diff --git a/examples/call.graphql b/examples/call.graphql
index b97730ce57..8d49788d81 100644
--- a/examples/call.graphql
+++ b/examples/call.graphql
@@ -11,7 +11,7 @@ type Post {
 
 type Query {
   user(id: Int!): User @http(path: "/users/{{args.id}}")
-  firstUser: User @call(query: "user", args: {id: "1"})
+  firstUser: User @call(query: "user", args: {id: 1})
   postFromUser(userId: Int!): [Post] @http(path: "/posts?userId={{args.userId}}")
 }
 
diff --git a/src/blueprint/operators/call.rs b/src/blueprint/operators/call.rs
index a33cbedf66..d9506e4d5d 100644
--- a/src/blueprint/operators/call.rs
+++ b/src/blueprint/operators/call.rs
@@ -1,5 +1,7 @@
 use std::collections::hash_map::Iter;
 
+use serde_json::Value;
+
 use crate::blueprint::*;
 use crate::config;
 use crate::config::{Field, GraphQLOperationType, KeyValues};
@@ -8,7 +10,7 @@ use crate::mustache::{Mustache, Segment};
 use crate::try_fold::TryFold;
 use crate::valid::{Valid, Validator};
 
-fn find_value<'a>(args: &'a Iter<'a, String, String>, key: &'a String) -> Option<&'a String> {
+fn find_value<'a>(args: &'a Iter<'a, String, Value>, key: &'a String) -> Option<&'a Value> {
     args.clone()
         .find_map(|(k, value)| if k == key { Some(value) } else { None })
 }
@@ -94,7 +96,7 @@ pub fn compile_call(
 }
 
 fn replace_key_values<'a>(
-    args: &'a Iter<'a, String, String>,
+    args: &'a Iter<'a, String, Value>,
 ) -> impl Fn(KeyValues) -> KeyValues + 'a {
     |key_values| {
         KeyValues(
@@ -106,7 +108,7 @@ fn replace_key_values<'a>(
     }
 }
 
-fn replace_string<'a>(args: &'a Iter<'a, String, String>) -> impl Fn(String) -> String + 'a {
+fn replace_string<'a>(args: &'a Iter<'a, String, Value>) -> impl Fn(String) -> String + 'a {
     |str| {
         let mustache = Mustache::parse(&str).unwrap();
 
@@ -129,7 +131,7 @@ fn get_type_and_field(call: &config::Call) -> Option<(String, String)> {
 fn get_field_and_field_name<'a>(
     call: &'a config::Call,
     config_module: &'a ConfigModule,
-) -> Valid<(&'a Field, String, Iter<'a, String, String>), String> {
+) -> Valid<(&'a Field, String, Iter<'a, String, Value>), String> {
     Valid::from_option(
         get_type_and_field(call),
         "call must have query or mutation".to_string(),
@@ -151,7 +153,7 @@ fn get_field_and_field_name<'a>(
     })
 }
 
-fn replace_mustache_value(value: &Mustache, args: &Iter<'_, String, String>) -> Mustache {
+fn replace_mustache_value(value: &Mustache, args: &Iter<'_, String, Value>) -> Mustache {
     value
         .get_segments()
         .iter()
@@ -160,7 +162,7 @@ fn replace_mustache_value(value: &Mustache, args: &Iter<'_, String, String>) ->
             Segment::Expression(expression) => {
                 if expression[0] == "args" {
                     let value = find_value(args, &expression[1]).unwrap();
-                    let item = Mustache::parse(value).unwrap();
+                    let item = Mustache::parse(value.to_string().as_str()).unwrap();
 
                     let expression = item.get_segments().first().unwrap().to_owned().to_owned();
 
diff --git a/src/config/config.rs b/src/config/config.rs
index f4579cc7f6..3762810e2f 100644
--- a/src/config/config.rs
+++ b/src/config/config.rs
@@ -608,7 +608,7 @@ pub struct Call {
     pub mutation: Option<String>,
 
     /// The arguments of the field on the `Query` type that you want to call. For instance `{id: "{{value.userId}}"}`.
-    pub args: HashMap<String, String>,
+    pub args: HashMap<String, Value>,
 }
 
 #[derive(Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema)]
diff --git a/tests/execution/call-mutation.md b/tests/execution/call-mutation.md
index 0b3ba8fa03..adc22a41b4 100644
--- a/tests/execution/call-mutation.md
+++ b/tests/execution/call-mutation.md
@@ -24,10 +24,12 @@ type Mutation {
   attachPostToUser(userId: Int!, postId: Int!): User
     @http(body: "{\"postId\":{{args.postId}}}", method: "PATCH", path: "/users/{{args.userId}}")
   attachPostToFirstUser(postId: Int!): User
-    @call(mutation: "attachPostToUser", args: {postId: "{{args.postId}}", userId: "1"})
+    @call(mutation: "attachPostToUser", args: {postId: "{{args.postId}}", userId: 1})
   insertPost(input: PostInput): Post @http(body: "{{args.input}}", method: "POST", path: "/posts")
+  insertMockedPost: Post
+    @call(mutation: "insertPost", args: {input: {body: "post-body", title: "post-title", userId: 1}})
   insertPostToFirstUser(input: PostInputWithoutUserId): Post
-    @call(mutation: "insertPostToUser", args: {input: "{{args.input}}", userId: "1"})
+    @call(mutation: "insertPostToUser", args: {input: "{{args.input}}", userId: 1})
   insertPostToUser(input: PostInputWithoutUserId!, userId: Int!): Post
     @http(body: "{{args.input}}", method: "POST", path: "/users/{{args.userId}}/posts")
 }
@@ -132,4 +134,8 @@ type User {
   url: http://localhost:8080/graphql
   body:
     query: 'mutation { insertPostToFirstUser(input: { body: "post-body", title: "post-title" }) { body } }'
+- method: POST
+  url: http://localhost:8080/graphql
+  body:
+    query: "mutation { insertMockedPost { body } }"
 ```
diff --git a/tests/execution/call-operator.md b/tests/execution/call-operator.md
index aa74ce0771..d28121ef07 100644
--- a/tests/execution/call-operator.md
+++ b/tests/execution/call-operator.md
@@ -106,7 +106,7 @@ type Post {
   userGraphQL: User @call(query: "userGraphQL", args: {id: "{{value.userId}}"})
   userGraphQLHeaders: User @call(query: "userGraphQLHeaders", args: {id: "{{value.userId}}"})
   news: NewsData! @call(query: "news", args: {})
-  newsWithPortArg: NewsData! @call(query: "news", args: {port: "50051"})
+  newsWithPortArg: NewsData! @call(query: "news", args: {port: 50051})
 }
 ```
 
diff --git a/tests/snapshots/execution_spec__call-mutation.md_assert_4.snap b/tests/snapshots/execution_spec__call-mutation.md_assert_4.snap
new file mode 100644
index 0000000000..7ca89a4e51
--- /dev/null
+++ b/tests/snapshots/execution_spec__call-mutation.md_assert_4.snap
@@ -0,0 +1,17 @@
+---
+source: tests/execution_spec.rs
+expression: response
+---
+{
+  "status": 200,
+  "headers": {
+    "content-type": "application/json"
+  },
+  "body": {
+    "data": {
+      "insertMockedPost": {
+        "body": "post-body"
+      }
+    }
+  }
+}
diff --git a/tests/snapshots/execution_spec__call-mutation.md_client.snap b/tests/snapshots/execution_spec__call-mutation.md_client.snap
index 2e85113bd6..1e39f82dd5 100644
--- a/tests/snapshots/execution_spec__call-mutation.md_client.snap
+++ b/tests/snapshots/execution_spec__call-mutation.md_client.snap
@@ -5,6 +5,7 @@ expression: client
 type Mutation {
   attachPostToFirstUser(postId: Int!): User
   attachPostToUser(postId: Int!, userId: Int!): User
+  insertMockedPost: Post
   insertPost(input: PostInput): Post
   insertPostToFirstUser(input: PostInputWithoutUserId): Post
   insertPostToUser(input: PostInputWithoutUserId!, userId: Int!): Post
diff --git a/tests/snapshots/execution_spec__call-mutation.md_merged.snap b/tests/snapshots/execution_spec__call-mutation.md_merged.snap
index c7d45da7b2..f3d0039c7c 100644
--- a/tests/snapshots/execution_spec__call-mutation.md_merged.snap
+++ b/tests/snapshots/execution_spec__call-mutation.md_merged.snap
@@ -20,10 +20,11 @@ input PostInputWithoutUserId {
 }
 
 type Mutation {
-  attachPostToFirstUser(postId: Int!): User @call(mutation: "attachPostToUser", args: {postId: "{{args.postId}}", userId: "1"})
+  attachPostToFirstUser(postId: Int!): User @call(mutation: "attachPostToUser", args: {postId: "{{args.postId}}", userId: 1})
   attachPostToUser(postId: Int!, userId: Int!): User @http(body: "{\"postId\":{{args.postId}}}", method: "PATCH", path: "/users/{{args.userId}}")
+  insertMockedPost: Post @call(mutation: "insertPost", args: {input: {body: "post-body", title: "post-title", userId: 1}})
   insertPost(input: PostInput): Post @http(body: "{{args.input}}", method: "POST", path: "/posts")
-  insertPostToFirstUser(input: PostInputWithoutUserId): Post @call(mutation: "insertPostToUser", args: {input: "{{args.input}}", userId: "1"})
+  insertPostToFirstUser(input: PostInputWithoutUserId): Post @call(mutation: "insertPostToUser", args: {input: "{{args.input}}", userId: 1})
   insertPostToUser(input: PostInputWithoutUserId!, userId: Int!): Post @http(body: "{{args.input}}", method: "POST", path: "/users/{{args.userId}}/posts")
 }
 
diff --git a/tests/snapshots/execution_spec__call-operator.md_merged.snap b/tests/snapshots/execution_spec__call-operator.md_merged.snap
index c09e5ac7bd..5c064fb12c 100644
--- a/tests/snapshots/execution_spec__call-operator.md_merged.snap
+++ b/tests/snapshots/execution_spec__call-operator.md_merged.snap
@@ -21,7 +21,7 @@ type Post {
   body: String
   id: Int
   news: NewsData! @call(query: "news", args: {})
-  newsWithPortArg: NewsData! @call(query: "news", args: {port: "50051"})
+  newsWithPortArg: NewsData! @call(query: "news", args: {port: 50051})
   title: String
   user: User @call(query: "user", args: {id: "{{value.userId}}"})
   user1: User @call(query: "user1", args: {})