fix(coding-agent/tools): deduplicate JTD primitive detection

packages/coding-agent/src/tools/jtd-to-json-schema.ts

@@ -135,6 +135,18 @@ function convertSchema(schema: unknown): unknown {
 	return {};
 }
 
+const jtdOnlyPrimitiveTypes: Record<string, true> = {
+	timestamp: true,
+	float32: true,
+	float64: true,
+	int8: true,
+	uint8: true,
+	int16: true,
+	uint16: true,
+	int32: true,
+	uint32: true,
+};
+
 /**
  * Detect if a schema is JTD format (vs JSON Schema).
  *
@@ -156,11 +168,8 @@ export function isJTDSchema(schema: unknown): boolean {
 	if ("ref" in obj) return true;
 
 	// JTD type primitives (JSON Schema doesn't have int32, float64, etc.)
-	if ("type" in obj) {
-		const jtdPrimitives = ["timestamp", "float32", "float64", "int8", "uint8", "int16", "uint16", "int32", "uint32"];
-		if (jtdPrimitives.includes(obj.type as string)) {
-			return true;
-		}
+	if (typeof obj.type === "string" && Object.hasOwn(jtdOnlyPrimitiveTypes, obj.type)) {
+		return true;
 	}
 
 	// JTD properties form without type: "object" (JSON Schema requires it)
@@ -171,18 +180,6 @@ export function isJTDSchema(schema: unknown): boolean {
 	return false;
 }
 
-const jtdOnlyPrimitiveTypes: Record<string, true> = {
-	timestamp: true,
-	float32: true,
-	float64: true,
-	int8: true,
-	uint8: true,
-	int16: true,
-	uint16: true,
-	int32: true,
-	uint32: true,
-};
-
 function isUnambiguousJTDSchema(schema: unknown): boolean {
 	if (!isRecord(schema)) return false;
 

packages/coding-agent/test/tools/jtd-to-json-schema.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "bun:test";
-import { jtdToJsonSchema } from "@oh-my-pi/pi-coding-agent/tools/jtd-to-json-schema";
+import { isJTDSchema, jtdToJsonSchema } from "@oh-my-pi/pi-coding-agent/tools/jtd-to-json-schema";
 
 describe("jtdToJsonSchema", () => {
 	it("converts JTD elements and int32 primitives into JSON Schema", () => {
@@ -33,6 +33,8 @@ describe("jtdToJsonSchema", () => {
 			required: ["results"],
 			additionalProperties: false,
 		});
+		expect(jtdToJsonSchema({ type: "int32" })).toEqual({ type: "integer" });
+		expect(isJTDSchema({ type: "int32" })).toBe(true);
 	});
 
 	it("normalizes nested JTD fragments inside JSON Schema nodes", () => {