diff --git a/actions/setup/js/close_entity_helpers.test.cjs b/actions/setup/js/close_entity_helpers.test.cjs
index f97439fdeb4..38b275acce4 100644
--- a/actions/setup/js/close_entity_helpers.test.cjs
+++ b/actions/setup/js/close_entity_helpers.test.cjs
@@ -1,6 +1,7 @@
 import { describe, it, expect, beforeEach, vi } from "vitest";
 import fs from "fs";
 import path from "path";
+import { fileURLToPath } from "url";
 const mockCore = { debug: vi.fn(), info: vi.fn(), warning: vi.fn(), error: vi.fn(), setFailed: vi.fn(), setOutput: vi.fn(), summary: { addRaw: vi.fn().mockReturnThis(), write: vi.fn().mockResolvedValue() } },
   mockContext = { eventName: "issues", runId: 12345, repo: { owner: "testowner", repo: "testrepo" }, payload: { issue: { number: 42 }, pull_request: { number: 100 }, repository: { html_url: "https://github.com/testowner/testrepo" } } };
 ((global.core = mockCore), (global.context = mockContext));
@@ -14,6 +15,10 @@ describe("close_entity_helpers", () => {
       delete process.env.GH_AW_CLOSE_PR_REQUIRED_LABELS,
       delete process.env.GH_AW_CLOSE_PR_REQUIRED_TITLE_PREFIX,
       delete process.env.GH_AW_CLOSE_PR_TARGET,
+      // Point GH_AW_PROMPTS_DIR to the source md/ directory so getPromptPath()
+      // resolves template files from the source tree in test environments where
+      // RUNNER_TEMP is set but the runtime prompts directory is not populated.
+      (process.env.GH_AW_PROMPTS_DIR = path.join(path.dirname(fileURLToPath(import.meta.url)), "../md")),
       (global.context.eventName = "issues"),
       (global.context.payload.issue = { number: 42 }),
       (global.context.payload.pull_request = { number: 100 }));
diff --git a/actions/setup/js/messages.test.cjs b/actions/setup/js/messages.test.cjs
index 40e13e77e7f..5e096f9ce88 100644
--- a/actions/setup/js/messages.test.cjs
+++ b/actions/setup/js/messages.test.cjs
@@ -10,6 +10,8 @@
  * - Run status messages (started, success, failure)
  */
 import { describe, it, expect, beforeEach, vi } from "vitest";
+import path from "path";
+import { fileURLToPath } from "url";
 
 // Mock core for GitHub Actions environment
 const mockCore = {
@@ -36,6 +38,10 @@ describe("messages.cjs", () => {
     delete process.env.GH_AW_EFFECTIVE_TOKENS;
     delete process.env.GH_AW_DETECTION_CONCLUSION;
     delete process.env.GH_AW_DETECTION_REASON;
+    // Point GH_AW_PROMPTS_DIR to the source md/ directory so getPromptPath()
+    // resolves template files from the source tree in test environments where
+    // RUNNER_TEMP is set but the runtime prompts directory is not populated.
+    process.env.GH_AW_PROMPTS_DIR = path.join(path.dirname(fileURLToPath(import.meta.url)), "../md");
     // Clear cache by reimporting
     vi.resetModules();
   });
diff --git a/actions/setup/js/messages_footer.cjs b/actions/setup/js/messages_footer.cjs
index 08a23cf1887..92a58e31bbb 100644
--- a/actions/setup/js/messages_footer.cjs
+++ b/actions/setup/js/messages_footer.cjs
@@ -8,8 +8,7 @@
  * for safe-output workflows.
  */
 
-const path = require("path");
-const { getMessages, renderTemplate, renderTemplateFromFile, toSnakeCase } = require("./messages_core.cjs");
+const { getMessages, renderTemplate, renderTemplateFromFile, toSnakeCase, getPromptPath } = require("./messages_core.cjs");
 const { getMissingInfoSections } = require("./missing_messages_helper.cjs");
 const { getBlockedDomains, generateBlockedDomainsSection } = require("./firewall_blocked_domains.cjs");
 const { getDifcFilteredEvents, generateDifcFilteredSection } = require("./gateway_difc_filtered.cjs");
@@ -132,7 +131,7 @@ function getFooterInstallMessage(ctx) {
   // Create context with both camelCase and snake_case keys, including computed agentic_workflow_url
   const templateContext = toSnakeCase({ ...ctx, agenticWorkflowUrl });
 
-  const defaultInstallTemplatePath = path.join(__dirname, "../md/workflow_install_note.md");
+  const defaultInstallTemplatePath = getPromptPath("workflow_install_note.md");
 
   // Use custom installation message if configured
   return messages?.footerInstall ? renderTemplate(messages.footerInstall, templateContext) : renderTemplateFromFile(defaultInstallTemplatePath, templateContext);
diff --git a/actions/setup/js/pr_review_buffer.test.cjs b/actions/setup/js/pr_review_buffer.test.cjs
index a6a21e2ee23..d4630a816f3 100644
--- a/actions/setup/js/pr_review_buffer.test.cjs
+++ b/actions/setup/js/pr_review_buffer.test.cjs
@@ -1,4 +1,6 @@
 import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
+import path from "path";
+import { fileURLToPath } from "url";
 
 const mockCore = {
   debug: vi.fn(),
@@ -28,6 +30,7 @@ const { createReviewBuffer } = require("./pr_review_buffer.cjs");
 describe("pr_review_buffer (factory pattern)", () => {
   let buffer;
   let originalMessages;
+  let originalPromptsDir;
 
   beforeEach(() => {
     vi.clearAllMocks();
@@ -36,6 +39,12 @@ describe("pr_review_buffer (factory pattern)", () => {
     originalMessages = process.env.GH_AW_SAFE_OUTPUT_MESSAGES;
     delete process.env.GH_AW_SAFE_OUTPUT_MESSAGES;
 
+    // Point GH_AW_PROMPTS_DIR to the source md/ directory so getPromptPath()
+    // resolves template files from the source tree in test environments where
+    // RUNNER_TEMP is set but the runtime prompts directory is not populated.
+    originalPromptsDir = process.env.GH_AW_PROMPTS_DIR;
+    process.env.GH_AW_PROMPTS_DIR = path.join(path.dirname(fileURLToPath(import.meta.url)), "../md");
+
     // Default: return empty file list so path filtering is skipped unless explicitly mocked
     mockGithub.rest.pulls.listFiles.mockResolvedValue({ data: [] });
 
@@ -50,6 +59,11 @@ describe("pr_review_buffer (factory pattern)", () => {
     } else {
       delete process.env.GH_AW_SAFE_OUTPUT_MESSAGES;
     }
+    if (originalPromptsDir !== undefined) {
+      process.env.GH_AW_PROMPTS_DIR = originalPromptsDir;
+    } else {
+      delete process.env.GH_AW_PROMPTS_DIR;
+    }
   });
 
   it("should create independent buffer instances", () => {