diff --git a/sdk/src/lib/message/index.js b/sdk/src/lib/message/index.js
index b6e538e41..b85c534ca 100644
--- a/sdk/src/lib/message/index.js
+++ b/sdk/src/lib/message/index.js
@@ -10,7 +10,7 @@ import { uploadMessageWith } from './upload-message.js'
  *
  * @typedef SendMessageArgs
  * @property {string} process
- * @property {string | ArrayBuffer} [data]
+ * @property {string} [data]
  * @property {string} [anchor]
  * @property {{ name: string, value: string }[]} [tags]
  * @property {any} signer
diff --git a/sdk/src/lib/spawn/index.js b/sdk/src/lib/spawn/index.js
index 033de9442..279c27401 100644
--- a/sdk/src/lib/spawn/index.js
+++ b/sdk/src/lib/spawn/index.js
@@ -13,7 +13,7 @@ import { uploadProcessWith } from './upload-process.js'
  * @property {string} scheduler
  * @property {string} signer
  * @property {{ name: string, value: string }[]} [tags]
- * @property {string | ArrayBuffer} [data]
+ * @property {string} [data]
  *
  * @callback SpawnProcess
  * @param {SpawnProcessArgs} args