diff --git a/src/upload-lib.test.ts b/src/upload-lib.test.ts
index 5accb871a..5b6c0db5f 100644
--- a/src/upload-lib.test.ts
+++ b/src/upload-lib.test.ts
@@ -12,6 +12,7 @@ import * as api from "./api-client";
 import { getRunnerLogger, Logger } from "./logging";
 import { setupTests } from "./testing-utils";
 import * as uploadLib from "./upload-lib";
+import { UploadPayload } from "./upload-lib/types";
 import { GitHubVariant, initializeEnvironment, withTmpDir } from "./util";
 
 setupTests(test);
@@ -909,7 +910,15 @@ function createMockSarif(id?: string, tool?: string) {
 
 function uploadPayloadFixtures(analysis: analyses.AnalysisConfig) {
   const mockData = {
-    payload: { sarif: "base64data", commit_sha: "abc123" },
+    payload: {
+      commit_oid: "abc123",
+      ref: "ref",
+      sarif: "base64data",
+      workflow_run_id: 1,
+      workflow_run_attempt: 1,
+      checkout_uri: "uri",
+      tool_names: ["codeql"],
+    } satisfies UploadPayload,
     owner: "test-owner",
     repo: "test-repo",
     response: {
diff --git a/src/upload-lib.ts b/src/upload-lib.ts
index ac0274520..85208b7b4 100644
--- a/src/upload-lib.ts
+++ b/src/upload-lib.ts
@@ -21,6 +21,7 @@ import * as gitUtils from "./git-utils";
 import { initCodeQL } from "./init";
 import { Logger } from "./logging";
 import { getRepositoryNwo, RepositoryNwo } from "./repository";
+import { UploadPayload } from "./upload-lib/types";
 import * as util from "./util";
 import {
   ConfigurationError,
@@ -326,7 +327,7 @@ function getAutomationID(
  * This is exported for testing purposes only.
  */
 export async function uploadPayload(
-  payload: any,
+  payload: UploadPayload,
   repositoryNwo: RepositoryNwo,
   logger: Logger,
   analysis: analyses.AnalysisConfig,
@@ -618,8 +619,8 @@ export function buildPayload(
   environment: string | undefined,
   toolNames: string[],
   mergeBaseCommitOid: string | undefined,
-) {
-  const payloadObj = {
+): UploadPayload {
+  const payloadObj: UploadPayload = {
     commit_oid: commitOid,
     ref,
     analysis_key: analysisKey,
diff --git a/src/upload-lib/types.ts b/src/upload-lib/types.ts
new file mode 100644
index 000000000..b86107557
--- /dev/null
+++ b/src/upload-lib/types.ts
@@ -0,0 +1,15 @@
+export interface UploadPayload {
+  commit_oid: string;
+  ref: string;
+  analysis_key?: string;
+  analysis_name?: string;
+  sarif: string;
+  workflow_run_id: number;
+  workflow_run_attempt: number;
+  checkout_uri: string;
+  environment?: string;
+  started_at?: string;
+  tool_names: string[];
+  base_ref?: string;
+  base_sha?: string;
+}