refactor+test(ai): #1c review — extract emit locals + cover STI symmetry & non-STI invariant

code-simplifier: hoist the record<Entity> Omit/arg ternaries into
recordInputOmit/recordArg locals (emitted output byte-identical).
code-reviewer nits: assert the summarize record path symmetrically, and
assert the non-STI record helper keeps Omit<LlmCallInput,"llmRequest"> with
no callType omission. 8/8 trace tests pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: dmealing

server/typescript/packages/codegen-ts/src/generators/trace-helper-file.ts

@@ -90,6 +90,11 @@ export const traceHelperFile = function traceHelperFile(opts?: TraceHelperOpts):
       const sti = tphPin !== undefined;
       const callTypeValue = sti ? tphPin.value : entityName;
 
+      // Emitted record<Entity> fragments: the keys Omit'd from the caller input,
+      // and the first argument passed to recordLlmCall.
+      const recordInputOmit = sti ? `"llmRequest" | "callType"` : `"llmRequest"`;
+      const recordArg = sti ? `{ ...input, callType: ${JSON.stringify(callTypeValue)} }` : `input`;
+
       // Derive the parse format from the prompt's @format attr.
       // "xml" → Format.XML; absent or any other value → Format.JSON.
       const promptFormat = prompt.ownAttr(TEMPLATE_ATTR_FORMAT);
@@ -174,9 +179,9 @@ export const traceHelperFile = function traceHelperFile(opts?: TraceHelperOpts):
         `export async function ${fnName}(`,
         `  om: ObjectManager,`,
         `  responseMo: MetaObject,`,
-        `  input: Omit<LlmCallInput, ${sti ? `"llmRequest" | "callType"` : `"llmRequest"`}> & { llmRequest: ${requestType} },`,
+        `  input: Omit<LlmCallInput, ${recordInputOmit}> & { llmRequest: ${requestType} },`,
         `): Promise<${entityName}TraceResult> {`,
-        `  const result = await recordLlmCall(${sti ? `{ ...input, callType: ${JSON.stringify(callTypeValue)} }` : `input`}, {`,
+        `  const result = await recordLlmCall(${recordArg}, {`,
         `    recorder: new LlmCallDbRecorder(om, "${entityName}"),`,
         `    responseMo,`,
         `    format: ${formatLiteral},`,

server/typescript/packages/codegen-ts/test/ai-trace-sti.test.ts

@@ -51,10 +51,12 @@ async function genTrace(): Promise<{ classify: string; summarize: string }> {
 
 describe("ai-trace #1c — STI callType stamping", () => {
   test("record<Entity> omits callType from input and stamps the discriminator value", async () => {
-    const { classify } = await genTrace();
+    const { classify, summarize } = await genTrace();
+    // both subtypes drop callType from the caller input and stamp their own value
     expect(classify).toContain('Omit<LlmCallInput, "llmRequest" | "callType">');
-    expect(classify).toContain('callType: "classify"');
-    expect(classify).toContain("...input,");
+    expect(classify).toContain('{ ...input, callType: "classify" }');
+    expect(summarize).toContain('Omit<LlmCallInput, "llmRequest" | "callType">');
+    expect(summarize).toContain('{ ...input, callType: "summarize" }');
   });
 
   test("call<Entity> stamps the discriminator value (not the entity name)", async () => {

server/typescript/packages/codegen-ts/test/derive-trace-fields.test.ts

@@ -60,6 +60,10 @@ describe("derive trace fields", () => {
     const h = readFileSync(join(tmp, "ClassifyCall.trace.ts"), "utf-8");
     expect(h).toContain("recordClassifyCall");
     expect(h).toContain("recordLlmCall");
+    // non-STI invariant: a trace entity that is NOT a TPH subtype keeps callType
+    // caller-supplied (no "| callType" omission, no spread-injection).
+    expect(h).toContain('Omit<LlmCallInput, "llmRequest">');
+    expect(h).not.toContain('"llmRequest" | "callType"');
   });
 
   test("trace-helper emits both record and call helpers for a renderable prompt", async () => {