,
-        %Data.FunctionStruct{metadata: %{tag: tag_name, capacity: _function_capacity}} = function
+        %Data.FunctionStruct{metadata: %{tag: tag_name, capacity: _function_capacity}} = function,
+        _
       ) do
     default = tags |> Map.get("default")
     tag = tags |> Map.get(tag_name, default)
@@ -75,15 +79,15 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.APP do
     end
   end
 
-  def select(%APP{tags: _}, [], _) do
+  def select(%APP{tags: _}, [], _, _) do
     {:error, :no_workers}
   end
 
-  def select(%APP{tags: _}, _, %Data.FunctionStruct{metadata: nil}) do
+  def select(%APP{tags: _}, _, %Data.FunctionStruct{metadata: nil}, _) do
     {:error, :no_function_metadata}
   end
 
-  def select(_, _, _) do
+  def select(_, _, _, _) do
     {:error, :invalid_input}
   end
 
@@ -158,7 +162,8 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.APP do
             Core.Domain.Policies.SchedulingPolicy.select(
               %Data.Configurations.Empty{},
               wrk,
-              function
+              function,
+              %{}
             )
         end
     end
diff --git a/core/lib/core/domain/policies/default.ex b/core/lib/core/domain/policies/default.ex
index 7ccc897..5719dfb 100644
--- a/core/lib/core/domain/policies/default.ex
+++ b/core/lib/core/domain/policies/default.ex
@@ -20,10 +20,13 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.Empty do
   # since otherwise in situations where e.g. Prometheus is down, we would always have no workers
   @spec select(Empty.t(), [Data.Worker.t()], Data.FunctionStruct.t()) ::
           {:ok, Data.Worker.t()} | {:error, :no_workers} | {:error, :no_valid_workers}
+  def select(config, workers, function, args \\ %{})
+
   def select(
         %Empty{},
         [_ | _] = workers,
-        %Data.FunctionStruct{metadata: %Data.FunctionMetadata{capacity: c}}
+        %Data.FunctionStruct{metadata: %Data.FunctionMetadata{capacity: c}},
+        _
       ) do
     selected_worker =
       workers
@@ -45,11 +48,11 @@ defimpl Core.Domain.Policies.SchedulingPolicy, for: Data.Configurations.Empty do
     end
   end
 
-  def select(%Empty{}, _, %Data.FunctionStruct{metadata: nil}) do
+  def select(%Empty{}, _, %Data.FunctionStruct{metadata: nil}, _) do
     {:error, :no_function_metadata}
   end
 
-  def select(%Empty{}, [], _) do
+  def select(%Empty{}, [], _, _) do
     {:error, :no_workers}
   end
 end
diff --git a/core/lib/core/domain/policies/scheduling_policy.ex b/core/lib/core/domain/policies/scheduling_policy.ex
index 175dd6b..c623342 100644
--- a/core/lib/core/domain/policies/scheduling_policy.ex
+++ b/core/lib/core/domain/policies/scheduling_policy.ex
@@ -21,7 +21,7 @@ defprotocol Core.Domain.Policies.SchedulingPolicy do
   @doc """
     Should select a worker from a list of workers, given a specific configuration.
   """
-  @spec select(t, [Data.Worker.t()], Data.FunctionStruct.t()) ::
+  @spec select(t, [Data.Worker.t()], Data.FunctionStruct.t(), map()) ::
           {:ok, Data.Worker.t()} | {:error, any}
-  def select(configuration, workers, function)
+  def select(configuration, workers, function, args)
 end
diff --git a/core/lib/core/domain/ports/commands.ex b/core/lib/core/domain/ports/commands.ex
index 718bdec..2e5a524 100644
--- a/core/lib/core/domain/ports/commands.ex
+++ b/core/lib/core/domain/ports/commands.ex
@@ -17,12 +17,13 @@ defmodule Core.Domain.Ports.Commands do
   Port for sending commands to workers.
   """
 
+  alias Data.FunctionMetadata
   alias Data.FunctionStruct
   alias Data.InvokeResult
 
   @adapter :core |> Application.compile_env!(__MODULE__) |> Keyword.fetch!(:adapter)
 
-  @callback send_invoke(atom(), String.t(), String.t(), binary(), map()) ::
+  @callback send_invoke(atom(), String.t(), String.t(), binary(), map(), FunctionMetadata.t()) ::
               {:ok, InvokeResult.t()} | {:error, :code_not_found, pid()} | {:error, any()}
   @callback send_invoke_with_code(atom(), pid(), FunctionStruct.t()) ::
               {:ok, InvokeResult.t()} | {:error, any()}
@@ -36,9 +37,9 @@ defmodule Core.Domain.Ports.Commands do
   Sends an invoke command to a worker passing the function name, module, hash and args.
   It requires a worker (a fully qualified name of another node with the :worker actor on) and function arguments can be empty.
   """
-  @spec send_invoke(atom(), String.t(), String.t(), binary(), map()) ::
+  @spec send_invoke(atom(), String.t(), String.t(), binary(), map(), FunctionMetadata.t()) ::
           {:ok, InvokeResult.t()} | {:error, :code_not_found, pid()} | {:error, any()}
-  defdelegate send_invoke(worker, f_name, ns, hash, args), to: @adapter
+  defdelegate send_invoke(worker, f_name, ns, hash, args, metadata), to: @adapter
 
   @doc """
   Sends an invoke command to a worker passing a struct with the function name, module and the code (wasm file binary).
diff --git a/core/lib/core/domain/scheduler.ex b/core/lib/core/domain/scheduler.ex
index 483a7cf..650c79d 100644
--- a/core/lib/core/domain/scheduler.ex
+++ b/core/lib/core/domain/scheduler.ex
@@ -29,14 +29,16 @@ defmodule Core.Domain.Scheduler do
   """
   @spec select([worker_atom()], Data.FunctionStruct.t(), configuration()) ::
           {:ok, worker_atom()} | {:error, :no_workers} | {:error, :no_valid_workers}
-  def select([], _, _) do
+  def select(workers, function, config, args \\ %{})
+
+  def select([], _, _, _args) do
     Logger.warn("Scheduler: tried selection with NO workers")
     {:error, :no_workers}
   end
 
   # NOTE: if we move this to a NIF, we should only pass
   # configuration information (to avoid serialising all parameters)
-  def select(workers, function, config) do
+  def select(workers, function, config, args) do
     Logger.info("Scheduler: selection with #{length(workers)} workers")
 
     # Get the resources
@@ -54,7 +56,8 @@ defmodule Core.Domain.Scheduler do
         case SchedulingPolicy.select(
                config,
                resources,
-               function
+               function,
+               args
              ) do
           {:ok, wrk} -> {:ok, wrk.name}
           {:error, err} -> {:error, err}
diff --git a/core/lib/core_web/auth.ex b/core/lib/core_web/auth.ex
index 5ca68a2..69909a3 100644
--- a/core/lib/core_web/auth.ex
+++ b/core/lib/core_web/auth.ex
@@ -39,7 +39,7 @@ defmodule CoreWeb.Plug.Authenticate do
       _error ->
         conn
         |> put_status(:unauthorized)
-        |> Phoenix.Controller.put_view(CoreWeb.ErrorView)
+        |> Phoenix.Controller.put_view(CoreWeb.ErrorJSON)
         |> Phoenix.Controller.render(:"401")
         |> halt()
     end
diff --git a/core/test/core/integration/invoke_test.exs b/core/test/core/integration/invoke_test.exs
index 3e960d4..db37e78 100644
--- a/core/test/core/integration/invoke_test.exs
+++ b/core/test/core/integration/invoke_test.exs
@@ -85,7 +85,7 @@ defmodule Core.InvokeTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:error, {:exec_error, "some error"}} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:error, {:exec_error, "some error"}} end)
 
       pars = %InvokeParams{function: function.name, module: module.name}
       assert Invoker.invoke(pars) == {:error, {:exec_error, "some error"}}
@@ -99,7 +99,7 @@ defmodule Core.InvokeTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:error, {:exec_error, "some error"}} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:error, {:exec_error, "some error"}} end)
 
       {:ok, resources} = Core.Telemetry.Metrics.Mock.resources(:worker@localhost)
       concurrent = resources |> Map.get(:concurrent_functions, 0)
@@ -133,7 +133,7 @@ defmodule Core.InvokeTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:core@somewhere, :worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn worker, _, _, _, _ ->
+      |> Mox.expect(:send_invoke, fn worker, _, _, _, _, _ ->
         {:ok, %InvokeResult{result: worker}}
       end)
 
@@ -168,7 +168,7 @@ defmodule Core.InvokeTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:error, :code_not_found, self()} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:error, :code_not_found, self()} end)
 
       Core.Commands.Mock
       |> Mox.expect(:send_invoke_with_code, fn _worker, _handler, function ->
diff --git a/core/test/core_web/integration/controllers/function_controller_test.exs b/core/test/core_web/integration/controllers/function_controller_test.exs
index ac2e699..5ade5e8 100644
--- a/core/test/core_web/integration/controllers/function_controller_test.exs
+++ b/core/test/core_web/integration/controllers/function_controller_test.exs
@@ -453,7 +453,7 @@ defmodule CoreWeb.FunctionControllerTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:ok, %{result: "Hello, World!"}} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:ok, %{result: "Hello, World!"}} end)
 
       conn = post(conn, ~p"/v1/fn/#{module_name}/#{function_name}")
       assert response(conn, 200)
@@ -467,7 +467,7 @@ defmodule CoreWeb.FunctionControllerTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:ok, %{result: "Hello, World!"}} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:ok, %{result: "Hello, World!"}} end)
 
       conn = post(conn, ~p"/v1/fn/#{module_name}/#{function_name}", args: %{name: "World"})
 
@@ -482,7 +482,7 @@ defmodule CoreWeb.FunctionControllerTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:error, :code_not_found, self()} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ -> {:error, :code_not_found, self()} end)
 
       conn = post(conn, ~p"/v1/fn/#{module_name}/#{function_name}")
       assert response(conn, 200)
@@ -519,7 +519,9 @@ defmodule CoreWeb.FunctionControllerTest do
       Core.Cluster.Mock |> Mox.expect(:all_nodes, fn -> [:worker@localhost] end)
 
       Core.Commands.Mock
-      |> Mox.expect(:send_invoke, fn _, _, _, _, _ -> {:error, {:exec_error, "some reason"}} end)
+      |> Mox.expect(:send_invoke, fn _, _, _, _, _, _ ->
+        {:error, {:exec_error, "some reason"}}
+      end)
 
       conn = post(conn, ~p"/v1/fn/#{module_name}/#{function_name}")
       assert response(conn, 422)
diff --git a/data/lib/function_metadata.ex b/data/lib/function_metadata.ex
index 4e9cb0e..68505ec 100644
--- a/data/lib/function_metadata.ex
+++ b/data/lib/function_metadata.ex
@@ -24,5 +24,5 @@ defmodule Data.FunctionMetadata do
           tag: String.t(),
           capacity: integer()
         }
-  defstruct tag: nil, capacity: -1
+  defstruct tag: "", capacity: -1
 end