fix(agents): remove unsupported JSON Schema keywords for Cloud Code Assist API

Cloud Code Assist API requires strict JSON Schema draft 2020-12 compliance
and rejects keywords like patternProperties, additionalProperties, $schema,
$id, $ref, $defs, and definitions.

This extends cleanSchemaForGemini to:
- Remove all unsupported keywords from tool schemas
- Add oneOf literal flattening (matching existing anyOf behavior)
- Add test to verify no unsupported keywords remain in tool schemas

src/agents/pi-tools.test.ts

@@ -331,4 +331,52 @@ describe("createClawdbotCodingTools", () => {
     expect(tools.some((tool) => tool.name === "Bash")).toBe(true);
     expect(tools.some((tool) => tool.name === "browser")).toBe(false);
   });
+
+  it("removes unsupported JSON Schema keywords for Cloud Code Assist API compatibility", () => {
+    const tools = createClawdbotCodingTools();
+
+    // Helper to recursively check schema for unsupported keywords
+    const unsupportedKeywords = new Set([
+      "patternProperties",
+      "additionalProperties",
+      "$schema",
+      "$id",
+      "$ref",
+      "$defs",
+      "definitions",
+    ]);
+
+    const findUnsupportedKeywords = (
+      schema: unknown,
+      path: string,
+    ): string[] => {
+      const found: string[] = [];
+      if (!schema || typeof schema !== "object") return found;
+      if (Array.isArray(schema)) {
+        schema.forEach((item, i) => {
+          found.push(...findUnsupportedKeywords(item, `${path}[${i}]`));
+        });
+        return found;
+      }
+      for (const [key, value] of Object.entries(
+        schema as Record<string, unknown>,
+      )) {
+        if (unsupportedKeywords.has(key)) {
+          found.push(`${path}.${key}`);
+        }
+        if (value && typeof value === "object") {
+          found.push(...findUnsupportedKeywords(value, `${path}.${key}`));
+        }
+      }
+      return found;
+    };
+
+    for (const tool of tools) {
+      const violations = findUnsupportedKeywords(
+        tool.parameters,
+        `${tool.name}.parameters`,
+      );
+      expect(violations).toEqual([]);
+    }
+  });
 });

src/agents/pi-tools.ts

@@ -195,12 +195,24 @@ function tryFlattenLiteralAnyOf(
   return null;
 }
 
+// Keywords that Cloud Code Assist API rejects (not compliant with their JSON Schema subset)
+const UNSUPPORTED_SCHEMA_KEYWORDS = new Set([
+  "patternProperties",
+  "additionalProperties",
+  "$schema",
+  "$id",
+  "$ref",
+  "$defs",
+  "definitions",
+]);
+
 function cleanSchemaForGemini(schema: unknown): unknown {
   if (!schema || typeof schema !== "object") return schema;
   if (Array.isArray(schema)) return schema.map(cleanSchemaForGemini);
 
   const obj = schema as Record<string, unknown>;
   const hasAnyOf = "anyOf" in obj && Array.isArray(obj.anyOf);
+  const hasOneOf = "oneOf" in obj && Array.isArray(obj.oneOf);
 
   // Try to flatten anyOf of literals to a single enum BEFORE processing
   // This handles Type.Union([Type.Literal("a"), Type.Literal("b")]) patterns
@@ -221,14 +233,28 @@ function cleanSchemaForGemini(schema: unknown): unknown {
     }
   }
 
+  // Try to flatten oneOf of literals similarly
+  if (hasOneOf) {
+    const flattened = tryFlattenLiteralAnyOf(obj.oneOf as unknown[]);
+    if (flattened) {
+      const result: Record<string, unknown> = {
+        type: flattened.type,
+        enum: flattened.enum,
+      };
+      for (const key of ["description", "title", "default", "examples"]) {
+        if (key in obj && obj[key] !== undefined) {
+          result[key] = obj[key];
+        }
+      }
+      return result;
+    }
+  }
+
   const cleaned: Record<string, unknown> = {};
 
   for (const [key, value] of Object.entries(obj)) {
-    // Skip unsupported schema features for Gemini:
-    // - patternProperties: not in OpenAPI 3.0 subset
-    // - const: convert to enum with single value instead
-    if (key === "patternProperties") {
-      // Gemini doesn't support patternProperties - skip it
+    // Skip keywords that Cloud Code Assist API doesn't support
+    if (UNSUPPORTED_SCHEMA_KEYWORDS.has(key)) {
       continue;
     }
 
@@ -238,8 +264,8 @@ function cleanSchemaForGemini(schema: unknown): unknown {
       continue;
     }
 
-    // Skip 'type' if we have 'anyOf' — Gemini doesn't allow both
-    if (key === "type" && hasAnyOf) {
+    // Skip 'type' if we have 'anyOf' or 'oneOf' — Gemini doesn't allow both
+    if (key === "type" && (hasAnyOf || hasOneOf)) {
       continue;
     }
 
@@ -261,13 +287,6 @@ function cleanSchemaForGemini(schema: unknown): unknown {
     } else if (key === "allOf" && Array.isArray(value)) {
       // Clean each allOf variant
       cleaned[key] = value.map((variant) => cleanSchemaForGemini(variant));
-    } else if (
-      key === "additionalProperties" &&
-      value &&
-      typeof value === "object"
-    ) {
-      // Recursively clean additionalProperties schema
-      cleaned[key] = cleanSchemaForGemini(value);
     } else {
       cleaned[key] = value;
     }