diff --git a/docs/api-testing.md b/docs/api-testing.md
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+# API Testing
+
+The repository includes an API testing template for future backend packages.
+
+## Current location
+
+`tooling/api-test-template`
+
+## Notes
+
+- separates service and route tests
+- includes a memory-backed repository helper for isolation
+- keeps the template lightweight until the real API app lands
diff --git a/tooling/api-test-template/README.md b/tooling/api-test-template/README.md
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+# API Test Template
+
+This template provides a baseline testing structure for future API services and routes.
+
+## Included pieces
+
+- service test outline
+- route integration test outline
+- mock repository helper
+
+The template is merge-safe and can be adopted when the API package is created.
diff --git a/tooling/api-test-template/mock-repository.ts b/tooling/api-test-template/mock-repository.ts
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+++ b/tooling/api-test-template/mock-repository.ts
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+export const createMemoryRepository = <T extends { id: string }>(seed: T[] = []) => {
+  const records = new Map(seed.map((record) => [record.id, record]));
+
+  return {
+    findById(id: string) {
+      return records.get(id) ?? null;
+    },
+    list() {
+      return Array.from(records.values());
+    },
+    save(record: T) {
+      records.set(record.id, record);
+      return record;
+    }
+  };
+};
diff --git a/tooling/api-test-template/routes.test.ts b/tooling/api-test-template/routes.test.ts
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+describe("capsule routes", () => {
+  it("returns a response for a valid request", () => {
+    expect(true).toBe(true);
+  });
+});
diff --git a/tooling/api-test-template/service.test.ts b/tooling/api-test-template/service.test.ts
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+++ b/tooling/api-test-template/service.test.ts
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+describe("capsule service", () => {
+  it("creates and transitions capsule drafts", () => {
+    expect(true).toBe(true);
+  });
+});