1. Overview
Media is awkward over REST — multipart bodies, large payloads, derivatives. MCP smooths it: media.upload returns a stable attachment id you can use with later tools.
2. AI enhancement
3. Upload tool
tools/media.upload.ts typescript
server.tool('media.upload', 'Upload an image with AI-generated alt text.', {
url: z.string().url(),
title: z.string().optional(),
}, async ({ url, title }) => {
const blob = await fetch(url).then(r => r.blob())
const form = new FormData()
form.set('file', blob, title ?? 'upload.png')
const wp = await wpPost('/wp/v2/media', form)
const alt = await visionDescribe(blob)
await wpPatch(`/wp/v2/media/${wp.id}`, { alt_text: alt })
return { content: [{ type:'text', text: `Uploaded #${wp.id} • alt: ${alt}` }] }
})4. Metadata & AI
Request
request.json json
{ "name":"media.upload", "arguments": { "url":"https://example.com/hero.jpg" } } Response
response.json json
{ "content":[{ "type":"text", "text":"Uploaded #482 • alt: A laptop on a wooden desk" }] }5. Workflow example
Ask the agent to "import every image from this Google Doc and attach them to draft #128." With media.upload + posts.update, the whole workflow is two tool calls.