diff --git a/agora-bench/Bench.hs b/agora-bench/Bench.hs
index f6dc480..dd03722 100644
--- a/agora-bench/Bench.hs
+++ b/agora-bench/Bench.hs
@@ -1,6 +1,7 @@
 module Bench (Benchmark (..), benchmarkScript, specificationTreeToBenchmarks) where
 
 import Codec.Serialise (serialise)
+import Data.Aeson hiding (Success)
 import Data.ByteString.Lazy qualified as LBS
 import Data.ByteString.Short qualified as SBS
 import Data.List (intercalate)
@@ -35,6 +36,23 @@ data Benchmark = Benchmark
   }
   deriving stock (Show, Eq, Ord)
 
+instance FromJSON Benchmark where
+  parseJSON (Object v) =
+    Benchmark <$> v .: "name"
+      <*> v .: "cpu"
+      <*> v .: "mem"
+      <*> v .: "size"
+  parseJSON _ = mempty
+
+instance ToJSON Benchmark where
+  toJSON (Benchmark name cpu mem size) =
+    object
+      [ "name" .= name
+      , "cpu" .= cpu
+      , "mem" .= mem
+      , "size" .= size
+      ]
+
 benchmarkScript :: String -> Script -> Benchmark
 benchmarkScript name script = Benchmark (pack name) cpu mem size
   where
diff --git a/agora-bench/Main.hs b/agora-bench/Main.hs
index c0dcc3f..c0c47c7 100644
--- a/agora-bench/Main.hs
+++ b/agora-bench/Main.hs
@@ -1,6 +1,8 @@
 module Main (main) where
 
 import Bench (specificationTreeToBenchmarks)
+import Data.Aeson.Text (encodeToLazyText)
+import Data.Text.Lazy.IO as I
 import Spec.AuthorityToken qualified as AuthorityToken
 import Spec.Effect.GovernorMutation qualified as GovernorMutation
 import Spec.Effect.TreasuryWithdrawal qualified as TreasuryWithdrawal
@@ -15,19 +17,20 @@ import Prelude
 
 main :: IO ()
 main = do
-  mapM_ print $
-    specificationTreeToBenchmarks $
-      group
-        "Benchmark"
-        [ group
-            "Effects"
-            [ group "Treasury Withdrawal Effect" TreasuryWithdrawal.specs
-            , group "Governor Mutation Effect" GovernorMutation.specs
-            ]
-        , group "Stake" Stake.specs
-        , group "Proposal" Proposal.specs
-        , group "AuthorityToken" AuthorityToken.specs
-        , group "Treasury" Treasury.specs
-        , group "AuthorityToken" AuthorityToken.specs
-        , group "Governor" Governor.specs
-        ]
+  I.writeFile "bench.json" $
+    encodeToLazyText $
+      specificationTreeToBenchmarks $
+        group
+          "Benchmark"
+          [ group
+              "Effects"
+              [ group "Treasury Withdrawal Effect" TreasuryWithdrawal.specs
+              , group "Governor Mutation Effect" GovernorMutation.specs
+              ]
+          , group "Stake" Stake.specs
+          , group "Proposal" Proposal.specs
+          , group "AuthorityToken" AuthorityToken.specs
+          , group "Treasury" Treasury.specs
+          , group "AuthorityToken" AuthorityToken.specs
+          , group "Governor" Governor.specs
+          ]
diff --git a/agora-spec/Spec/Spec.hs b/agora-spec/Spec/Spec.hs
index a58deac..f7dc14a 100644
--- a/agora-spec/Spec/Spec.hs
+++ b/agora-spec/Spec/Spec.hs
@@ -50,7 +50,7 @@ exists s (Group name st) = or (exists s <$> st) || s == name
 
 group :: String -> [SpecificationTree] -> SpecificationTree
 group name st
-  | or $ exists name <$> st = error "Name already exists"
+  | or $ exists name <$> st = error $ "Name already exists: " <> name
   | otherwise = Group name st
 
 getSpecification :: String -> SpecificationTree -> Maybe Specification
diff --git a/bench.json b/bench.json
new file mode 100644
index 0000000..2a045ee
--- /dev/null
+++ b/bench.json
@@ -0,0 +1 @@
+[{"cpu":340268715,"mem":724428,"name":"Benchmark/Effects/Treasury Withdrawal Effect/effect/Simple","size":3050},{"cpu":570029812,"mem":1211300,"name":"Benchmark/Effects/Treasury Withdrawal Effect/effect/Simple with multiple treasuries ","size":3377},{"cpu":502351827,"mem":1071087,"name":"Benchmark/Effects/Treasury Withdrawal Effect/effect/Mixed Assets","size":3242},{"cpu":103054094,"mem":227264,"name":"Benchmark/Effects/Governor Mutation Effect/validator/valid new governor datum/governor validator should pass","size":7467},{"cpu":126696096,"mem":263635,"name":"Benchmark/Effects/Governor Mutation Effect/validator/valid new governor datum/effect validator should pass","size":3293},{"cpu":147898986,"mem":329450,"name":"Benchmark/Stake/policy/stakeCreation","size":2265},{"cpu":261845190,"mem":576377,"name":"Benchmark/Stake/validator/stakeDepositWithdraw deposit","size":3829},{"cpu":261845190,"mem":576377,"name":"Benchmark/Stake/validator/stakeDepositWithdraw withdraw","size":3821},{"cpu":34571405,"mem":70066,"name":"Benchmark/Proposal/policy/proposalCreation","size":1549},{"cpu":242652509,"mem":511783,"name":"Benchmark/Proposal/validator/cosignature/proposal","size":5247},{"cpu":183513647,"mem":395070,"name":"Benchmark/Proposal/validator/cosignature/stake","size":4366},{"cpu":240358004,"mem":492704,"name":"Benchmark/Proposal/validator/voting/proposal","size":5255},{"cpu":154841851,"mem":329311,"name":"Benchmark/Proposal/validator/voting/stake","size":4419},{"cpu":25177457,"mem":55883,"name":"Benchmark/AuthorityToken/singleAuthorityTokenBurned/Correct simple","size":806},{"cpu":40266637,"mem":88241,"name":"Benchmark/AuthorityToken/singleAuthorityTokenBurned/Correct many inputs","size":900},{"cpu":37343572,"mem":79744,"name":"Benchmark/Treasury/Validator/Positive/Allows for effect changes","size":1841},{"cpu":25177457,"mem":55883,"name":"Benchmark/AuthorityToken/singleAuthorityTokenBurned/Correct simple","size":806},{"cpu":40266637,"mem":88241,"name":"Benchmark/AuthorityToken/singleAuthorityTokenBurned/Correct many inputs","size":900},{"cpu":57648280,"mem":119961,"name":"Benchmark/Governor/policy/GST minting","size":1836},{"cpu":309839049,"mem":649395,"name":"Benchmark/Governor/validator/proposal creation","size":7994},{"cpu":429394828,"mem":928681,"name":"Benchmark/Governor/validator/GATs minting","size":8113},{"cpu":100243054,"mem":221538,"name":"Benchmark/Governor/validator/mutate governor state","size":7540}]
\ No newline at end of file