diff --git a/skills/trpc-router/SKILL.md b/skills/trpc-router/SKILL.md
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+---
+name: trpc-router
+description: "Scaffold a complete tRPC v11 router for a named entity in this monorepo. Use when creating a new tRPC router, adding API endpoint procedures, or scaffolding CRUD routes. Trigger on phrases like 'create a router for X', 'scaffold X routes', 'I need CRUD for X', 'add X endpoints', or any mention of 'router', 'route', 'CRUD', 'procedure', or 'endpoint' alongside an entity name. Do NOT trigger on edits to existing routers, general API design discussions, config changes, or architecture debates."
+---
+
+# tRPC Router Scaffolder
+
+Scaffold a complete new tRPC router for a named entity. Invoked via `/trpc-router <entity> [options]` or automatically when the user wants a new API route or endpoint for a named entity.
+
+## Step -1 — Help flag and interactive mode
+
+**Handle these before anything else.**
+
+### --help
+
+If `--help` or `-h` appears in the arguments, output the following and **stop** — do not scaffold:
+
+```
+Usage: /trpc-router <entity> [options]
+
+Scaffolds a complete tRPC v11 router for a named entity.
+
+Arguments:
+  entity                 The entity name (any casing — e.g. post, ProductVariant, order-item)
+
+Options:
+  --procedures <value>   Which procedures to generate (default: all)
+                           all       → all, byId, create, update, delete
+                           query     → all, byId
+                           mutation  → create, update, delete
+                           Or pick individually: byId, create, update, delete
+
+  --auth <mode>          Auth mode for procedures (default: mixed)
+                           mixed     → queries use publicProcedure, mutations use protectedProcedure
+                           public    → all procedures use publicProcedure
+                           protected → all procedures use protectedProcedure
+
+  --with-schema          Also append a Drizzle table + Zod schemas to packages/db/src/schema.ts
+                         (You'll be asked for column definitions before anything is written)
+
+  --no-tests             Skip generating the test file
+
+  --guided               Step through all options interactively before scaffolding
+
+  --help, -h             Show this help text
+
+Examples:
+  /trpc-router post
+  /trpc-router comment --procedures query --auth public
+  /trpc-router orderItem --procedures mutation --with-schema --no-tests
+  /trpc-router user --auth protected --guided
+```
+
+### Interactive guided mode
+
+Trigger guided mode when **either** of these is true:
+- No entity name was provided (e.g. bare `/trpc-router` or "scaffold a router")
+- `--guided` is in the arguments
+
+**Guided flow:**
+
+1. **Entity name** *(skip if already provided)*
+   Ask: `What entity would you like to scaffold a router for?`
+   Wait for a response.
+
+2. **Procedures**
+   Ask:
+   ```
+   Which procedures should I generate? (default: all)
+     all       → all, byId, create, update, delete
+     query     → all, byId only
+     mutation  → create, update, delete only
+     Or list specific ones: byId, create, delete
+   ```
+   Accept a blank reply or "default" to mean `all`.
+
+3. **Auth mode**
+   Ask:
+   ```
+   Auth mode? (default: mixed)
+     mixed     → queries public, mutations protected
+     public    → all procedures public
+     protected → all procedures protected
+   ```
+   Accept a blank reply or "default" to mean `mixed`.
+
+4. **Schema**
+   Ask: `Generate a Drizzle table + Zod schema in schema.ts? (y/n, default: n)`
+   Accept y/yes to set `--with-schema`.
+
+5. **Tests**
+   Ask: `Generate a test file? (y/n, default: y)`
+   Accept n/no to set `--no-tests`.
+
+6. **Confirm** — summarise the resolved options before scaffolding:
+   ```
+   Ready to scaffold:
+     Entity:     <entity>
+     Procedures: <procedures>
+     Auth:       <auth>
+     Schema:     <yes/no>
+     Tests:      <yes/no>
+
+   Proceed? (y/n)
+   ```
+   If the user says no or asks to change something, go back to the relevant question.
+
+Once confirmed, continue to Step 0 with the collected options.
+
+---
+
+## Step 0 — Pre-flight reads
+
+Before generating any files, read these four files (always):
+
+- `packages/api/src/root.ts` — router registration pattern, existing routers, collision check
+- `packages/api/src/test-helpers.ts` — `makeTestCaller` signature and context shape
+- `packages/api/src/trpc.ts` — available procedure types and context fields
+- `packages/api/src/index.ts` — package exports (check if the new router needs type re-exports)
+
+If `--with-schema` was requested, also read:
+
+- `packages/db/src/schema.ts` — find the exact insertion point, verify imports are not duplicated
+
+Do **not** read any files under `packages/api/src/router/` — they are template placeholders and may not exist.
+
+## Step 1 — Parse and validate the entity name
+
+Accept any casing and normalise:
+
+| Input | Normalised |
+|-------|-----------|
+| `ProductVariant` | `productVariant` |
+| `product-variant` | `productVariant` |
+| `comment` | `comment` |
+
+Derive these identifiers from the normalised name:
+
+- **Router key** (in `root.ts`): camelCase — e.g. `productVariant`
+- **Router file**: kebab-case — e.g. `product-variant.ts`
+- **Router export**: camelCase + `Router` — e.g. `productVariantRouter`
+- **Table/class name**: PascalCase — e.g. `ProductVariant`
+- **Zod schema names**: `Create<Entity>Schema`, `Update<Entity>Schema` — e.g. `CreateProductVariantSchema`, `UpdateProductVariantSchema`
+
+Check `root.ts` for a collision — if a router with the same key already exists, warn the user and abort. Confirm the result is a valid TypeScript identifier (alphanumeric, starts with a letter).
+
+## Step 2 — Resolve options
+
+| Option | Values | Default |
+|--------|--------|---------|
+| `--procedures` | `all`, `query`, `mutation`, or comma-separated list of: `all`, `byId`, `create`, `update`, `delete` | `all` (all five procedures) |
+| `--auth` | `public`, `protected`, `mixed` | `mixed` |
+| `--with-schema` | flag | off |
+| `--no-tests` | flag | off |
+
+**Procedure shortcuts:**
+- `all` → `all, byId, create, update, delete`
+- `query` → `all, byId`
+- `mutation` → `create, update, delete`
+
+When a subset is specified, omit unspecified procedures entirely — no stubs or comments for them.
+
+**Auth modes:**
+- `public` — all procedures use `publicProcedure`
+- `protected` — all procedures use `protectedProcedure`
+- `mixed` — queries (`all`, `byId`) use `publicProcedure`; mutations (`create`, `update`, `delete`) use `protectedProcedure`
+
+## Step 3 — Execution order
+
+This order is mandatory — the router imports from the schema, so the schema must exist first.
+
+1. **If `--with-schema`**: append table + Zod schema to `packages/db/src/schema.ts`
+2. Create `packages/api/src/router/<entity>.ts`
+3. Register the router in `packages/api/src/root.ts`
+4. **Unless `--no-tests`**: create `packages/api/src/router/<entity>.test.ts`
+
+## Step 4 — Generate files using the templates
+
+Read the relevant template files from the `templates/` folder adjacent to this skill. Each template is a markdown file — extract only the code block (the content inside the ` ```ts ``` ` fence), then substitute the entity placeholders before writing:
+
+- **Router** → read `templates/router.md`, write to `packages/api/src/router/<entity>.ts`
+- **Tests** → read `templates/test.md`, write to `packages/api/src/router/<entity>.test.ts`
+- **Schema** (only with `--with-schema`) → read `templates/schema.md`, append to `packages/db/src/schema.ts`
+
+Placeholder substitution:
+
+| Placeholder | Replace with |
+|-------------|-------------|
+| `<Entity>` | PascalCase entity name |
+| `<entity>` | camelCase entity name |
+| `<entity-kebab>` | kebab-case entity name (file names only) |
+
+**After substitution, apply these adjustments:**
+
+- Remove any imports that aren't used (e.g. omit `protectedProcedure` if `--auth public`; omit `Create<Entity>Schema` if `create` is not included)
+- Remove procedures not in the requested set — omit entirely, no stubs
+- Adjust `publicProcedure` / `protectedProcedure` per `--auth` mode
+- For `--with-schema`: ask the user for entity-specific column definitions before writing — do not generate columns without input
+
+**Confirm `root.ts` was updated** before presenting the checklist.
+
+---
+
+## Post-scaffolding checklist
+
+Present this after all files are generated:
+
+- [ ] Schema appended to `packages/db/src/schema.ts` *(only if `--with-schema`)*
+- [ ] Router created at `packages/api/src/router/<entity>.ts`
+- [ ] Router registered in `packages/api/src/root.ts`
+- [ ] Test file created at `packages/api/src/router/<entity>.test.ts` *(unless `--no-tests`)*
+- [ ] Run `pnpm typecheck`
+- [ ] Run `pnpm db:push` *(only if `--with-schema`)*
+- [ ] Run `pnpm test`
+
+---
+
+## Constraints
+
+- Use Australian/British English in all user-facing text
+- Zod imports are **always** from `"zod/v4"` — never from `"zod"`
+- TypeScript strict mode — no `any` and no `eslint-disable` comments in generated files; use `makeAuthenticatedCaller()` from `test-helpers` for mutation tests (protected procedures), use `makeTestCaller()` for query tests (public procedures)
+- Import ordering: `import type` first, then value imports — match the router template exactly
+- When a procedure subset is given, omit the rest entirely — no stubs or placeholder comments
diff --git a/skills/trpc-router/templates/router.md b/skills/trpc-router/templates/router.md
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+# Router Template
+
+Use to generate `packages/api/src/router/<entity-kebab>.ts`.
+
+Substitute all placeholders:
+- `<Entity>` → PascalCase (e.g. `ProductVariant`)
+- `<entity>` → camelCase (e.g. `productVariant`)
+
+After substitution, remove any imports that are unused given the selected `--procedures` and `--auth` options (e.g. omit `protectedProcedure` if `--auth public`; omit `Create<Entity>Schema` if `create` is excluded).
+
+```ts
+import type { TRPCRouterRecord } from "@trpc/server";
+import { z } from "zod/v4";
+
+import { desc, eq } from "@acme/db"; // desc: only if 'all' is included; eq: always
+import { Create<Entity>Schema, Update<Entity>Schema, <Entity> } from "@acme/db/schema"; // Omit Create<Entity>Schema if 'create' excluded; omit Update<Entity>Schema if 'update' excluded
+
+import { protectedProcedure, publicProcedure } from "../trpc";
+
+export const <entity>Router = {
+  all: publicProcedure.query(({ ctx }) => {
+    return ctx.db.query.<Entity>.findMany({
+      orderBy: desc(<Entity>.id),
+      limit: 10,
+    });
+  }),
+
+  byId: publicProcedure
+    .input(z.object({ id: z.string() }))
+    .query(({ ctx, input }) => {
+      return ctx.db.query.<Entity>.findFirst({
+        where: eq(<Entity>.id, input.id),
+      });
+    }),
+
+  create: protectedProcedure
+    .input(Create<Entity>Schema)
+    .mutation(({ ctx, input }) => {
+      return ctx.db.insert(<Entity>).values(input);
+    }),
+
+  update: protectedProcedure
+    .input(Update<Entity>Schema)
+    .mutation(({ ctx, input }) => {
+      const { id, ...data } = input;
+      return ctx.db.update(<Entity>).set(data).where(eq(<Entity>.id, id)).returning();
+    }),
+
+  delete: protectedProcedure.input(z.string()).mutation(({ ctx, input }) => {
+    return ctx.db.delete(<Entity>).where(eq(<Entity>.id, input));
+  }),
+} satisfies TRPCRouterRecord;
+```
diff --git a/skills/trpc-router/templates/schema.md b/skills/trpc-router/templates/schema.md
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+# Schema Template
+
+Append to `packages/db/src/schema.ts` — do **not** create a new file.
+
+The following imports are already present in `schema.ts` — do **not** duplicate them:
+- `import { sql } from "drizzle-orm"`
+- `import { pgTable } from "drizzle-orm/pg-core"`
+- `import { createInsertSchema } from "drizzle-zod"`
+- `import { z } from "zod/v4"`
+
+Ask the user for entity-specific column definitions (name, type, nullable, validation rules) before writing — do not generate columns without input.
+
+Substitute all placeholders:
+- `<Entity>` → PascalCase (e.g. `ProductVariant`)
+- `<entity>` → camelCase (e.g. `productVariant`)
+
+```ts
+export const <Entity> = pgTable("<entity>", (t) => ({
+  id: t.uuid().notNull().primaryKey().defaultRandom(),
+  // entity-specific columns here
+  createdAt: t.timestamp().defaultNow().notNull(),
+  updatedAt: t
+    .timestamp({ mode: "date", withTimezone: true })
+    .$onUpdateFn(() => new Date()),
+}));
+
+export const Create<Entity>Schema = createInsertSchema(<Entity>, {
+  // add per-field Zod overrides here if needed
+}).omit({
+  id: true,
+  createdAt: true,
+  updatedAt: true,
+});
+
+export const Update<Entity>Schema = createInsertSchema(<Entity>)
+  .omit({ createdAt: true, updatedAt: true })
+  .partial()
+  .required({ id: true });
+```
diff --git a/skills/trpc-router/templates/test.md b/skills/trpc-router/templates/test.md
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+# Test Template
+
+Use to generate `packages/api/src/router/<entity-kebab>.test.ts`.
+
+Substitute all placeholders:
+- `<Entity>` → PascalCase (e.g. `ProductVariant`)
+- `<entity>` → camelCase (e.g. `productVariant`)
+
+Fill `/* required fields */` with the actual column values needed to satisfy the schema's non-nullable constraints. Use valid RFC 4122 UUIDs for all UUID fields — never bare strings like `"test-uuid"` or zero-padded strings like `"00000000-0000-4000-8000-000000000001"` (the 3rd group must start with `[1-8]` for version, 4th group with `[89ab]` for variant). Use the pattern `"00000000-0000-4000-8000-00000000000X"` for readable test fixtures.
+
+Omit tests for procedures that were not included in `--procedures`.
+
+```ts
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import { eq } from "@acme/db";
+import { db } from "@acme/db/client";
+import { <Entity> } from "@acme/db/schema";
+
+import { makeAuthenticatedCaller, makeTestCaller } from "../test-helpers";
+
+vi.mock("@acme/db/client", async () => {
+  const { createMockDb } = await import("@acme/db/mocks");
+  return { db: await createMockDb() };
+});
+
+describe("<entity>Router", () => {
+  beforeEach(async () => {
+    // If <Entity> has FK dependencies, delete child tables first, then parents.
+    // See like.test.ts for an example (deletes Like then Post).
+    await db.delete(<Entity>);
+  });
+
+  it("should return all <entity>s", async () => {
+    const caller = makeTestCaller();
+    const result = await caller.<entity>.all();
+    expect(result).toEqual([]);
+  });
+
+  it("should fetch <entity> by id — found", async () => {
+    const record = { id: "00000000-0000-4000-8000-000000000001", /* required fields */ };
+    await db.insert(<Entity>).values(record);
+
+    const caller = makeTestCaller();
+    const result = await caller.<entity>.byId({ id: record.id });
+    expect(result?.id).toBe(record.id);
+  });
+
+  it("should fetch <entity> by id — not found", async () => {
+    const caller = makeTestCaller();
+    const result = await caller.<entity>.byId({ id: "00000000-0000-4000-8000-000000000099" });
+    expect(result).toBeUndefined();
+  });
+
+  it("should create a <entity>", async () => {
+    const caller = makeAuthenticatedCaller();
+
+    await caller.<entity>.create({ /* required fields */ });
+
+    const records = await db.select().from(<Entity>);
+    expect(records).toHaveLength(1);
+    expect(records[0]?./* field */).toBe(/* expected value */);
+  });
+
+  it("should update a <entity>", async () => {
+    const record = { id: "00000000-0000-4000-8000-000000000001", /* required fields */ };
+    await db.insert(<Entity>).values(record);
+
+    const caller = makeAuthenticatedCaller();
+    await caller.<entity>.update({ id: record.id, /* fields to update */ });
+
+    const [updated] = await db.select().from(<Entity>).where(eq(<Entity>.id, record.id));
+    expect(updated?./* updated field */).toBe(/* expected value */);
+  });
+
+  it("should delete a <entity>", async () => {
+    const record = { id: "00000000-0000-4000-8000-000000000001", /* required fields */ };
+    await db.insert(<Entity>).values(record);
+
+    const caller = makeAuthenticatedCaller();
+    await caller.<entity>.delete(record.id);
+
+    const records = await db.select().from(<Entity>);
+    expect(records).toHaveLength(0);
+  });
+});
+```