Upload local or chat-provided image files into a Mantle site through the companion plugin. Use when an operator asks to add an image/file to a Mantle entry and the file is available locally or as a host-provided attachment path.
How this skill is triggered — by the user, by Claude, or both
Slash command
/mantle-companion-upload:mantle-companion-uploadThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
Use this skill when an operator wants to upload a chat image, generated
Use this skill when an operator wants to upload a chat image, generated image, screenshot, or local image file into a deployed Mantle site.
create_media_upload -> signed upload URLs -> direct PUT -> commit_media_upload.siteDefaults.media.purposes; never invent purpose strings.asset.id is the value to put into *AssetId fields
and x-mantle-ref: media_assets references.post-coverpage-heroproduct-coverproduct-imageMANTLE_WORKER_ORIGIN or
the tool argument workerOrigin; otherwise ask for it.MANTLE_STAFF_BEARER or
the tool argument staffBearer; otherwise ask for a fresh Staff MCP
bearer from the site owner/operator.Call the bundled MCP tool:
upload_mantle_image_from_file
Provide:
filePathpurposealtcaptionworkerOrigin and staffBearer only when environment
variables are missing or intentionally overriddenThe tool shells out to the released aotter-mantle-media-tools helper.
That helper creates AVIF/WebP/JPEG variants, asks the Mantle Worker for
signed upload URLs, uploads each variant directly to storage, and commits
the asset over Staff MCP.
Report:
asset.idIf the upload fails with a Mantle diagnostic:
MEDIA_PURPOSE_REJECTED: use an existing purpose or ask the coding
agent to add a new purpose to src/mantleConfig.ts.MEDIA_VARIANTS_INCOMPLETE: the helper/runtime variant policies do
not match; stop and ask for a coding-agent fix.MEDIA_VARIANT_SIZE_EXCEEDED: retry with smaller maxEdge, or ask
the coding agent to adjust the media policy.Do not retry by embedding the file in a normal MCP tool call.
npx claudepluginhub aotter/mantle-starters --plugin mantle-companion-uploadCreates, edits, and optimizes skills for Claude Code, including drafting, evaluating with test prompts, iterating on performance, and improving skill descriptions for better triggering accuracy.