PostHog · frankh · Jul 8, 2026 · Jul 7, 2026 · Jul 7, 2026 · Jul 7, 2026
diff --git a/packages/agent/src/agent.ts b/packages/agent/src/agent.ts
@@ -1,3 +1,4 @@
+import { buildPrOutput, mergePrUrls, readPrUrls } from "@posthog/shared";
 import {
   createAcpConnection,
   type InProcessAcpConnection,
@@ -167,8 +168,13 @@ export class Agent {
       throw error;
     }
 
+    const freshOutput = await this.posthogAPI
+      .getTaskRun(taskId, this.taskRunId)
+      .then((run) => run.output)
+      .catch(() => null);
+    const urls = mergePrUrls(readPrUrls(freshOutput), [prUrl]);
     const updates: TaskRunUpdate = {
-      output: { pr_url: prUrl },
+      output: buildPrOutput(freshOutput, urls),
     };
     if (branchName) {
       updates.branch = branchName;

diff --git a/packages/agent/src/pr-url-detector.test.ts b/packages/agent/src/pr-url-detector.test.ts
@@ -1,5 +1,10 @@
 import { describe, expect, it } from "vitest";
-import { findPrUrl, wasCreatedRecently } from "./pr-url-detector";
+import {
+  findPrUrl,
+  findPrUrls,
+  wasCreatedByLogin,
+  wasCreatedRecently,
+} from "./pr-url-detector";
 
 const PR_URL = "https://github.com/PostHog/posthog.com/pull/17764";
 
@@ -33,6 +38,38 @@ describe("findPrUrl", () => {
   });
 });
 
+describe("findPrUrls", () => {
+  const OTHER = "https://github.com/PostHog/posthog/pull/99";
+
+  it("finds every PR URL in one chunk, in order", () => {
+    expect(findPrUrls(`Opened ${PR_URL} and ${OTHER} today`)).toEqual([
+      PR_URL,
+      OTHER,
+    ]);
+  });
+
+  it("dedupes repeated mentions of the same PR", () => {
+    expect(findPrUrls(`${PR_URL} again: ${PR_URL}`)).toEqual([PR_URL]);
+  });
+
+  it("returns an empty array when there is no PR URL", () => {
+    expect(findPrUrls("nothing here")).toEqual([]);
+  });
+});
+
+describe("wasCreatedByLogin", () => {
+  it.each([
+    ["run-owner", "run-owner", true],
+    ["Run-Owner", "run-owner", true],
+    ["someone-else", "run-owner", false],
+    [null, "run-owner", false],
+    ["run-owner", null, false],
+    ["", "", false],
+  ] as const)("author=%s login=%s -> %s", (author, login, expected) => {
+    expect(wasCreatedByLogin(author, login)).toBe(expected);
+  });
+});
+
 describe("wasCreatedRecently", () => {
   const now = new Date("2026-06-18T17:00:00Z").getTime();
   const maxAge = 15 * 60 * 1000;

diff --git a/packages/agent/src/pr-url-detector.ts b/packages/agent/src/pr-url-detector.ts
@@ -1,11 +1,24 @@
-const PR_URL_REGEX = /https:\/\/github\.com\/[^/\s"]+\/[^/\s"]+\/pull\/\d+/;
+const PR_URL_REGEX = /https:\/\/github\.com\/[^/\s"]+\/[^/\s"]+\/pull\/\d+/g;
 
 // A fixed window (not "since run start") so a PR the agent merely views on a
 // long run is too old to be mistaken for one it just created.
 export const PR_CREATION_RECENCY_MS = 5 * 60 * 1000;
 
 export function findPrUrl(text: string): string | null {
-  return text.match(PR_URL_REGEX)?.[0] ?? null;
+  return findPrUrls(text)[0] ?? null;
+}
+
+export function findPrUrls(text: string): string[] {
+  return [...new Set(text.match(PR_URL_REGEX) ?? [])];
+}
+
+// Fails closed on missing/invalid input so we never attribute on uncertainty.
+export function wasCreatedByLogin(
+  author: string | null | undefined,
+  login: string | null | undefined,
+): boolean {
+  if (!author || !login) return false;
+  return author.toLowerCase() === login.toLowerCase();
 }
 
 // Fails closed on missing/invalid input so we never attribute on uncertainty.

diff --git a/packages/agent/src/server/agent-server.test.ts b/packages/agent/src/server/agent-server.test.ts
@@ -1864,18 +1864,45 @@ describe("AgentServer HTTP Mode", () => {
         p: JwtPayload,
         u: Record<string, unknown> | undefined,
       ): void;
-      fetchPrCreatedAt(url: string): Promise<string | null>;
+      fetchPrAttribution(
+        url: string,
+      ): Promise<{ createdAt: string | null; author: string | null }>;
+      fetchGhLogin(): Promise<string | null>;
       detectedPrUrl: string | null;
-      posthogAPI: { updateTaskRun: ReturnType<typeof vi.fn> };
+      posthogAPI: {
+        getTaskRun: ReturnType<typeof vi.fn>;
+        updateTaskRun: ReturnType<typeof vi.fn>;
+      };
     };
 
     const justNow = () => new Date().toISOString();
     const longAgo = "2020-01-01T00:00:00Z";
+    const GH_LOGIN = "run-owner";
 
-    const setup = (prCreatedAt: string | null): PrTestServer => {
+    const setup = (
+      prCreatedAt: string | null,
+      prAuthor: string | null = GH_LOGIN,
+    ): PrTestServer => {
       const s = createServer() as unknown as PrTestServer;
-      s.fetchPrCreatedAt = vi.fn(async () => prCreatedAt);
-      s.posthogAPI = { updateTaskRun: vi.fn(async () => ({})) };
+      s.fetchPrAttribution = vi.fn(async () => ({
+        createdAt: prCreatedAt,
+        author: prAuthor,
+      }));
+      s.fetchGhLogin = vi.fn(async () => GH_LOGIN);
+      let storedOutput: Record<string, unknown> | null = null;
+      s.posthogAPI = {
+        getTaskRun: vi.fn(async () => ({ output: storedOutput })),
+        updateTaskRun: vi.fn(
+          async (
+            _taskId: string,
+            _runId: string,
+            updates: { output: Record<string, unknown> },
+          ) => {
+            storedOutput = updates.output;
+            return {};
+          },
+        ),
+      };
       return s;
     };
 
@@ -1886,7 +1913,7 @@ describe("AgentServer HTTP Mode", () => {
       s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
       await flush();
       expect(s.posthogAPI.updateTaskRun).toHaveBeenCalledWith("t", "r", {
-        output: { pr_url: PR_URL },
+        output: { pr_url: PR_URL, pr_urls: [PR_URL] },
       });
       expect(s.detectedPrUrl).toBe(PR_URL);
     });
@@ -1903,7 +1930,7 @@ describe("AgentServer HTTP Mode", () => {
       const s = setup(justNow());
       s.maybeAttachCreatedPr(payload, { sessionUpdate: "agent_thought_chunk" });
       await flush();
-      expect(s.fetchPrCreatedAt).not.toHaveBeenCalled();
+      expect(s.fetchPrAttribution).not.toHaveBeenCalled();
       expect(s.posthogAPI.updateTaskRun).not.toHaveBeenCalled();
     });
 
@@ -1913,20 +1940,19 @@ describe("AgentServer HTTP Mode", () => {
       s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
       s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
       await flush();
-      expect(s.fetchPrCreatedAt).toHaveBeenCalledTimes(1);
+      expect(s.fetchPrAttribution).toHaveBeenCalledTimes(1);
       expect(s.posthogAPI.updateTaskRun).toHaveBeenCalledTimes(1);
     });
 
-    it("attributes the most recent PR when a run opens several, in detection order", async () => {
-      // output.pr_url holds one value; the latest PR the run created is the useful one.
+    it("accumulates every PR a run opens, keeping the first as primary", async () => {
       const s = setup(justNow());
       const second = "https://github.com/PostHog/posthog.com/pull/17765";
       s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
       s.maybeAttachCreatedPr(payload, terminalUpdate(second));
       await flush();
       expect(s.posthogAPI.updateTaskRun).toHaveBeenCalledTimes(2);
       expect(s.posthogAPI.updateTaskRun).toHaveBeenLastCalledWith("t", "r", {
-        output: { pr_url: second },
+        output: { pr_url: PR_URL, pr_urls: [PR_URL, second] },
       });
       expect(s.detectedPrUrl).toBe(second);
     });
@@ -1935,15 +1961,32 @@ describe("AgentServer HTTP Mode", () => {
       const viewed = "https://github.com/PostHog/posthog.com/pull/1";
       // The created PR reads as recent; the later, merely-viewed PR reads as old.
       const s = setup(justNow());
-      s.fetchPrCreatedAt = vi.fn(async (url: string) =>
-        url === PR_URL ? justNow() : longAgo,
-      );
+      s.fetchPrAttribution = vi.fn(async (url: string) => ({
+        createdAt: url === PR_URL ? justNow() : longAgo,
+        author: GH_LOGIN,
+      }));
       s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
       s.maybeAttachCreatedPr(payload, terminalUpdate(viewed));
       await flush();
       expect(s.detectedPrUrl).toBe(PR_URL);
       expect(s.posthogAPI.updateTaskRun).toHaveBeenCalledTimes(1);
     });
+
+    it("does not attribute a fresh PR authored by someone else (merely viewed)", async () => {
+      const s = setup(justNow(), "someone-else");
+      s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
+      await flush();
+      expect(s.posthogAPI.updateTaskRun).not.toHaveBeenCalled();
+      expect(s.detectedPrUrl).toBeNull();
+    });
+
+    it("fails closed when the run's GitHub identity cannot be resolved", async () => {
+      const s = setup(justNow());
+      s.fetchGhLogin = vi.fn(async () => null);
+      s.maybeAttachCreatedPr(payload, terminalUpdate(PR_URL));
+      await flush();
+      expect(s.posthogAPI.updateTaskRun).not.toHaveBeenCalled();
+    });
   });
 
   describe("buildCloudSystemPrompt", () => {

diff --git a/packages/agent/src/server/agent-server.ts b/packages/agent/src/server/agent-server.ts
@@ -16,7 +16,12 @@ import {
 import { type ServerType, serve } from "@hono/node-server";
 import { execGh } from "@posthog/git/gh";
 import { getCurrentBranch } from "@posthog/git/queries";
-import type { Adapter } from "@posthog/shared";
+import {
+  type Adapter,
+  buildPrOutput,
+  mergePrUrls,
+  readPrUrls,
+} from "@posthog/shared";
 import { unzipSync } from "fflate";
 import { Hono } from "hono";
 import { z } from "zod";
@@ -45,7 +50,11 @@ import type { PermissionMode } from "../execution-mode";
 import { DEFAULT_CODEX_MODEL, fetchGatewayModels } from "../gateway-models";
 import { HandoffCheckpointTracker } from "../handoff-checkpoint";
 import { PostHogAPIClient } from "../posthog-api";
-import { findPrUrl, wasCreatedRecently } from "../pr-url-detector";
+import {
+  findPrUrls,
+  wasCreatedByLogin,
+  wasCreatedRecently,
+} from "../pr-url-detector";
 import {
   formatConversationForResume,
   type ResumeState,
@@ -3355,13 +3364,14 @@ ${signedCommitInstructions}${prLinkInstructions}${shellEfficiencyInstructions}
     update: Record<string, unknown> | undefined,
   ): void {
     if (!update) return;
-    const prUrl = findPrUrl(JSON.stringify(update));
-    if (!prUrl || this.evaluatedPrUrls.has(prUrl)) return;
-    this.evaluatedPrUrls.add(prUrl);
-    // Chain so attributions run in detection order; later PRs overwrite earlier ones.
-    this.prAttributionChain = this.prAttributionChain
-      .catch(() => {})
-      .then(() => this.attachPrIfCreatedThisRun(payload, prUrl));
+    for (const prUrl of findPrUrls(JSON.stringify(update))) {
+      if (this.evaluatedPrUrls.has(prUrl)) continue;
+      this.evaluatedPrUrls.add(prUrl);
+      // Chain so attributions run in detection order; later PRs append after earlier ones.
+      this.prAttributionChain = this.prAttributionChain
+        .catch(() => {})
+        .then(() => this.attachPrIfCreatedThisRun(payload, prUrl));
+    }
   }
 
   private async attachPrIfCreatedThisRun(
@@ -3371,9 +3381,13 @@ ${signedCommitInstructions}${prLinkInstructions}${shellEfficiencyInstructions}
     // Already the attributed PR (e.g. seeded from a Slack notification, or re-detected).
     if (prUrl === this.detectedPrUrl) return;
 
-    let createdAt: string | null;
+    let attribution: { createdAt: string | null; author: string | null };
+    let ghLogin: string | null;
     try {
-      createdAt = await this.fetchPrCreatedAt(prUrl);
+      [attribution, ghLogin] = await Promise.all([
+        this.fetchPrAttribution(prUrl),
+        this.fetchGhLogin(),
+      ]);
     } catch (err) {
       this.logger.debug("PR attribution lookup failed", {
         runId: payload.run_id,
@@ -3383,14 +3397,21 @@ ${signedCommitInstructions}${prLinkInstructions}${shellEfficiencyInstructions}
       return;
     }
 
-    // Only attribute PRs created during this run, not ones the agent merely viewed.
-    if (!wasCreatedRecently(createdAt, Date.now())) return;
+    // Only attribute PRs created during this run by this run's own GitHub
+    // identity — not ones the agent merely viewed.
+    if (!wasCreatedRecently(attribution.createdAt, Date.now())) return;
+    if (!wasCreatedByLogin(attribution.author, ghLogin)) return;
 
     this.detectedPrUrl = prUrl;
 
     try {
+      const freshOutput = await this.posthogAPI
+        .getTaskRun(payload.task_id, payload.run_id)
+        .then((run) => run.output)
+        .catch(() => null);
+      const urls = mergePrUrls(readPrUrls(freshOutput), [prUrl]);
       await this.posthogAPI.updateTaskRun(payload.task_id, payload.run_id, {
-        output: { pr_url: prUrl },
+        output: buildPrOutput(freshOutput, urls),
       });
       this.logger.debug("Attributed created PR to task run", {
         taskId: payload.task_id,
@@ -3407,21 +3428,50 @@ ${signedCommitInstructions}${prLinkInstructions}${shellEfficiencyInstructions}
     }
   }
 
-  private async fetchPrCreatedAt(prUrl: string): Promise<string | null> {
-    const res = await execGh(["pr", "view", prUrl, "--json", "createdAt"], {
-      cwd: this.config.repositoryPath,
-      timeoutMs: 10_000,
-    });
-    if (res.exitCode !== 0) return null;
+  private async fetchPrAttribution(
+    prUrl: string,
+  ): Promise<{ createdAt: string | null; author: string | null }> {
+    const res = await execGh(
+      ["pr", "view", prUrl, "--json", "createdAt,author"],
+      {
+        cwd: this.config.repositoryPath,
+        timeoutMs: 10_000,
+      },
+    );
+    if (res.exitCode !== 0) return { createdAt: null, author: null };
     try {
-      return (
-        (JSON.parse(res.stdout) as { createdAt?: string }).createdAt ?? null
-      );
+      const data = JSON.parse(res.stdout) as {
+        createdAt?: string;
+        author?: { login?: string };
+      };
+      return {
+        createdAt: data.createdAt ?? null,
+        author: data.author?.login ?? null,
+      };
     } catch {
-      return null;
+      return { createdAt: null, author: null };
     }
   }
 
+  private ghLoginPromise: Promise<string | null> | null = null;
+
+  private fetchGhLogin(): Promise<string | null> {
+    this.ghLoginPromise ??= execGh(["api", "user", "--jq", ".login"], {
+      cwd: this.config.repositoryPath,
+      timeoutMs: 10_000,
+    })
+      .then((res) => {
+        const login = res.exitCode === 0 ? res.stdout.trim() : "";
+        if (!login) this.ghLoginPromise = null;
+        return login || null;
+      })
+      .catch(() => {
+        this.ghLoginPromise = null;
+        return null;
+      });
+    return this.ghLoginPromise;
+  }
+
   private async cleanupSession({
     completeEventStream = false,
   }: {

diff --git a/packages/core/src/git-interaction/gitInteractionService.test.ts b/packages/core/src/git-interaction/gitInteractionService.test.ts
@@ -276,6 +276,7 @@ describe("GitInteractionService.runCreatePr", () => {
     expect(effects.attachPrUrlToTask).toHaveBeenCalledWith(
       "t",
       "https://example.test/pr/1",
+      undefined,
     );
     if (result.outcome === "success") {
       expect(result.linkedBranchName).toBe("feature-x");