feat: let agents work with PDFs, ZIPs, and other files

apps/mobile/app.config.ts

@@ -142,12 +142,13 @@ const sharingPlugin: NonNullable<ExpoConfig["plugins"]>[number] = [
         supportsText: true,
         supportsWebUrlWithMaxCount: 1,
         supportsImageWithMaxCount: 8,
+        supportsFileWithMaxCount: 8,
       },
     },
     android: {
       enabled: true,
-      singleShareMimeTypes: ["text/plain", "image/*"],
-      multipleShareMimeTypes: ["image/*"],
+      singleShareMimeTypes: ["*/*"],
+      multipleShareMimeTypes: ["*/*"],
     },
   },
 ];

apps/mobile/src/components/ComposerAttachmentStrip.tsx

@@ -2,12 +2,13 @@ import { SymbolView } from "../components/AppSymbol";
 import { Image, Pressable, ScrollView, View } from "react-native";
 import { useThemeColor } from "../lib/useThemeColor";
 
-import type { DraftComposerImageAttachment } from "../lib/composerImages";
+import { AppText as Text } from "./AppText";
+import type { DraftComposerAttachment } from "../lib/composerImages";
 
 export interface ComposerAttachmentStripProps {
-  /** Attachment images to display. */
-  readonly attachments: ReadonlyArray<DraftComposerImageAttachment>;
-  /** Called when the user taps the remove button on an image. */
+  /** Attachments to display. */
+  readonly attachments: ReadonlyArray<DraftComposerAttachment>;
+  /** Called when the user removes an attachment. */
   readonly onRemove: (imageId: string) => void;
   /** Called when the user taps on an image thumbnail to preview it. */
   readonly onPressImage?: (previewUri: string) => void;
@@ -20,8 +21,7 @@ export interface ComposerAttachmentStripProps {
 }
 
 /**
- * A horizontally-scrollable strip of image attachment thumbnails with remove
- * buttons.  Used by both the thread composer and the new-task draft screen.
+ * Attachment thumbnails used by the thread composer and the new-task draft screen.
  */
 export function ComposerAttachmentStrip(props: ComposerAttachmentStripProps) {
   const subtleBg = useThemeColor("--color-subtle");
@@ -42,37 +42,56 @@ export function ComposerAttachmentStrip(props: ComposerAttachmentStripProps) {
       className="grow-0"
     >
       <View className="flex-row gap-2.5">
-        {props.attachments.map((image) => (
+        {props.attachments.map((attachment) => (
           <View
-            key={image.id}
+            key={attachment.id}
             className="relative"
             style={{
               paddingTop: removeButtonGutter,
               paddingRight: removeButtonGutter,
             }}
           >
-            <Pressable
-              onPress={props.onPressImage ? () => props.onPressImage!(image.previewUri) : undefined}
-            >
-              <Image
-                source={{ uri: image.previewUri }}
+            {attachment.type === "image" ? (
+              <Pressable
+                onPress={
+                  props.onPressImage ? () => props.onPressImage!(attachment.previewUri) : undefined
+                }
+              >
+                <Image
+                  source={{ uri: attachment.previewUri }}
+                  style={{
+                    width: size,
+                    height: size,
+                    borderRadius: radius,
+                    backgroundColor: subtleBg,
+                  }}
+                  resizeMode="cover"
+                />
+              </Pressable>
+            ) : (
+              <View
+                className="items-center justify-center gap-1 px-2"
                 style={{
                   width: size,
                   height: size,
                   borderRadius: radius,
                   backgroundColor: subtleBg,
                 }}
-                resizeMode="cover"
-              />
-            </Pressable>
+              >
+                <SymbolView name="doc.text" size={22} tintColor="#a3a3a3" type="monochrome" />
+                <Text className="w-full text-center text-2xs text-foreground" numberOfLines={1}>
+                  {attachment.name}
+                </Text>
+              </View>
+            )}
             <Pressable
               className="absolute h-[22px] w-[22px] items-center justify-center rounded-[11px] bg-black/55"
               style={{
                 top: removeButtonPlacement === "gutter" ? 0 : 4,
                 right: removeButtonPlacement === "gutter" ? 0 : 4,
               }}
               hitSlop={6}
-              onPress={() => props.onRemove(image.id)}
+              onPress={() => props.onRemove(attachment.id)}
             >
               <SymbolView
                 name="xmark"

apps/mobile/src/features/sharing/IncomingShareProvider.tsx

@@ -17,6 +17,7 @@ import {
 } from "./incoming-share-model";
 import { createIncomingSharePayloadReader } from "./incoming-share-native";
 import { IncomingShareInbox } from "./incoming-share-inbox";
+import { persistComposerAttachmentFile } from "../../lib/composerImages";
 import {
   loadIncomingShareDrafts,
   removeIncomingShareDraft,
@@ -54,7 +55,7 @@ const getIncomingSharePayloads = createIncomingSharePayloadReader({
   readPayloads: getSharedPayloads,
 });
 
-async function resolvedPayloadsForImages(): Promise<ReadonlyArray<ResolvedSharePayload>> {
+async function resolvedPayloadsForFiles(): Promise<ReadonlyArray<ResolvedSharePayload>> {
   try {
     return await getResolvedSharedPayloadsAsync();
   } catch (error) {
@@ -84,6 +85,11 @@ async function readBase64(uri: string): Promise<string> {
   return new File(uri).base64();
 }
 
+async function readFileSize(uri: string): Promise<number> {
+  const { File } = await import("expo-file-system");
+  return new File(uri).size ?? 0;
+}
+
 async function removeOwnedFile(uri: string): Promise<void> {
   if (!uri.startsWith("file:")) {
     return;
@@ -99,21 +105,19 @@ async function removeOwnedFile(uri: string): Promise<void> {
   }
 }
 
-async function removeReplayedImagePayloadFiles(
-  payloads: ReadonlyArray<SharePayload>,
-): Promise<void> {
+async function removeReplayedPayloadFiles(payloads: ReadonlyArray<SharePayload>): Promise<void> {
   const uris = new Set<string>();
   for (const payload of payloads) {
-    if (payload.shareType === "image") {
+    if (["image", "file", "audio", "video"].includes(payload.shareType)) {
       uris.add(payload.value);
     }
   }
   if (uris.size === 0) {
     return;
   }
-  const resolvedPayloads = await resolvedPayloadsForImages();
+  const resolvedPayloads = await resolvedPayloadsForFiles();
   for (const payload of resolvedPayloads) {
-    if (payload.shareType === "image" && payload.contentUri) {
+    if (["image", "file", "audio", "video"].includes(payload.shareType) && payload.contentUri) {
       uris.add(payload.contentUri);
     }
   }
@@ -131,14 +135,18 @@ const incomingShareInbox = new IncomingShareInbox({
   clearPayloads: clearSharedPayloads,
   buildDraft: async ({ payloads, id, createdAt }) => {
     const cleanupUris = new Set<string>();
-    const resolvedPayloads = payloads.some((payload) => payload.shareType === "image")
-      ? await resolvedPayloadsForImages()
+    const resolvedPayloads = payloads.some((payload) =>
+      ["image", "file", "audio", "video"].includes(payload.shareType),
+    )
+      ? await resolvedPayloadsForFiles()
       : [];
     const draft = await buildIncomingShareDraft({
       payloads,
       resolvedPayloads,
       fileReader: {
         readBase64,
+        persistFile: persistComposerAttachmentFile,
+        readSize: readFileSize,
         removeOwnedFile: (uri) => {
           cleanupUris.add(uri);
         },
@@ -153,7 +161,7 @@ const incomingShareInbox = new IncomingShareInbox({
       },
     };
   },
-  cleanupReplayedPayloads: removeReplayedImagePayloadFiles,
+  cleanupReplayedPayloads: removeReplayedPayloadFiles,
   idForPayloads: incomingShareIdForPayloads,
   now: () => new Date().toISOString(),
   onClearError: (error) => {

apps/mobile/src/features/sharing/incoming-share-model.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it, vi } from "@effect/vitest";
 import {
   PROVIDER_SEND_TURN_MAX_ATTACHMENTS,
+  PROVIDER_SEND_TURN_MAX_FILE_BYTES,
   PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 } from "@t3tools/contracts";
 import type { ResolvedSharePayload, SharePayload } from "expo-sharing";
@@ -96,6 +97,107 @@ describe("incoming native shares", () => {
     expect(hasIncomingShareContent(result)).toBe(false);
   });
 
+  it("keeps a shared PDF on disk without converting its contents to base64", async () => {
+    const file: SharePayload = {
+      shareType: "file",
+      value: "file:///shared/report.pdf",
+      mimeType: "application/pdf",
+    };
+    const readBase64 = vi.fn(async () => "unused");
+    const persistFile = vi.fn(async () => "file:///documents/report.pdf");
+    const removeOwnedFile = vi.fn(async () => undefined);
+
+    const result = await buildIncomingShareDraft({
+      id: "share-report",
+      createdAt: "2026-07-15T10:00:00.000Z",
+      payloads: [file],
+      resolvedPayloads: [
+        {
+          ...file,
+          contentUri: file.value,
+          contentType: "file",
+          contentMimeType: "application/pdf",
+          contentSize: 42,
+          originalName: "report.pdf",
+        },
+      ],
+      fileReader: { readBase64, persistFile, removeOwnedFile },
+    });
+
+    expect(result.attachments).toEqual([
+      {
+        id: "share-report:file:0",
+        type: "file",
+        name: "report.pdf",
+        mimeType: "application/pdf",
+        sizeBytes: 42,
+        fileUri: "file:///documents/report.pdf",
+      },
+    ]);
+    expect(readBase64).not.toHaveBeenCalled();
+    expect(persistFile).toHaveBeenCalledWith(file.value, "report.pdf");
+    expect(removeOwnedFile).toHaveBeenCalledWith(file.value);
+  });
+
+  it("rejects shared files that exceed the generic attachment limit", async () => {
+    const file: SharePayload = {
+      shareType: "file",
+      value: "file:///shared/huge.zip",
+      mimeType: "application/zip",
+    };
+    const persistFile = vi.fn(async () => "file:///documents/huge.zip");
+    const removeOwnedFile = vi.fn(async () => undefined);
+
+    const result = await buildIncomingShareDraft({
+      id: "share-huge",
+      createdAt: "2026-07-15T10:00:00.000Z",
+      payloads: [file],
+      resolvedPayloads: [
+        {
+          ...file,
+          contentUri: file.value,
+          contentType: "file",
+          contentMimeType: "application/zip",
+          contentSize: PROVIDER_SEND_TURN_MAX_FILE_BYTES + 1,
+          originalName: "huge.zip",
+        },
+      ],
+      fileReader: {
+        readBase64: async () => "unused",
+        persistFile,
+        removeOwnedFile,
+      },
+    });
+
+    expect(result.attachments).toEqual([]);
+    expect(result.warnings).toEqual(["'huge.zip' exceeds the 50 MB attachment limit."]);
+    expect(persistFile).not.toHaveBeenCalled();
+    expect(removeOwnedFile).toHaveBeenCalledWith(file.value);
+  });
+
+  it("reports an unreadable shared file without calling it oversized", async () => {
+    const file: SharePayload = {
+      shareType: "file",
+      value: "file:///shared/empty.txt",
+      mimeType: "text/plain",
+    };
+
+    const result = await buildIncomingShareDraft({
+      id: "share-empty",
+      createdAt: "2026-07-15T10:00:00.000Z",
+      payloads: [file],
+      resolvedPayloads: [],
+      fileReader: {
+        readBase64: async () => "unused",
+        readSize: async () => 0,
+        removeOwnedFile: async () => undefined,
+      },
+    });
+
+    expect(result.attachments).toEqual([]);
+    expect(result.warnings).toEqual(["'empty.txt' is empty or could not be read."]);
+  });
+
   it("releases every temporary file when a share exceeds the attachment limit", async () => {
     const payloads = Array.from({ length: PROVIDER_SEND_TURN_MAX_ATTACHMENTS + 1 }, (_, index) => ({
       shareType: "image" as const,