new·The score now tells you which way it movedA brain's exam only ever grows: its own material writes questions, and so does every question a real caller asked and did not get answered. The score is a percentage over that growing set, so a brain that learned more could post a smaller number — and this week three did. One of them answered two MORE questions than the week before and showed eighteen points less. Printed as a single percentage, that reads as decline to a reader and as punishment to anyone who contributes material.all news →
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tRPC

Answer questions about tRPC as documented today: defining routers and procedures, input and output validation, context and middleware, error handling and formatting, the React Query and TanStack integrations, server adapters for each framework, subscriptions, and end-to-end type inference.

1,011 notes · updated 2026-08-12 · trained 79%

since last sitting: +32 newly passed — this brain is learning · the verified changelog →

use this brain
# sign in to get a token
$ claude mcp add --transport http mozg \
https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/trpc — …
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Ask it things like

answers 30/35 on its latest exam · anti-bluff 2/5
What method adds middleware to a procedure, and what does middleware receive and return?Context & Middleware✓
What is the base procedure type you get from initTRPC, and how do you create queries and mutations from it?Defining Routers & Procedures✓
How do you export the tRPC router type to the client for end-to-end type safety?End-to-End Type Inference✓
How do you attach a validator to a procedure's input, and what is the method name?Input & Output Validation✓
What is the minimal setup to create a tRPC client with vanilla TypeScript (no framework)?Client Setup✓
What design pattern does tRPC use for building procedures—can you chain methods on the same procedure object?Defining Routers & Procedures✓
How do you nest multiple routers together into a single router?Defining Routers & Procedures✓
What is the TRPCError class, and what parameters does it require?Error Handling & Formatting✓

What it can answer

35 coverage checks
79%
Answers 32 of the exam's 40 questionsIt answers 32 questions, 32 more than last time, out of an exam that grew by 40.Nothing it used to answer has stopped working.
✓Defining Routers & Procedures4 / 4
✓Input & Output Validation4 / 4
▲Context & Middleware3 / 4
✓End-to-End Type Inference3 / 3
✓Error Handling & Formatting3 / 3
▲Next.js Integration3 / 4
▲React Query Integration3 / 4
▲Server Adapters3 / 4
✓Client Setup2 / 2
▲Subscriptions2 / 3
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Attacks survived

re-run weekly · 2026-08-10
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✓injection-corpusevery active note scanned — no steering language
✓secret-corpusevery active note scanned — no keys or credentials

heuristic scans against known attack classes — measured and dated, not a promise of unpoisonability

Inside

  • E2E type safety with tRPC · end-to-end type inference
  • tRPC response handler location in Next.js · server adapters/next-app-dir
  • pnpm dev command starts Next.js and WebSocket server · setup/nextjs-app-router
  • Next.js Prisma WebSockets starter example setup · setup/nextjs-app-router
  • WebSocket and subscription support in Next.js starter · subscriptions
  • tRPC routers location in Next.js starter · defining routers and procedures
  • next-prisma-starter Render deployment · setup/nextjs-app-router
  • next-prisma-starter example project setup · setup/nextjs-app-router
  • next-prisma-starter key file paths · setup/nextjs-app-router
  • next-prisma-starter pnpm commands · setup/nextjs-app-router
  • next-prisma-starter requirements · setup/nextjs-app-router
  • TodoMVC example setup command · setup/nextjs-app-router
  • TodoMVC dx command · setup/nextjs-app-router
  • TodoMVC example stack · setup/nextjs-app-router

Licence

CC BY-NC-SA 4.0

Use it, copy it, build on it, with credit. Selling it is not allowed.