diff --git a/src/core/prompts/tools/native-tools/browser_action.ts b/src/core/prompts/tools/native-tools/browser_action.ts
index 0a13d168f9e..2ff4b1cf9b8 100644
--- a/src/core/prompts/tools/native-tools/browser_action.ts
+++ b/src/core/prompts/tools/native-tools/browser_action.ts
@@ -22,7 +22,7 @@ export default {
 	function: {
 		name: "browser_action",
 		description: BROWSER_ACTION_DESCRIPTION,
-		strict: true,
+		strict: false,
 		parameters: {
 			type: "object",
 			properties: {
diff --git a/src/core/prompts/tools/native-tools/read_file.ts b/src/core/prompts/tools/native-tools/read_file.ts
index 3a5dfd081bc..bf43f26c8af 100644
--- a/src/core/prompts/tools/native-tools/read_file.ts
+++ b/src/core/prompts/tools/native-tools/read_file.ts
@@ -55,6 +55,10 @@ export function createReadFileTool(partialReadsEnabled: boolean = true): OpenAI.
 		}
 	}
 
+	// When using strict mode, ALL properties must be in the required array
+	// Optional properties are handled by having type: ["...", "null"]
+	const fileRequiredProperties = partialReadsEnabled ? ["path", "line_ranges"] : ["path"]
+
 	return {
 		type: "function",
 		function: {
@@ -70,7 +74,7 @@ export function createReadFileTool(partialReadsEnabled: boolean = true): OpenAI.
 						items: {
 							type: "object",
 							properties: fileProperties,
-							required: ["path"],
+							required: fileRequiredProperties,
 							additionalProperties: false,
 						},
 						minItems: 1,