chore(event formatter): add new event formatter to mcp

packages/mcp-core/src/api-client/client.ts

@@ -3218,7 +3218,7 @@ export class SentryApiService {
     opts?: RequestOptions,
   ): Promise<Event> {
     const body = await this.requestJSON(
-      `/organizations/${organizationSlug}/issues/${issueId}/events/${eventId}/`,
+      `/organizations/${organizationSlug}/issues/${issueId}/events/${eventId}/?llmFormat=markdown`,
       undefined,
       opts,
     );
@@ -3983,7 +3983,7 @@ export class SentryApiService {
     opts?: RequestOptions,
   ): Promise<AutofixRunState> {
     const body = await this.requestJSON(
-      `/organizations/${organizationSlug}/issues/${issueId}/autofix/`,
+      `/organizations/${organizationSlug}/issues/${issueId}/autofix/?llmFormat=markdown`,
       undefined,
       opts,
     );

packages/mcp-core/src/api-client/schema.ts

@@ -1011,6 +1011,8 @@ const BaseEventSchema = z.object({
   _meta: z.unknown().optional(),
   // dateReceived is when the server received the event (may not be present in all contexts)
   dateReceived: z.string().datetime().optional(),
+  // shared-formatter output, present when the event endpoint is called with ?llmFormat
+  formatted: z.object({ format: z.string(), content: z.string() }).optional(),
 });
 
 export const ErrorEventSchema = BaseEventSchema.omit({
@@ -1231,6 +1233,8 @@ export const AutofixRunStateSchema = z.object({
     })
     .passthrough()
     .nullable(),
+  // shared-formatter output, present when the autofix endpoint is called with ?llmFormat
+  formatted: z.object({ format: z.string(), content: z.string() }).optional(),
 });
 
 export const EventAttachmentSchema = z.object({

packages/mcp-core/src/internal/formatting.ts

@@ -33,6 +33,7 @@ import {
   getAutofixArtifactSummaries,
   getStatusDisplayName,
   isTerminalStatus,
+  wrapSeerContent,
 } from "./tool-helpers/seer";
 import { formatToolCallInstruction } from "./tool-helpers/tool-call-formatting";
 import {
@@ -1926,6 +1927,16 @@ function formatSeerSummary(autofixState: AutofixRunState | undefined): string {
     return "";
   }
 
+  // Prefer the shared formatter's analysis when the endpoint provides it.
+  // Seer content is LLM-generated, so wrap it in the untrusted-data boundary.
+  if (autofixState.formatted?.content) {
+    const wrapped = wrapSeerContent(
+      autofixState.formatted.content,
+      autofixState.autofix.run_id,
+    );
+    return `## Seer Analysis\n\n${wrapped}\n`;
+  }
+
   const { autofix } = autofixState;
   const parts: string[] = [];
 
@@ -2128,12 +2139,12 @@ export function formatIssueOutput({
   // "default" type represents error events without exception data
   // "generic" type represents performance regressions and metric-based issues
   // "csp" type represents Content Security Policy violations
-  if (
+  const isSharedFormatterType =
     event.type === "error" ||
     event.type === "default" ||
     event.type === "generic" ||
-    event.type === "csp"
-  ) {
+    event.type === "csp";
+  if (isSharedFormatterType) {
     const typedEvent = event as
       | z.infer<typeof ErrorEventSchema>
       | z.infer<typeof DefaultEventSchema>
@@ -2147,17 +2158,34 @@ export function formatIssueOutput({
     output += `**Message**:\n${event.message}\n`;
   }
   output += "\n";
-  output += formatEventOutput(event, {
-    performanceTrace,
-    replaySummary: {
+  if (isSharedFormatterType && event.formatted?.content) {
+    // the shared formatter body doesn't include the replay note — add it here to match formatEventOutput
+    output += formatIssueReplayOutput({
       apiService,
       organizationSlug,
+      event,
       relatedReplayIds,
       experimentalMode: experimentalMode ?? false,
       availableToolNames,
       directToolNames,
-    },
-  });
+    });
+    const formattedContent = event.formatted.content;
+    output += formattedContent.endsWith("\n")
+      ? formattedContent
+      : `${formattedContent}\n`;
+  } else {
+    output += formatEventOutput(event, {
+      performanceTrace,
+      replaySummary: {
+        apiService,
+        organizationSlug,
+        relatedReplayIds,
+        experimentalMode: experimentalMode ?? false,
+        availableToolNames,
+        directToolNames,
+      },
+    });
+  }
 
   // Add Seer context if available
   if (autofixState) {

packages/mcp-core/src/internal/tool-helpers/seer.ts

@@ -116,6 +116,20 @@ function wrapSeerAnalysisOutput({
   return `<seer_analysis ${attrs.join(" ")}>\n${output.trimEnd()}\n</seer_analysis>\n`;
 }
 
+/**
+ * Wraps shared-formatter Seer analysis content in the provenance boundary,
+ * mirroring the tags getOutputForAutofixRun applies to MCP-rendered output.
+ * Seer content is LLM-generated, so it must be marked as untrusted data.
+ */
+export function wrapSeerContent(content: string, runId?: number): string {
+  return wrapSeerAnalysisOutput({
+    output: content,
+    runId,
+    step: "analysis",
+    includeProvenanceTags: true,
+  });
+}
+
 // Artifact data shapes from getsentry/sentry's
 // `src/sentry/seer/autofix/artifact_schemas.py`. Fields are LLM-generated, so
 // everything is treated as optional.

packages/mcp-core/src/tools/catalog/analyze-issue-with-seer.test.ts

@@ -57,6 +57,42 @@ describe("analyze_issue_with_seer", () => {
     expect(result).toContain("The analysis has completed successfully.");
   });
 
+  it("uses formatted.content from the autofix endpoint when present", async () => {
+    mswServer.use(
+      http.get(
+        "https://sentry.io/api/0/organizations/sentry-mcp-evals/issues/CLOUDFLARE-MCP-FMT/autofix/",
+        () =>
+          HttpResponse.json({
+            autofix: { run_id: 42, status: "completed", blocks: [] },
+            formatted: {
+              format: "markdown",
+              content: "## Root Cause\n\nSHARED-AUTOFIX-MARKER",
+            },
+          }),
+      ),
+    );
+
+    const result = await analyzeIssueWithSeer.handler(
+      {
+        organizationSlug: "sentry-mcp-evals",
+        regionUrl: null,
+        instruction: undefined,
+        issueId: "CLOUDFLARE-MCP-FMT",
+        issueUrl: undefined,
+      },
+      {
+        constraints: { organizationSlug: undefined },
+        accessToken: "access-token",
+        userId: "1",
+      },
+    );
+
+    expect(result).toContain("SHARED-AUTOFIX-MARKER"); // body from the shared /autofix/ formatter
+    // LLM-generated content is still wrapped in the untrusted-data boundary
+    expect(result).toContain('<seer_analysis run_id="42" step="analysis">');
+    expect(result).toContain("</seer_analysis>");
+  });
+
   it("wraps completed Seer-authored sections with provenance tags", async () => {
     mswServer.use(
       http.get(

packages/mcp-core/src/tools/catalog/analyze-issue-with-seer.ts

@@ -11,6 +11,7 @@ import {
   isTerminalStatus,
   getHumanInterventionGuidance,
   getOutputForAutofixRun,
+  wrapSeerContent,
   getActiveAutofixTodo,
   getSeerUnsupportedIssueMessage,
   isSeerSupportedIssue,
@@ -177,7 +178,12 @@ export default defineTool({
       if (isTerminalStatus(existingStatus)) {
         // Return results immediately, no polling needed
         output += `## Analysis ${getStatusDisplayName(existingStatus)}\n\n`;
-        output += getOutputForAutofixRun(autofixState.autofix);
+        output += autofixState.formatted?.content
+          ? wrapSeerContent(
+              autofixState.formatted.content,
+              autofixState.autofix.run_id,
+            )
+          : getOutputForAutofixRun(autofixState.autofix);
 
         if (existingStatus !== "completed") {
           output += `\n**Status**: ${existingStatus}\n`;
@@ -210,7 +216,12 @@ export default defineTool({
       // Check if completed (terminal state)
       if (isTerminalStatus(status)) {
         output += `## Analysis ${getStatusDisplayName(status)}\n\n`;
-        output += getOutputForAutofixRun(autofixState.autofix);
+        output += autofixState.formatted?.content
+          ? wrapSeerContent(
+              autofixState.formatted.content,
+              autofixState.autofix.run_id,
+            )
+          : getOutputForAutofixRun(autofixState.autofix);
 
         if (status !== "completed") {
           output += `\n**Status**: ${status}\n`;
@@ -279,7 +290,12 @@ export default defineTool({
     // Show current progress
     if (autofixState.autofix) {
       output += `**Current Status**: ${getStatusDisplayName(autofixState.autofix.status)}\n\n`;
-      output += getOutputForAutofixRun(autofixState.autofix);
+      output += autofixState.formatted?.content
+        ? wrapSeerContent(
+            autofixState.formatted.content,
+            autofixState.autofix.run_id,
+          )
+        : getOutputForAutofixRun(autofixState.autofix);
     }
 
     // Timeout reached