extension-object-storage

Installation
SKILL.md

Object Storage

Object storage extension for Caffeine AI.

Overview

This skill adds off-chain file/object storage with on-chain references. The MixinObjectStorage mixin provides infrastructure for file operations; you track uploaded files in your own data structures using Storage.ExternalBlob.

Required Setup Checklist

All four steps are mandatory. Skipping any one causes 403 Forbidden: Invalid payload at upload time.

  1. mops dependency — add caffeineai-object-storage to mops.toml under [dependencies].
  2. Mixin invocationinclude MixinObjectStorage() in main.mo (imported from "mo:caffeineai-object-storage/Mixin").
  3. Storage.ExternalBlob types — every data field that represents a file MUST use Storage.ExternalBlob, never Text.
  4. Frontend npm package@caffeineai/object-storage installed and ExternalBlob.fromBytes(bytes, file.type, file.name) used at the call site.

CRITICAL: The frontend package (@caffeineai/object-storage) does NOT work without the backend mops package (caffeineai-object-storage). Installing only the npm package and not the mops package causes silent upload failures (403 from the storage gateway). You MUST install both together.

Backend

Installs
3.4K
First Seen
Apr 4, 2026
extension-object-storage — caffeinelabs/skills