diff --git a/TODO.md b/TODO.md
index 6fa688d..945a79b 100644
--- a/TODO.md
+++ b/TODO.md
@@ -118,7 +118,7 @@ This file is the single source of truth for roadmap and delivery progress.
 
 ### MVP1 Suggested Branch Order
 
-- [~] [P1] `todo/mvp1-media-foundation`:
+- [x] [P1] `todo/mvp1-media-foundation`:
   media model, artwork entity, grouping primitives (gallery/album/category/tag), rendition slots
 - [ ] [P1] `todo/mvp1-media-upload-pipeline`:
   S3/local upload adapter, media processing presets, metadata input flows, admin media CRUD UI
@@ -269,6 +269,7 @@ This file is the single source of truth for roadmap and delivery progress.
 - [2026-02-11] `gaertan` inspiration to reuse: S3 object strategy with signed delivery, commission type/options/extras/custom-input modeling, request-status kanban mapping, and gallery rendition/color extraction patterns.
 - [2026-02-11] MVP1 media foundation started: portfolio domain models (`MediaAsset`, `Artwork`, galleries/albums/categories/tags, rendition links) plus initial admin `/media` and `/portfolio` data views.
 - [2026-02-11] `prisma migrate dev --name media_foundation` can fail when DB endpoint is unreachable; apply this named migration once `DATABASE_URL` host is reachable again.
+- [2026-02-11] MVP1 media foundation now includes baseline create/link workflows in admin (`/media`, `/portfolio`), seeded sample portfolio entities, and schema/service test coverage.
 
 ## How We Use This File
 
diff --git a/apps/admin/src/app/media/page.tsx b/apps/admin/src/app/media/page.tsx
index fbcf217..b189fbb 100644
--- a/apps/admin/src/app/media/page.tsx
+++ b/apps/admin/src/app/media/page.tsx
@@ -1,17 +1,109 @@
-import { getMediaFoundationSummary, listMediaAssets } from "@cms/db"
+import { createMediaAsset, getMediaFoundationSummary, listMediaAssets } from "@cms/db"
+import { Button } from "@cms/ui/button"
+import { revalidatePath } from "next/cache"
+import { redirect } from "next/navigation"
 
 import { AdminShell } from "@/components/admin-shell"
 import { requirePermissionForRoute } from "@/lib/route-guards"
 
 export const dynamic = "force-dynamic"
 
-export default async function MediaManagementPage() {
+type SearchParamsInput = Record<string, string | string[] | undefined>
+
+function readFirstValue(value: string | string[] | undefined): string | null {
+  if (Array.isArray(value)) {
+    return value[0] ?? null
+  }
+
+  return value ?? null
+}
+
+function readField(formData: FormData, field: string): string {
+  const value = formData.get(field)
+  return typeof value === "string" ? value.trim() : ""
+}
+
+function readOptionalField(formData: FormData, field: string): string | undefined {
+  const value = readField(formData, field)
+  return value.length > 0 ? value : undefined
+}
+
+function readTags(formData: FormData, field: string): string[] {
+  const raw = readField(formData, field)
+
+  if (!raw) {
+    return []
+  }
+
+  return raw
+    .split(",")
+    .map((item) => item.trim())
+    .filter((item) => item.length > 0)
+}
+
+function redirectWithState(params: { notice?: string; error?: string }) {
+  const query = new URLSearchParams()
+
+  if (params.notice) {
+    query.set("notice", params.notice)
+  }
+
+  if (params.error) {
+    query.set("error", params.error)
+  }
+
+  const value = query.toString()
+  redirect(value ? `/media?${value}` : "/media")
+}
+
+async function createMediaAssetAction(formData: FormData) {
+  "use server"
+
+  await requirePermissionForRoute({
+    nextPath: "/media",
+    permission: "media:write",
+    scope: "team",
+  })
+
+  try {
+    await createMediaAsset({
+      title: readField(formData, "title"),
+      type: readField(formData, "type"),
+      description: readOptionalField(formData, "description"),
+      altText: readOptionalField(formData, "altText"),
+      source: readOptionalField(formData, "source"),
+      copyright: readOptionalField(formData, "copyright"),
+      author: readOptionalField(formData, "author"),
+      tags: readTags(formData, "tags"),
+    })
+  } catch {
+    redirectWithState({
+      error: "Failed to create media asset. Validate required fields and try again.",
+    })
+  }
+
+  revalidatePath("/media")
+  revalidatePath("/portfolio")
+  redirectWithState({ notice: "Media asset created." })
+}
+
+export default async function MediaManagementPage({
+  searchParams,
+}: {
+  searchParams: Promise<SearchParamsInput>
+}) {
   const role = await requirePermissionForRoute({
     nextPath: "/media",
     permission: "media:read",
     scope: "team",
   })
-  const [summary, assets] = await Promise.all([getMediaFoundationSummary(), listMediaAssets(20)])
+  const [resolvedSearchParams, summary, assets] = await Promise.all([
+    searchParams,
+    getMediaFoundationSummary(),
+    listMediaAssets(20),
+  ])
+  const notice = readFirstValue(resolvedSearchParams.notice)
+  const error = readFirstValue(resolvedSearchParams.error)
 
   return (
     <AdminShell
@@ -21,6 +113,18 @@ export default async function MediaManagementPage() {
       title="Media"
       description="Media foundation baseline for assets, artwork renditions, and grouping metadata."
     >
+      {notice ? (
+        <section className="rounded-xl border border-emerald-300 bg-emerald-50 px-4 py-3 text-sm text-emerald-800">
+          {notice}
+        </section>
+      ) : null}
+
+      {error ? (
+        <section className="rounded-xl border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-800">
+          {error}
+        </section>
+      ) : null}
+
       <section className="grid gap-3 sm:grid-cols-2 xl:grid-cols-3">
         <article className="rounded-xl border border-neutral-200 p-4">
           <p className="text-xs uppercase tracking-[0.2em] text-neutral-500">Media Assets</p>
@@ -43,6 +147,86 @@ export default async function MediaManagementPage() {
         </article>
       </section>
 
+      <section className="rounded-xl border border-neutral-200 p-6">
+        <h2 className="text-xl font-medium">Create Media Asset</h2>
+        <form action={createMediaAssetAction} className="mt-4 space-y-3">
+          <div className="grid gap-3 md:grid-cols-2">
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Title</span>
+              <input
+                name="title"
+                required
+                minLength={1}
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Type</span>
+              <select
+                name="type"
+                defaultValue="artwork"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              >
+                <option value="artwork">artwork</option>
+                <option value="banner">banner</option>
+                <option value="promotion">promotion</option>
+                <option value="video">video</option>
+                <option value="gif">gif</option>
+                <option value="generic">generic</option>
+              </select>
+            </label>
+          </div>
+          <label className="space-y-1">
+            <span className="text-xs text-neutral-600">Description</span>
+            <textarea
+              name="description"
+              rows={3}
+              className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+          </label>
+          <div className="grid gap-3 md:grid-cols-2">
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Alt text</span>
+              <input
+                name="altText"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Author</span>
+              <input
+                name="author"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+          </div>
+          <div className="grid gap-3 md:grid-cols-2">
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Source</span>
+              <input
+                name="source"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Copyright</span>
+              <input
+                name="copyright"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+          </div>
+          <label className="space-y-1">
+            <span className="text-xs text-neutral-600">Tags (comma-separated)</span>
+            <input
+              name="tags"
+              className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+          </label>
+          <Button type="submit">Create media asset</Button>
+        </form>
+      </section>
+
       <section className="rounded-xl border border-neutral-200 p-6">
         <div className="flex items-center justify-between gap-2">
           <h2 className="text-xl font-medium">Recent Media Assets</h2>
diff --git a/apps/admin/src/app/portfolio/page.tsx b/apps/admin/src/app/portfolio/page.tsx
index b644b25..85595ad 100644
--- a/apps/admin/src/app/portfolio/page.tsx
+++ b/apps/admin/src/app/portfolio/page.tsx
@@ -1,17 +1,218 @@
-import { listArtworks } from "@cms/db"
+import {
+  attachArtworkRendition,
+  createAlbum,
+  createArtwork,
+  createCategory,
+  createGallery,
+  createTag,
+  linkArtworkToGrouping,
+  listArtworks,
+  listMediaAssets,
+  listMediaFoundationGroups,
+} from "@cms/db"
+import { Button } from "@cms/ui/button"
+import { revalidatePath } from "next/cache"
+import { redirect } from "next/navigation"
 
 import { AdminShell } from "@/components/admin-shell"
 import { requirePermissionForRoute } from "@/lib/route-guards"
 
 export const dynamic = "force-dynamic"
 
-export default async function PortfolioPage() {
+type SearchParamsInput = Record<string, string | string[] | undefined>
+type GroupType = "gallery" | "album" | "category" | "tag"
+
+function readField(formData: FormData, key: string): string {
+  const value = formData.get(key)
+  return typeof value === "string" ? value.trim() : ""
+}
+
+function readOptionalField(formData: FormData, key: string): string | undefined {
+  const value = readField(formData, key)
+  return value.length > 0 ? value : undefined
+}
+
+function readFirstValue(value: string | string[] | undefined): string | null {
+  if (Array.isArray(value)) {
+    return value[0] ?? null
+  }
+
+  return value ?? null
+}
+
+function slugify(input: string): string {
+  return input
+    .toLowerCase()
+    .trim()
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/^-+|-+$/g, "")
+    .slice(0, 180)
+}
+
+function redirectWithState(params: { notice?: string; error?: string }) {
+  const query = new URLSearchParams()
+
+  if (params.notice) {
+    query.set("notice", params.notice)
+  }
+
+  if (params.error) {
+    query.set("error", params.error)
+  }
+
+  const value = query.toString()
+  redirect(value ? `/portfolio?${value}` : "/portfolio")
+}
+
+async function requireWritePermission() {
+  await requirePermissionForRoute({
+    nextPath: "/portfolio",
+    permission: "media:write",
+    scope: "team",
+  })
+}
+
+async function createArtworkAction(formData: FormData) {
+  "use server"
+
+  await requireWritePermission()
+
+  const title = readField(formData, "title")
+  const slug = slugify(readField(formData, "slug") || title)
+
+  try {
+    await createArtwork({
+      title,
+      slug,
+      description: readOptionalField(formData, "description"),
+      medium: readOptionalField(formData, "medium"),
+      dimensions: readOptionalField(formData, "dimensions"),
+      framing: readOptionalField(formData, "framing"),
+      availability: readOptionalField(formData, "availability"),
+      year: (() => {
+        const raw = readField(formData, "year")
+        return raw ? Number(raw) : undefined
+      })(),
+    })
+  } catch {
+    redirectWithState({ error: "Failed to create artwork." })
+  }
+
+  revalidatePath("/portfolio")
+  redirectWithState({ notice: "Artwork created." })
+}
+
+async function createGroupAction(formData: FormData) {
+  "use server"
+
+  await requireWritePermission()
+
+  const type = readField(formData, "groupType") as GroupType
+  const name = readField(formData, "name")
+  const slug = slugify(readField(formData, "slug") || name)
+
+  try {
+    if (type === "gallery") {
+      await createGallery({
+        name,
+        slug,
+        description: readOptionalField(formData, "description"),
+      })
+    } else if (type === "album") {
+      await createAlbum({
+        name,
+        slug,
+        description: readOptionalField(formData, "description"),
+      })
+    } else if (type === "category") {
+      await createCategory({
+        name,
+        slug,
+        description: readOptionalField(formData, "description"),
+      })
+    } else {
+      await createTag({
+        name,
+        slug,
+      })
+    }
+  } catch {
+    redirectWithState({ error: "Failed to create grouping entity." })
+  }
+
+  revalidatePath("/portfolio")
+  redirectWithState({ notice: `${type} created.` })
+}
+
+async function linkArtworkGroupAction(formData: FormData) {
+  "use server"
+
+  await requireWritePermission()
+
+  const artworkId = readField(formData, "artworkId")
+  const groupType = readField(formData, "groupType") as GroupType
+  const groupId = readField(formData, "groupId")
+
+  try {
+    await linkArtworkToGrouping({
+      artworkId,
+      groupType,
+      groupId,
+    })
+  } catch {
+    redirectWithState({ error: "Failed to link artwork to grouping." })
+  }
+
+  revalidatePath("/portfolio")
+  redirectWithState({ notice: "Artwork linked to grouping." })
+}
+
+async function attachRenditionAction(formData: FormData) {
+  "use server"
+
+  await requireWritePermission()
+
+  try {
+    await attachArtworkRendition({
+      artworkId: readField(formData, "artworkId"),
+      mediaAssetId: readField(formData, "mediaAssetId"),
+      slot: readField(formData, "slot"),
+      width: (() => {
+        const raw = readField(formData, "width")
+        return raw ? Number(raw) : undefined
+      })(),
+      height: (() => {
+        const raw = readField(formData, "height")
+        return raw ? Number(raw) : undefined
+      })(),
+      isPrimary: readField(formData, "isPrimary") === "true",
+    })
+  } catch {
+    redirectWithState({ error: "Failed to attach artwork rendition." })
+  }
+
+  revalidatePath("/portfolio")
+  redirectWithState({ notice: "Rendition attached." })
+}
+
+export default async function PortfolioPage({
+  searchParams,
+}: {
+  searchParams: Promise<SearchParamsInput>
+}) {
   const role = await requirePermissionForRoute({
     nextPath: "/portfolio",
     permission: "media:read",
     scope: "team",
   })
-  const artworks = await listArtworks(30)
+  const [resolvedSearchParams, artworks, mediaAssets, groups] = await Promise.all([
+    searchParams,
+    listArtworks(30),
+    listMediaAssets(200),
+    listMediaFoundationGroups(),
+  ])
+  const notice = readFirstValue(resolvedSearchParams.notice)
+  const error = readFirstValue(resolvedSearchParams.error)
 
   return (
     <AdminShell
@@ -21,6 +222,217 @@ export default async function PortfolioPage() {
       title="Portfolio"
       description="Artwork foundation with rendition slots and grouping relations."
     >
+      {notice ? (
+        <section className="rounded-xl border border-emerald-300 bg-emerald-50 px-4 py-3 text-sm text-emerald-800">
+          {notice}
+        </section>
+      ) : null}
+
+      {error ? (
+        <section className="rounded-xl border border-red-300 bg-red-50 px-4 py-3 text-sm text-red-800">
+          {error}
+        </section>
+      ) : null}
+
+      <section className="rounded-xl border border-neutral-200 p-6">
+        <h2 className="text-xl font-medium">Create Artwork</h2>
+        <form action={createArtworkAction} className="mt-4 space-y-3">
+          <div className="grid gap-3 md:grid-cols-2">
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Title</span>
+              <input
+                name="title"
+                required
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+            <label className="space-y-1">
+              <span className="text-xs text-neutral-600">Slug (optional)</span>
+              <input
+                name="slug"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              />
+            </label>
+          </div>
+          <label className="space-y-1">
+            <span className="text-xs text-neutral-600">Description</span>
+            <textarea
+              name="description"
+              rows={3}
+              className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+          </label>
+          <div className="grid gap-3 md:grid-cols-2 xl:grid-cols-4">
+            <input
+              name="medium"
+              placeholder="Medium"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+            <input
+              name="dimensions"
+              placeholder="Dimensions"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+            <input
+              name="year"
+              type="number"
+              placeholder="Year"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+            <input
+              name="framing"
+              placeholder="Framing"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+          </div>
+          <input
+            name="availability"
+            placeholder="Availability"
+            className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+          />
+          <Button type="submit">Create artwork</Button>
+        </form>
+      </section>
+
+      <section className="rounded-xl border border-neutral-200 p-6">
+        <h2 className="text-xl font-medium">Create Group Entity</h2>
+        <form action={createGroupAction} className="mt-4 space-y-3">
+          <div className="grid gap-3 md:grid-cols-3">
+            <select
+              name="groupType"
+              defaultValue="gallery"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            >
+              <option value="gallery">gallery</option>
+              <option value="album">album</option>
+              <option value="category">category</option>
+              <option value="tag">tag</option>
+            </select>
+            <input
+              name="name"
+              required
+              placeholder="Name"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+            <input
+              name="slug"
+              placeholder="Slug (optional)"
+              className="rounded border border-neutral-300 px-3 py-2 text-sm"
+            />
+          </div>
+          <textarea
+            name="description"
+            rows={2}
+            placeholder="Description (optional)"
+            className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+          />
+          <Button type="submit">Create group</Button>
+        </form>
+      </section>
+
+      <section className="rounded-xl border border-neutral-200 p-6">
+        <h2 className="text-xl font-medium">Link Artwork To Group</h2>
+        <div className="mt-4 grid gap-4 lg:grid-cols-2">
+          {(
+            [
+              { type: "gallery" as const, label: "Gallery", items: groups.galleries },
+              { type: "album" as const, label: "Album", items: groups.albums },
+              { type: "category" as const, label: "Category", items: groups.categories },
+              { type: "tag" as const, label: "Tag", items: groups.tags },
+            ] as const
+          ).map((groupConfig) => (
+            <form
+              key={groupConfig.type}
+              action={linkArtworkGroupAction}
+              className="space-y-3 rounded border border-neutral-200 p-4"
+            >
+              <h3 className="text-sm font-semibold">{groupConfig.label} Link</h3>
+              <input type="hidden" name="groupType" value={groupConfig.type} />
+              <select
+                name="artworkId"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              >
+                {artworks.map((artwork) => (
+                  <option key={`${groupConfig.type}-${artwork.id}`} value={artwork.id}>
+                    {artwork.title}
+                  </option>
+                ))}
+              </select>
+              <select
+                name="groupId"
+                className="w-full rounded border border-neutral-300 px-3 py-2 text-sm"
+              >
+                {groupConfig.items.map((group) => (
+                  <option key={`${groupConfig.type}-${group.id}`} value={group.id}>
+                    {group.name}
+                  </option>
+                ))}
+              </select>
+              <Button type="submit">Link artwork</Button>
+            </form>
+          ))}
+        </div>
+      </section>
+
+      <section className="rounded-xl border border-neutral-200 p-6">
+        <h2 className="text-xl font-medium">Attach Artwork Rendition Slot</h2>
+        <form
+          action={attachRenditionAction}
+          className="mt-4 grid gap-3 md:grid-cols-3 xl:grid-cols-6"
+        >
+          <select name="artworkId" className="rounded border border-neutral-300 px-3 py-2 text-sm">
+            {artworks.map((artwork) => (
+              <option key={artwork.id} value={artwork.id}>
+                {artwork.title}
+              </option>
+            ))}
+          </select>
+          <select
+            name="mediaAssetId"
+            className="rounded border border-neutral-300 px-3 py-2 text-sm"
+          >
+            {mediaAssets.map((asset) => (
+              <option key={asset.id} value={asset.id}>
+                {asset.title}
+              </option>
+            ))}
+          </select>
+          <select
+            name="slot"
+            defaultValue="thumbnail"
+            className="rounded border border-neutral-300 px-3 py-2 text-sm"
+          >
+            <option value="thumbnail">thumbnail</option>
+            <option value="card">card</option>
+            <option value="full">full</option>
+            <option value="custom">custom</option>
+          </select>
+          <input
+            name="width"
+            type="number"
+            placeholder="width"
+            className="rounded border border-neutral-300 px-3 py-2 text-sm"
+          />
+          <input
+            name="height"
+            type="number"
+            placeholder="height"
+            className="rounded border border-neutral-300 px-3 py-2 text-sm"
+          />
+          <select
+            name="isPrimary"
+            defaultValue="false"
+            className="rounded border border-neutral-300 px-3 py-2 text-sm"
+          >
+            <option value="false">not primary</option>
+            <option value="true">primary</option>
+          </select>
+          <div className="md:col-span-3 xl:col-span-6">
+            <Button type="submit">Attach rendition</Button>
+          </div>
+        </form>
+      </section>
+
       <section className="rounded-xl border border-neutral-200 p-6">
         <div className="flex items-center justify-between gap-2">
           <h2 className="text-xl font-medium">Artworks</h2>
diff --git a/packages/content/src/media.test.ts b/packages/content/src/media.test.ts
new file mode 100644
index 0000000..4d23183
--- /dev/null
+++ b/packages/content/src/media.test.ts
@@ -0,0 +1,51 @@
+import { describe, expect, it } from "vitest"
+
+import {
+  attachArtworkRenditionInputSchema,
+  createGroupingInputSchema,
+  createMediaAssetInputSchema,
+  linkArtworkGroupingInputSchema,
+} from "./media"
+
+describe("media schemas", () => {
+  it("accepts supported media asset type payload", () => {
+    const parsed = createMediaAssetInputSchema.parse({
+      type: "artwork",
+      title: "Artwork",
+      tags: ["tag-a"],
+    })
+
+    expect(parsed.type).toBe("artwork")
+    expect(parsed.tags).toEqual(["tag-a"])
+  })
+
+  it("validates grouping link payload", () => {
+    const parsed = linkArtworkGroupingInputSchema.parse({
+      artworkId: "f40f4bcc-7148-45d7-a19d-856f7146a47e",
+      groupType: "gallery",
+      groupId: "f4e094df-0edf-4d5a-8b7b-c51f09cae95e",
+    })
+
+    expect(parsed.groupType).toBe("gallery")
+  })
+
+  it("enforces rendition slot enum", () => {
+    const parsed = attachArtworkRenditionInputSchema.parse({
+      artworkId: "f40f4bcc-7148-45d7-a19d-856f7146a47e",
+      mediaAssetId: "f4e094df-0edf-4d5a-8b7b-c51f09cae95e",
+      slot: "thumbnail",
+    })
+
+    expect(parsed.slot).toBe("thumbnail")
+  })
+
+  it("supports grouping defaults", () => {
+    const parsed = createGroupingInputSchema.parse({
+      name: "Featured",
+      slug: "featured",
+    })
+
+    expect(parsed.sortOrder).toBe(0)
+    expect(parsed.isVisible).toBe(true)
+  })
+})
diff --git a/packages/content/src/media.ts b/packages/content/src/media.ts
index c08c0f2..9456de0 100644
--- a/packages/content/src/media.ts
+++ b/packages/content/src/media.ts
@@ -33,7 +33,33 @@ export const createArtworkInputSchema = z.object({
   availability: z.string().max(180).optional(),
 })
 
+export const createGroupingInputSchema = z.object({
+  name: z.string().min(1).max(180),
+  slug: z.string().min(1).max(180),
+  description: z.string().max(5000).optional(),
+  sortOrder: z.number().int().min(0).default(0),
+  isVisible: z.boolean().default(true),
+})
+
+export const linkArtworkGroupingInputSchema = z.object({
+  artworkId: z.string().uuid(),
+  groupType: z.enum(["gallery", "album", "category", "tag"]),
+  groupId: z.string().uuid(),
+})
+
+export const attachArtworkRenditionInputSchema = z.object({
+  artworkId: z.string().uuid(),
+  mediaAssetId: z.string().uuid(),
+  slot: artworkRenditionSlotSchema,
+  width: z.number().int().positive().optional(),
+  height: z.number().int().positive().optional(),
+  isPrimary: z.boolean().default(false),
+})
+
 export type MediaAssetType = z.infer<typeof mediaAssetTypeSchema>
 export type ArtworkRenditionSlot = z.infer<typeof artworkRenditionSlotSchema>
 export type CreateMediaAssetInput = z.infer<typeof createMediaAssetInputSchema>
 export type CreateArtworkInput = z.infer<typeof createArtworkInputSchema>
+export type CreateGroupingInput = z.infer<typeof createGroupingInputSchema>
+export type LinkArtworkGroupingInput = z.infer<typeof linkArtworkGroupingInputSchema>
+export type AttachArtworkRenditionInput = z.infer<typeof attachArtworkRenditionInputSchema>
diff --git a/packages/db/prisma/seed.ts b/packages/db/prisma/seed.ts
index 5daa7ec..ca2dce3 100644
--- a/packages/db/prisma/seed.ts
+++ b/packages/db/prisma/seed.ts
@@ -13,6 +13,75 @@ async function main() {
     },
   })
 
+  const media = await db.mediaAsset.upsert({
+    where: { storageKey: "seed/artwork-welcome.jpg" },
+    update: {},
+    create: {
+      type: "artwork",
+      title: "Seed Artwork Image",
+      altText: "Seed artwork placeholder",
+      tags: ["seed", "portfolio"],
+      storageKey: "seed/artwork-welcome.jpg",
+      mimeType: "image/jpeg",
+      isPublished: true,
+    },
+  })
+
+  const artwork = await db.artwork.upsert({
+    where: { slug: "seed-artwork-welcome" },
+    update: {},
+    create: {
+      title: "Seed Artwork",
+      slug: "seed-artwork-welcome",
+      description: "Baseline seeded artwork for MVP1 media foundation.",
+      medium: "Digital",
+      year: 2026,
+      availability: "available",
+      isPublished: true,
+    },
+  })
+
+  const gallery = await db.gallery.upsert({
+    where: { slug: "featured" },
+    update: {},
+    create: {
+      name: "Featured",
+      slug: "featured",
+      description: "Featured artwork selection.",
+      isVisible: true,
+    },
+  })
+
+  await db.artworkGallery.upsert({
+    where: {
+      artworkId_galleryId: {
+        artworkId: artwork.id,
+        galleryId: gallery.id,
+      },
+    },
+    create: {
+      artworkId: artwork.id,
+      galleryId: gallery.id,
+    },
+    update: {},
+  })
+
+  await db.artworkRendition.upsert({
+    where: {
+      artworkId_slot: {
+        artworkId: artwork.id,
+        slot: "thumbnail",
+      },
+    },
+    create: {
+      artworkId: artwork.id,
+      mediaAssetId: media.id,
+      slot: "thumbnail",
+      isPrimary: true,
+    },
+    update: {},
+  })
+
   await db.systemSetting.upsert({
     where: { key: "public.header_banner" },
     update: {},
diff --git a/packages/db/src/index.ts b/packages/db/src/index.ts
index bcbf4be..a73079f 100644
--- a/packages/db/src/index.ts
+++ b/packages/db/src/index.ts
@@ -1,5 +1,18 @@
 export { db } from "./client"
-export { getMediaFoundationSummary, listArtworks, listMediaAssets } from "./media-foundation"
+export {
+  attachArtworkRendition,
+  createAlbum,
+  createArtwork,
+  createCategory,
+  createGallery,
+  createMediaAsset,
+  createTag,
+  getMediaFoundationSummary,
+  linkArtworkToGrouping,
+  listArtworks,
+  listMediaAssets,
+  listMediaFoundationGroups,
+} from "./media-foundation"
 export {
   createPost,
   deletePost,
diff --git a/packages/db/src/media-foundation.test.ts b/packages/db/src/media-foundation.test.ts
new file mode 100644
index 0000000..025a596
--- /dev/null
+++ b/packages/db/src/media-foundation.test.ts
@@ -0,0 +1,93 @@
+import { beforeEach, describe, expect, it, vi } from "vitest"
+
+const { mockDb } = vi.hoisted(() => ({
+  mockDb: {
+    artworkGallery: { upsert: vi.fn() },
+    artworkAlbum: { upsert: vi.fn() },
+    artworkCategory: { upsert: vi.fn() },
+    artworkTag: { upsert: vi.fn() },
+    artworkRendition: { upsert: vi.fn() },
+    mediaAsset: { create: vi.fn() },
+    artwork: { create: vi.fn() },
+    gallery: { create: vi.fn() },
+    album: { create: vi.fn() },
+    category: { create: vi.fn() },
+    tag: { create: vi.fn() },
+  },
+}))
+
+vi.mock("./client", () => ({
+  db: mockDb,
+}))
+
+import {
+  attachArtworkRendition,
+  createArtwork,
+  createMediaAsset,
+  linkArtworkToGrouping,
+} from "./media-foundation"
+
+describe("media foundation service", () => {
+  beforeEach(() => {
+    for (const value of Object.values(mockDb)) {
+      if ("upsert" in value) {
+        value.upsert.mockReset()
+      }
+      if ("create" in value) {
+        value.create.mockReset()
+      }
+    }
+  })
+
+  it("routes grouping links to the correct link table", async () => {
+    mockDb.artworkAlbum.upsert.mockResolvedValue({ id: "link" })
+
+    await linkArtworkToGrouping({
+      artworkId: "f40f4bcc-7148-45d7-a19d-856f7146a47e",
+      groupType: "album",
+      groupId: "f4e094df-0edf-4d5a-8b7b-c51f09cae95e",
+    })
+
+    expect(mockDb.artworkAlbum.upsert).toHaveBeenCalledTimes(1)
+    expect(mockDb.artworkGallery.upsert).not.toHaveBeenCalled()
+  })
+
+  it("upserts rendition by artwork and slot", async () => {
+    mockDb.artworkRendition.upsert.mockResolvedValue({ id: "rendition" })
+
+    await attachArtworkRendition({
+      artworkId: "f40f4bcc-7148-45d7-a19d-856f7146a47e",
+      mediaAssetId: "f4e094df-0edf-4d5a-8b7b-c51f09cae95e",
+      slot: "thumbnail",
+      isPrimary: true,
+    })
+
+    expect(mockDb.artworkRendition.upsert).toHaveBeenCalledTimes(1)
+    expect(mockDb.artworkRendition.upsert.mock.calls[0]?.[0]).toMatchObject({
+      where: {
+        artworkId_slot: {
+          artworkId: "f40f4bcc-7148-45d7-a19d-856f7146a47e",
+          slot: "thumbnail",
+        },
+      },
+    })
+  })
+
+  it("parses and forwards media and artwork creation payloads", async () => {
+    mockDb.mediaAsset.create.mockResolvedValue({ id: "asset" })
+    mockDb.artwork.create.mockResolvedValue({ id: "artwork" })
+
+    await createMediaAsset({
+      type: "generic",
+      title: "Asset",
+      tags: [],
+    })
+    await createArtwork({
+      title: "Artwork",
+      slug: "artwork",
+    })
+
+    expect(mockDb.mediaAsset.create).toHaveBeenCalledTimes(1)
+    expect(mockDb.artwork.create).toHaveBeenCalledTimes(1)
+  })
+})
diff --git a/packages/db/src/media-foundation.ts b/packages/db/src/media-foundation.ts
index c5620aa..101938f 100644
--- a/packages/db/src/media-foundation.ts
+++ b/packages/db/src/media-foundation.ts
@@ -1,3 +1,11 @@
+import {
+  attachArtworkRenditionInputSchema,
+  createArtworkInputSchema,
+  createGroupingInputSchema,
+  createMediaAssetInputSchema,
+  linkArtworkGroupingInputSchema,
+} from "@cms/content"
+
 import { db } from "./client"
 
 export async function listMediaAssets(limit = 24) {
@@ -67,6 +75,169 @@ export async function listArtworks(limit = 24) {
   })
 }
 
+export async function listMediaFoundationGroups() {
+  const [galleries, albums, categories, tags] = await Promise.all([
+    db.gallery.findMany({
+      orderBy: [{ sortOrder: "asc" }, { name: "asc" }],
+    }),
+    db.album.findMany({
+      orderBy: [{ sortOrder: "asc" }, { name: "asc" }],
+    }),
+    db.category.findMany({
+      orderBy: [{ sortOrder: "asc" }, { name: "asc" }],
+    }),
+    db.tag.findMany({
+      orderBy: { name: "asc" },
+    }),
+  ])
+
+  return {
+    galleries,
+    albums,
+    categories,
+    tags,
+  }
+}
+
+export async function createMediaAsset(input: unknown) {
+  const payload = createMediaAssetInputSchema.parse(input)
+
+  return db.mediaAsset.create({
+    data: payload,
+  })
+}
+
+export async function createArtwork(input: unknown) {
+  const payload = createArtworkInputSchema.parse(input)
+
+  return db.artwork.create({
+    data: payload,
+  })
+}
+
+export async function createGallery(input: unknown) {
+  const payload = createGroupingInputSchema.parse(input)
+
+  return db.gallery.create({
+    data: payload,
+  })
+}
+
+export async function createAlbum(input: unknown) {
+  const payload = createGroupingInputSchema.parse(input)
+
+  return db.album.create({
+    data: payload,
+  })
+}
+
+export async function createCategory(input: unknown) {
+  const payload = createGroupingInputSchema.parse(input)
+
+  return db.category.create({
+    data: payload,
+  })
+}
+
+export async function createTag(input: unknown) {
+  const payload = createGroupingInputSchema
+    .pick({
+      name: true,
+      slug: true,
+    })
+    .parse(input)
+
+  return db.tag.create({
+    data: payload,
+  })
+}
+
+export async function linkArtworkToGrouping(input: unknown) {
+  const payload = linkArtworkGroupingInputSchema.parse(input)
+
+  if (payload.groupType === "gallery") {
+    return db.artworkGallery.upsert({
+      where: {
+        artworkId_galleryId: {
+          artworkId: payload.artworkId,
+          galleryId: payload.groupId,
+        },
+      },
+      create: {
+        artworkId: payload.artworkId,
+        galleryId: payload.groupId,
+      },
+      update: {},
+    })
+  }
+
+  if (payload.groupType === "album") {
+    return db.artworkAlbum.upsert({
+      where: {
+        artworkId_albumId: {
+          artworkId: payload.artworkId,
+          albumId: payload.groupId,
+        },
+      },
+      create: {
+        artworkId: payload.artworkId,
+        albumId: payload.groupId,
+      },
+      update: {},
+    })
+  }
+
+  if (payload.groupType === "category") {
+    return db.artworkCategory.upsert({
+      where: {
+        artworkId_categoryId: {
+          artworkId: payload.artworkId,
+          categoryId: payload.groupId,
+        },
+      },
+      create: {
+        artworkId: payload.artworkId,
+        categoryId: payload.groupId,
+      },
+      update: {},
+    })
+  }
+
+  return db.artworkTag.upsert({
+    where: {
+      artworkId_tagId: {
+        artworkId: payload.artworkId,
+        tagId: payload.groupId,
+      },
+    },
+    create: {
+      artworkId: payload.artworkId,
+      tagId: payload.groupId,
+    },
+    update: {},
+  })
+}
+
+export async function attachArtworkRendition(input: unknown) {
+  const payload = attachArtworkRenditionInputSchema.parse(input)
+
+  return db.artworkRendition.upsert({
+    where: {
+      artworkId_slot: {
+        artworkId: payload.artworkId,
+        slot: payload.slot,
+      },
+    },
+    create: payload,
+    update: {
+      mediaAssetId: payload.mediaAssetId,
+      width: payload.width,
+      height: payload.height,
+      isPrimary: payload.isPrimary,
+    },
+  })
+}
+
 export async function getMediaFoundationSummary() {
   const [mediaAssets, artworks, galleries, albums, categories, tags] = await Promise.all([
     db.mediaAsset.count(),