docs: add push event documentation and tests

Address code review feedback:
- Add push event to supported events list in docs/custom-automations.md
- Add auto-rebase example workflow using push events
- Add tests for isPushEvent type guard
- Add tests for push event mode detection
- Add test to verify track_progress throws error for push events

🤖 Generated with [Claude Code](https://claude.ai/code)

docs/custom-automations.md

@@ -21,6 +21,7 @@ This action supports the following GitHub events ([learn more GitHub event trigg
 - `issues` - When issues are opened or assigned
 - `pull_request_review` - When PR reviews are submitted
 - `pull_request_review_comment` - When comments are made on PR reviews
+- `push` - When commits are pushed to a branch
 - `repository_dispatch` - Custom events triggered via API
 - `workflow_dispatch` - Manual workflow triggers (coming soon)
 
@@ -120,3 +121,42 @@ For more control over Claude's behavior, use the `claude_args` input to pass CLI
 ```
 
 This provides full access to Claude Code CLI capabilities while maintaining the simplified action interface.
+
+## Auto-Rebase PRs on Push
+
+Automatically keep PRs up to date when the main branch is updated:
+
+```yaml
+name: Auto-Rebase PRs
+
+on:
+  push:
+    branches: [main]
+
+permissions:
+  contents: write
+  pull-requests: write
+  id-token: write
+
+jobs:
+  rebase-prs:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - uses: anthropics/claude-code-action@v1
+        with:
+          prompt: |
+            Find all open PRs that are behind main and merge main into them.
+            For each PR:
+            1. Check out the PR branch
+            2. Merge main into the branch
+            3. Push the updated branch
+
+            Skip any PRs with merge conflicts - just report them.
+          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
+```
+
+This workflow triggers whenever commits are pushed to main and uses Claude to automatically merge main into any stale PR branches, keeping them up to date.

src/github/context.ts

@@ -6,6 +6,7 @@ import type {
   PullRequestEvent,
   PullRequestReviewEvent,
   PullRequestReviewCommentEvent,
+  PushEvent,
   WorkflowRunEvent,
 } from "@octokit/webhooks-types";
 import { CLAUDE_APP_BOT_ID, CLAUDE_BOT_LOGIN } from "./constants";
@@ -65,6 +66,7 @@ const AUTOMATION_EVENT_NAMES = [
   "repository_dispatch",
   "schedule",
   "workflow_run",
+  "push",
 ] as const;
 
 // Derive types from constants for better maintainability
@@ -112,14 +114,15 @@ export type ParsedGitHubContext = BaseContext & {
   isPR: boolean;
 };
 
-// Context for automation events (workflow_dispatch, repository_dispatch, schedule, workflow_run)
+// Context for automation events (workflow_dispatch, repository_dispatch, schedule, workflow_run, push)
 export type AutomationContext = BaseContext & {
   eventName: AutomationEventName;
   payload:
     | WorkflowDispatchEvent
     | RepositoryDispatchEvent
     | ScheduleEvent
-    | WorkflowRunEvent;
+    | WorkflowRunEvent
+    | PushEvent;
 };
 
 // Union type for all contexts
@@ -235,6 +238,13 @@ export function parseGitHubContext(): GitHubContext {
         payload: context.payload as unknown as WorkflowRunEvent,
       };
     }
+    case "push": {
+      return {
+        ...commonFields,
+        eventName: "push",
+        payload: context.payload as unknown as PushEvent,
+      };
+    }
     default:
       throw new Error(`Unsupported event type: ${context.eventName}`);
   }
@@ -276,6 +286,12 @@ export function isIssuesAssignedEvent(
   return isIssuesEvent(context) && context.eventAction === "assigned";
 }
 
+export function isPushEvent(
+  context: GitHubContext,
+): context is AutomationContext & { payload: PushEvent } {
+  return context.eventName === "push";
+}
+
 // Type guard to check if context is an entity context (has entityNumber and isPR)
 export function isEntityContext(
   context: GitHubContext,

test/modes/detector.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it } from "bun:test";
 import { detectMode } from "../../src/modes/detector";
 import type { GitHubContext } from "../../src/github/context";
+import { isPushEvent } from "../../src/github/context";
 
 describe("detectMode with enhanced routing", () => {
   const baseContext = {
@@ -257,4 +258,65 @@ describe("detectMode with enhanced routing", () => {
       expect(detectMode(context)).toBe("tag");
     });
   });
+
+  describe("Push Events", () => {
+    it("should use agent mode for push events", () => {
+      const context: GitHubContext = {
+        ...baseContext,
+        eventName: "push",
+        payload: {} as any,
+        inputs: { ...baseContext.inputs, prompt: "Merge main into stale PRs" },
+      };
+
+      expect(detectMode(context)).toBe("agent");
+    });
+
+    it("should throw error when track_progress is used with push event", () => {
+      const context: GitHubContext = {
+        ...baseContext,
+        eventName: "push",
+        payload: {} as any,
+        inputs: { ...baseContext.inputs, trackProgress: true },
+      };
+
+      expect(() => detectMode(context)).toThrow(
+        /track_progress is only supported /,
+      );
+    });
+  });
+
+  describe("isPushEvent type guard", () => {
+    it("should return true for push events", () => {
+      const context: GitHubContext = {
+        ...baseContext,
+        eventName: "push",
+        payload: {} as any,
+      };
+
+      expect(isPushEvent(context)).toBe(true);
+    });
+
+    it("should return false for non-push events", () => {
+      const issueContext: GitHubContext = {
+        ...baseContext,
+        eventName: "issues",
+        eventAction: "opened",
+        payload: { issue: { number: 1, body: "Test" } } as any,
+        entityNumber: 1,
+        isPR: false,
+      };
+
+      expect(isPushEvent(issueContext)).toBe(false);
+    });
+
+    it("should return false for workflow_dispatch events", () => {
+      const context: GitHubContext = {
+        ...baseContext,
+        eventName: "workflow_dispatch",
+        payload: {} as any,
+      };
+
+      expect(isPushEvent(context)).toBe(false);
+    });
+  });
 });

test/modes/registry.test.ts

@@ -60,6 +60,15 @@ describe("Mode Registry", () => {
     expect(mode.name).toBe("agent");
   });
 
+  test("getMode auto-detects agent for push event", () => {
+    const pushContext = createMockAutomationContext({
+      eventName: "push",
+    });
+    const mode = getMode(pushContext);
+    expect(mode).toBe(agentMode);
+    expect(mode.name).toBe("agent");
+  });
+
   test("getMode auto-detects agent for repository_dispatch with client_payload", () => {
     const contextWithPayload = createMockAutomationContext({
       eventName: "repository_dispatch",