diff --git a/src/client.rs b/src/client.rs
new file mode 100644
index 0000000..146e86e
--- /dev/null
+++ b/src/client.rs
@@ -0,0 +1 @@
+pub mod mercadopago;
diff --git a/src/client/mercadopago.rs b/src/client/mercadopago.rs
new file mode 100644
index 0000000..0fb6569
--- /dev/null
+++ b/src/client/mercadopago.rs
@@ -0,0 +1,74 @@
+use reqwest::Method;
+use thiserror::Error;
+
+use crate::API_BASE_URL;
+
+pub struct MercadoPagoClient {
+    access_token: String,
+    client_http: reqwest::Client,
+}
+
+#[derive(Debug, Error)]
+pub enum CredentialsError {
+    #[error("Credentials are requires")]
+    BadRequest,
+    #[error("Credentials are invalid")]
+    Unauthorized,
+    #[error("Not found")]
+    NotFound,
+    #[error("Internal Server Error")]
+    InternalServerError,
+
+    #[error("Error while sending request: {0}")]
+    RequestError(#[from] reqwest::Error),
+}
+
+impl MercadoPagoClient {
+    pub fn create_with_access_token(access_token: impl ToString) -> Self {
+        Self {
+            access_token: access_token.to_string(),
+            client_http: reqwest::Client::new(),
+        }
+    }
+
+    pub fn start_request(
+        &self,
+        method: reqwest::Method,
+        path: impl ToString,
+    ) -> reqwest::RequestBuilder {
+        self.client_http
+            .request(method, format!("{API_BASE_URL}{}", path.to_string()))
+            .bearer_auth(&self.access_token)
+    }
+
+    pub async fn check_credentials(&self) -> Result<(), CredentialsError> {
+        let response = self
+            .start_request(Method::GET, "/v1/payment_methods")
+            .send()
+            .await?;
+
+        match response.status().as_u16() {
+            200 => Ok(()),
+            400 => Err(CredentialsError::BadRequest),
+            401 => Err(CredentialsError::Unauthorized),
+            404 => Err(CredentialsError::NotFound),
+            _ => Err(CredentialsError::InternalServerError),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::MercadoPagoClient;
+
+    #[tokio::test]
+    async fn create_client() {
+        dotenvy::dotenv().ok();
+
+        let client = MercadoPagoClient::create_with_access_token(
+            std::env::var("MERCADO_PAGO_ACCESS").unwrap(),
+        );
+
+        assert!(client.check_credentials().await.is_ok())
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..a9d35bd
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,3 @@
+pub mod client;
+
+pub static API_BASE_URL: &str = "https://api.mercadopago.com";