diff --git a/Cargo.lock b/Cargo.lock
index 84a9a95a..311b98f1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1049,7 +1049,7 @@ dependencies = [
 [[package]]
 name = "ndc-client"
 version = "0.1.0"
-source = "git+http://github.com/hasura/ndc-spec.git?tag=v0.1.0-rc.16#608ecc4b6719753c186a37494bbe95ae26e64f45"
+source = "git+http://github.com/hasura/ndc-spec.git?tag=v0.1.0-rc.18#608ecc4b6719753c186a37494bbe95ae26e64f45"
 dependencies = [
  "async-trait",
  "indexmap 2.1.0",
@@ -1104,7 +1104,7 @@ dependencies = [
 [[package]]
 name = "ndc-test"
 version = "0.1.0"
-source = "git+http://github.com/hasura/ndc-spec.git?tag=v0.1.0-rc.16#608ecc4b6719753c186a37494bbe95ae26e64f45"
+source = "git+http://github.com/hasura/ndc-spec.git?tag=v0.1.0-rc.18#608ecc4b6719753c186a37494bbe95ae26e64f45"
 dependencies = [
  "async-trait",
  "clap",
diff --git a/rust-connector-sdk/Cargo.toml b/rust-connector-sdk/Cargo.toml
index e8b8b649..dd2ebf48 100644
--- a/rust-connector-sdk/Cargo.toml
+++ b/rust-connector-sdk/Cargo.toml
@@ -13,8 +13,8 @@ path = "bin/main.rs"
 
 [dependencies]
 gdc_rust_types = { git = "https://github.com/hasura/gdc_rust_types.git", rev = "3273434" }
-ndc-client = { git = "http://github.com/hasura/ndc-spec.git", tag = "v0.1.0-rc.16" }
-ndc-test = { git = "http://github.com/hasura/ndc-spec.git", tag = "v0.1.0-rc.16" }
+ndc-client = { git = "http://github.com/hasura/ndc-spec.git", tag = "v0.1.0-rc.18" }
+ndc-test = { git = "http://github.com/hasura/ndc-spec.git", tag = "v0.1.0-rc.18" }
 
 async-trait = "^0.1.74"
 axum = "^0.6.20"