diff --git a/actions/setup/js/create_pr_review_comment.cjs b/actions/setup/js/create_pr_review_comment.cjs
index 41915f959e0..89aa3b25022 100644
--- a/actions/setup/js/create_pr_review_comment.cjs
+++ b/actions/setup/js/create_pr_review_comment.cjs
@@ -12,6 +12,8 @@ const { createAuthenticatedGitHubClient } = require("./handler_auth.cjs");
 const { buildWorkflowRunUrl } = require("./workflow_metadata_helpers.cjs");
 const { isTemplatableTrue, isStagedMode, logStagedPreviewInfo, checkRequiredFilter } = require("./safe_output_helpers.cjs");
 const { resolveAllowedMentionsFromPayload } = require("./resolve_mentions_from_payload.cjs");
+const { resolveInvocationContext } = require("./invocation_context_helpers.cjs");
+const { ERR_VALIDATION } = require("./error_codes.cjs");
 
 /** @type {string} Safe output type handled by this module */
 const HANDLER_TYPE = "create_pull_request_review_comment";
@@ -38,6 +40,20 @@ async function main(config = {}) {
   const legacyBuffer = registry ? null : config._prReviewBuffer || null;
   const { defaultTargetRepo, allowedRepos } = resolveTargetRepoConfig(config);
   const githubClient = await createAuthenticatedGitHubClient(config);
+  let invocationContext = {};
+  try {
+    invocationContext = resolveInvocationContext(context);
+  } catch (error) {
+    const typedError = /** @type {Error & { code?: string }} */ (error);
+    const isValidationError = typedError.code === ERR_VALIDATION;
+    if (isValidationError) {
+      throw error;
+    }
+    const errorMessage = getErrorMessage(error);
+    core.warning(`create_pull_request_review_comment: failed to resolve invocation context, using raw context: ${errorMessage}`);
+  }
+  const effectiveEventName = invocationContext.eventName || context.eventName;
+  const effectivePayload = invocationContext.eventPayload || context.payload;
   const requiredLabels = Array.isArray(config.required_labels) ? config.required_labels : [];
   const requiredTitlePrefix = config.required_title_prefix || "";
   if (requiredLabels.length > 0) core.info(`Required labels (all): ${requiredLabels.join(", ")}`);
@@ -85,9 +101,9 @@ async function main(config = {}) {
   }
 
   // Extract triggering context for footer generation
-  const triggeringIssueNumber = context.payload?.issue?.number && !context.payload?.issue?.pull_request ? context.payload.issue.number : undefined;
-  const triggeringPRNumber = context.payload?.pull_request?.number || (context.payload?.issue?.pull_request ? context.payload.issue.number : undefined);
-  const triggeringDiscussionNumber = context.payload?.discussion?.number;
+  const triggeringIssueNumber = effectivePayload?.issue?.number && !effectivePayload?.issue?.pull_request ? effectivePayload.issue.number : undefined;
+  const triggeringPRNumber = effectivePayload?.pull_request?.number || (effectivePayload?.issue?.pull_request ? effectivePayload.issue.number : undefined);
+  const triggeringDiscussionNumber = effectivePayload?.discussion?.number;
 
   const workflowName = process.env.GH_AW_WORKFLOW_NAME || "Workflow";
   const workflowSource = process.env.GH_AW_WORKFLOW_SOURCE || "";
@@ -154,11 +170,11 @@ async function main(config = {}) {
 
     // Check if we're in a pull request context, or an issue comment context on a PR
     const isPRContext =
-      context.eventName === "pull_request" ||
-      context.eventName === "pull_request_target" ||
-      context.eventName === "pull_request_review" ||
-      context.eventName === "pull_request_review_comment" ||
-      (context.eventName === "issue_comment" && context.payload.issue && context.payload.issue.pull_request);
+      effectiveEventName === "pull_request" ||
+      effectiveEventName === "pull_request_target" ||
+      effectiveEventName === "pull_request_review" ||
+      effectiveEventName === "pull_request_review_comment" ||
+      (effectiveEventName === "issue_comment" && effectivePayload.issue && effectivePayload.issue.pull_request);
 
     // Validate context based on target configuration
     if (commentTarget === "triggering" && !isPRContext) {
@@ -229,11 +245,11 @@ async function main(config = {}) {
       }
     } else {
       // Default behavior: use triggering PR
-      if (context.payload.pull_request) {
-        pullRequestNumber = context.payload.pull_request.number;
-        pullRequest = context.payload.pull_request;
-      } else if (context.payload.issue && context.payload.issue.pull_request) {
-        pullRequestNumber = context.payload.issue.number;
+      if (effectivePayload.pull_request) {
+        pullRequestNumber = effectivePayload.pull_request.number;
+        pullRequest = effectivePayload.pull_request;
+      } else if (effectivePayload.issue && effectivePayload.issue.pull_request) {
+        pullRequestNumber = effectivePayload.issue.number;
       } else {
         core.warning("Pull request context detected but no pull request found in payload");
         return {
diff --git a/actions/setup/js/create_pr_review_comment.test.cjs b/actions/setup/js/create_pr_review_comment.test.cjs
index 694cba41c66..7ef2d0a7382 100644
--- a/actions/setup/js/create_pr_review_comment.test.cjs
+++ b/actions/setup/js/create_pr_review_comment.test.cjs
@@ -463,6 +463,99 @@ describe("create_pr_review_comment.cjs", () => {
     expect(buffer.getBufferedCount()).toBe(1);
   });
 
+  it("should use the original PR context for centralized slash-command dispatches", async () => {
+    global.context = {
+      eventName: "workflow_dispatch",
+      runId: 12345,
+      repo: { owner: "testowner", repo: "testrepo" },
+      payload: {
+        inputs: {
+          event_name: "issue_comment",
+          event_payload: JSON.stringify({
+            issue: { number: 456, pull_request: {} },
+            repository: mockContext.payload.repository,
+          }),
+        },
+      },
+    };
+    mockGithub.rest.pulls.get.mockResolvedValue({
+      data: { number: 456, head: { sha: "dispatch123abc" } },
+    });
+    const handler = await createHandler({ target: "triggering" });
+    const message = {
+      type: "create_pull_request_review_comment",
+      pull_request_number: 456,
+      path: "src/main.js",
+      line: 5,
+      body: "Review comment from centralized slash command",
+    };
+
+    const result = await handler(message, {});
+
+    expect(result.success).toBe(true);
+    expect(result.buffered).toBe(true);
+    expect(result.pull_request_number).toBe(456);
+    expect(mockGithub.rest.pulls.get).toHaveBeenCalledWith({
+      owner: "testowner",
+      repo: "testrepo",
+      pull_number: 456,
+    });
+    expect(buffer.getBufferedCount()).toBe(1);
+  });
+
+  it("falls back to raw context when resolveInvocationContext returns empty object", async () => {
+    const invocationHelpersPath = path.join(__dirname, "invocation_context_helpers.cjs");
+    const invocationHelpers = require(invocationHelpersPath);
+    const resolveInvocationContextSpy = vi.spyOn(invocationHelpers, "resolveInvocationContext").mockReturnValue({});
+    try {
+      const handler = await createHandler({ target: "triggering" });
+      const message = {
+        type: "create_pull_request_review_comment",
+        path: "src/main.js",
+        line: 5,
+        body: "Review comment from fallback context",
+      };
+
+      const result = await handler(message, {});
+
+      expect(result.success).toBe(true);
+      expect(result.buffered).toBe(true);
+      expect(result.pull_request_number).toBe(123);
+      expect(buffer.getBufferedCount()).toBe(1);
+      expect(resolveInvocationContextSpy).toHaveBeenCalled();
+    } finally {
+      resolveInvocationContextSpy.mockRestore();
+    }
+  });
+
+  it("falls back to raw context when resolveInvocationContext throws a non-validation error", async () => {
+    const invocationHelpersPath = path.join(__dirname, "invocation_context_helpers.cjs");
+    const invocationHelpers = require(invocationHelpersPath);
+    const resolveInvocationContextSpy = vi.spyOn(invocationHelpers, "resolveInvocationContext").mockImplementation(() => {
+      throw new Error("boom");
+    });
+    try {
+      const handler = await createHandler({ target: "triggering" });
+      const message = {
+        type: "create_pull_request_review_comment",
+        path: "src/main.js",
+        line: 5,
+        body: "Review comment from thrown context resolver",
+      };
+
+      const result = await handler(message, {});
+
+      expect(result.success).toBe(true);
+      expect(result.buffered).toBe(true);
+      expect(result.pull_request_number).toBe(123);
+      expect(buffer.getBufferedCount()).toBe(1);
+      expect(resolveInvocationContextSpy).toHaveBeenCalled();
+      expect(mockCore.warning).toHaveBeenCalledWith(expect.stringContaining("failed to resolve invocation context"));
+    } finally {
+      resolveInvocationContextSpy.mockRestore();
+    }
+  });
+
   it("should reject comments targeting a different PR than the first comment", async () => {
     // First comment sets context to PR #123
     const handler = await createHandler();
diff --git a/actions/setup/js/invocation_context_helpers.cjs b/actions/setup/js/invocation_context_helpers.cjs
index 7c01161633f..8c4bb023343 100644
--- a/actions/setup/js/invocation_context_helpers.cjs
+++ b/actions/setup/js/invocation_context_helpers.cjs
@@ -190,7 +190,7 @@ function checkAllowedRepo(workflowRepo, targetRepo) {
 
   const validation = validateTargetRepo(targetRepoSlug, defaultRepo, allowedRepos);
   if (!validation.valid) {
-    throw new Error(`${ERR_VALIDATION}: ${validation.error}`);
+    throw Object.assign(new Error(`${ERR_VALIDATION}: ${validation.error}`), { code: ERR_VALIDATION });
   }
 }