diff --git a/webmcp/declarative/getTools-declarative-schema.https.html b/webmcp/declarative/getTools-declarative-schema.https.html
index 66f79afa423bb3..d667084fa570f5 100644
--- a/webmcp/declarative/getTools-declarative-schema.https.html
+++ b/webmcp/declarative/getTools-declarative-schema.https.html
@@ -35,7 +35,7 @@
       required: ["query"]
     };
 
-    const tool = await waitForFormToolSchemaToMatch(expected_schema_obj);
+    const tool = await waitForFormToolSchemaToMatch(JSON.stringify(expected_schema_obj));
 
     assert_equals(tool.name, "search_tool", "Tool name matches");
     assert_equals(tool.description, "Search the web", "Tool description matches");
diff --git a/webmcp/declarative/toolchange-on-control-add-remove.https.html b/webmcp/declarative/toolchange-on-control-add-remove.https.html
index 3612d3ac69ca35..4a794c188fd299 100644
--- a/webmcp/declarative/toolchange-on-control-add-remove.https.html
+++ b/webmcp/declarative/toolchange-on-control-add-remove.https.html
@@ -17,7 +17,7 @@
     const form = document.getElementById('f1');
 
     // Wait for the baseline form schema.
-    await waitForFormToolSchemaToMatch({"type":"object","properties":{"input_name":{"type":"string"}},"required":[]});
+    await waitForFormToolSchemaToMatch(`{"type":"object","properties":{"input_name":{"type":"string"}},"required":[]}`);
 
     // Test adding an input
     const i = document.createElement('input');
@@ -25,12 +25,12 @@
     i.name = 'new_input';
     i.id = 'new_input';
     form.appendChild(i);
-    await waitForFormToolSchemaToMatch({"type":"object","properties":{"input_name":{"type":"string"},"new_input":{"type":"string"}},"required":[]});
+    await waitForFormToolSchemaToMatch(`{"type":"object","properties":{"input_name":{"type":"string"},"new_input":{"type":"string"}},"required":[]}`);
 
     // Test removing an input
     const newInput = document.getElementById('new_input');
     form.removeChild(newInput);
-    await waitForFormToolSchemaToMatch({"type":"object","properties":{"input_name":{"type":"string"}},"required":[]});
+    await waitForFormToolSchemaToMatch(`{"type":"object","properties":{"input_name":{"type":"string"}},"required":[]}`);
   }, "Test that toolchange event fires when controls are added or removed");
 </script>
 </body>
diff --git a/webmcp/imperative/exposedTo-cross-origin-child.https.html b/webmcp/imperative/exposedTo-cross-origin-child.https.html
index c2fcda8204bc8b..1e9064c4030984 100644
--- a/webmcp/imperative/exposedTo-cross-origin-child.https.html
+++ b/webmcp/imperative/exposedTo-cross-origin-child.https.html
@@ -44,7 +44,7 @@
   assert_true(toolsAreEqual(tool, {
     name: 'parent_tool_exposed',
     description: 'Parent tool exposed to child',
-    inputSchema: { type: 'object', properties: { query: { type: 'string' } } },
+    inputSchema: JSON.stringify({ type: 'object', properties: { query: { type: 'string' } } }),
     origin: self.origin
   }), 'Tool details should match');
 
@@ -104,7 +104,7 @@
   assert_true(toolsAreEqual(tool, {
     name: 'iframe_tool_exposed',
     description: 'Iframe tool exposed to parent',
-    inputSchema: { type: 'object', properties: { query: { type: 'string' } } },
+    inputSchema: JSON.stringify({ type: 'object', properties: { query: { type: 'string' } } }),
     origin: host_info.HTTPS_REMOTE_ORIGIN
   }), 'Tool details should match');
 
diff --git a/webmcp/imperative/exposedTo-defaults-same-origin.https.html b/webmcp/imperative/exposedTo-defaults-same-origin.https.html
index 93d0e5203bed28..43f827fb0ca302 100644
--- a/webmcp/imperative/exposedTo-defaults-same-origin.https.html
+++ b/webmcp/imperative/exposedTo-defaults-same-origin.https.html
@@ -41,7 +41,7 @@
   assert_true(toolsAreEqual(tool, {
     name: 'parent_tool_default',
     description: 'Parent tool with default exposure',
-    inputSchema: { type: 'object', properties: { query: { type: 'string' } } },
+    inputSchema: JSON.stringify({ type: 'object', properties: { query: { type: 'string' } } }),
     annotations: { readOnlyHint: true, untrustedContentHint: false },
     origin: self.origin
   }), 'Tool details should match');
@@ -90,7 +90,7 @@
   assert_true(toolsAreEqual(tool, {
     name: 'parent_tool_empty',
     description: 'Parent tool with empty exposedTo',
-    inputSchema: { type: 'object', properties: { query: { type: 'string' } } },
+    inputSchema: JSON.stringify({ type: 'object', properties: { query: { type: 'string' } } }),
     origin: self.origin
   }), 'Tool details should match');
 
diff --git a/webmcp/imperative/exposedTo-multiple-children.https.html b/webmcp/imperative/exposedTo-multiple-children.https.html
index 8f7715716f7db5..0ef7377c017080 100644
--- a/webmcp/imperative/exposedTo-multiple-children.https.html
+++ b/webmcp/imperative/exposedTo-multiple-children.https.html
@@ -69,7 +69,7 @@
   assert_true(toolsAreEqual(tool, {
     name: 'tool_b_to_c',
     description: 'Tool B exposed to C',
-    inputSchema: { type: 'object', properties: { query: { type: 'string' } } },
+    inputSchema: JSON.stringify({ type: 'object', properties: { query: { type: 'string' } } }),
     origin: origin_b
   }), 'Tool details should match');
 
diff --git a/webmcp/imperative/getTools-imperative-schema.https.html b/webmcp/imperative/getTools-imperative-schema.https.html
index 37e4b5bc2b2590..4526326d936ab1 100644
--- a/webmcp/imperative/getTools-imperative-schema.https.html
+++ b/webmcp/imperative/getTools-imperative-schema.https.html
@@ -41,23 +41,25 @@
     assert_equals(registeredTool.description, "Search the web", "Tool description matches registered tool");
 
     assert_true(!!registeredTool.inputSchema, "inputSchema should be non-empty");
-    assert_equals(registeredTool.inputSchema.type, "object", "Schema should be an object");
+    const schema = JSON.parse(registeredTool.inputSchema);
+
+    assert_equals(schema.type, "object", "Schema should be an object");
 
     // 'query' property validation (required string)
-    assert_true("query" in registeredTool.inputSchema.properties, "Schema should contain 'query' property");
-    assert_equals(registeredTool.inputSchema.properties.query.type, "string", "Query property type should be string");
-    assert_equals(registeredTool.inputSchema.properties.query.description, "The search query", "Query property description is correct");
-    assert_array_equals(registeredTool.inputSchema.required, ["query"], "Query should be a required property");
+    assert_true("query" in schema.properties, "Schema should contain 'query' property");
+    assert_equals(schema.properties.query.type, "string", "Query property type should be string");
+    assert_equals(schema.properties.query.description, "The search query", "Query property description is correct");
+    assert_array_equals(schema.required, ["query"], "Query should be a required property");
 
     // 'limit' property validation (optional number)
-    assert_true("limit" in registeredTool.inputSchema.properties, "Schema should contain 'limit' property");
-    assert_equals(registeredTool.inputSchema.properties.limit.type, "number", "Limit property type should be number");
-    assert_equals(registeredTool.inputSchema.properties.limit.description, "Max results count", "Limit property description is correct");
+    assert_true("limit" in schema.properties, "Schema should contain 'limit' property");
+    assert_equals(schema.properties.limit.type, "number", "Limit property type should be number");
+    assert_equals(schema.properties.limit.description, "Max results count", "Limit property description is correct");
 
     // 'safe_search' property validation (optional boolean)
-    assert_true("safe_search" in registeredTool.inputSchema.properties, "Schema should contain 'safe_search' property");
-    assert_equals(registeredTool.inputSchema.properties.safe_search.type, "boolean", "safe_search property type should be boolean");
-    assert_equals(registeredTool.inputSchema.properties.safe_search.description, "Enable safe search filtering", "safe_search property description is correct");
+    assert_true("safe_search" in schema.properties, "Schema should contain 'safe_search' property");
+    assert_equals(schema.properties.safe_search.type, "boolean", "safe_search property type should be boolean");
+    assert_equals(schema.properties.safe_search.description, "Enable safe search filtering", "safe_search property description is correct");
   }, "Test that getTools() returns the correct inputSchema for an imperative tool");
 </script>
 </body>
diff --git a/webmcp/imperative/resources/helpers.js b/webmcp/imperative/resources/helpers.js
index 63c1ff5a64c3a0..426548ca93348e 100644
--- a/webmcp/imperative/resources/helpers.js
+++ b/webmcp/imperative/resources/helpers.js
@@ -20,11 +20,8 @@ function toolsAreEqual(actual, expected) {
   if (actual.description !== expected.description) {
     return `descriptions are unequal: ${actual.description} !== ${expected.description}`;
   }
-  if (JSON.stringify(actual.inputSchema) !==
-      JSON.stringify(expected.inputSchema)) {
-    return `inputSchemas are unequal: ${
-        JSON.stringify(
-            actual.inputSchema)} !== ${JSON.stringify(expected.inputSchema)}`;
+  if (actual.inputSchema !== expected.inputSchema) {
+    return `inputSchemas are unequal: ${actual.inputSchemas} !== ${expected.inputSchemas}`;
   }
   if (actual.origin !== expected.origin) {
     return `origins are unequal: ${actual.origin} !== ${expected.origin}`;
diff --git a/webmcp/resources/helpers.js b/webmcp/resources/helpers.js
index d02d1facd41d6c..aae7894532ed3f 100644
--- a/webmcp/resources/helpers.js
+++ b/webmcp/resources/helpers.js
@@ -18,23 +18,17 @@ async function waitForTool(name) {
   });
 }
 
-// Wait for the active WebMCP tool's input schema to match the expected schema.
+// Wait for the active WebMCP tool's input schema to match the expected schema string.
 async function waitForFormToolSchemaToMatch(expected_schema) {
-  const isMatch = (tool) => {
-    if (!tool)
-      return false;
-    return JSON.stringify(tool.inputSchema) === JSON.stringify(expected_schema);
-  };
-
   const [tool] = await document.modelContext.getTools();
-  if (isMatch(tool)) {
+  if (tool && tool.inputSchema === expected_schema) {
     return tool;
   }
   return new Promise(resolve => {
     const ac = new AbortController();
     document.modelContext.addEventListener('toolchange', async e => {
       const [tool] = await document.modelContext.getTools();
-      if (isMatch(tool)) {
+      if (tool && tool.inputSchema === expected_schema) {
         resolve(tool);
         ac.abort();
       }