trpc

trpc is a skill for Claude Code from bobmatnyc/claude-mpm-skills. It costs 23 tokens per session (12,321 once invoked), scanned A, original, MIT.

A guide to tRPC, a TypeScript and JavaScript system for calling server procedures from a client with shared types. It covers routers, input validation, context, middleware, errors, client setup, and React integration.

In plain words
What is it for?
Use it to design typed API procedures, validate inputs, add server middleware, manage context, handle errors, and connect React clients.
Why use it?
It helps the client and server agree on procedure names, inputs, and outputs, reducing mismatches between frontend calls and backend code.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

Needs its repository: it reads a path above its own folder, which exists only inside the repository. The line is import type { AppRouter } from '../server/trpc';.

Good fit Use it to design typed API procedures, validate inputs, add server middleware, manage context, handle errors, and connect React clients.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/bobmatnyc/claude-mpm-skills
agentmods
npx agentmods add skills/bobmatnyc/claude-mpm-skills/trpc

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for trpc

README.md
[![agentmods](https://agentmods.dev/badge/skills/bobmatnyc/claude-mpm-skills/trpc/github.svg)](https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/trpc)
Your own site
<a href="https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/trpc"><img src="https://agentmods.dev/badge/skills/bobmatnyc/claude-mpm-skills/trpc/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for trpc

Your own site · 80×15
<a href="https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/trpc"><img src="https://agentmods.dev/badge/skills/bobmatnyc/claude-mpm-skills/trpc.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 23 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 12,321 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 943
    Skill allows unbounded resource consumption (API calls, storage, compute). Without rate limits or quotas, a compromised or misbehaving agent can cause denial-of-service or cost overruns.
    Fix: Set explicit rate limits, timeouts, and resource quotas for API calls, file operations, and compute. Implement circuit breakers for runaway loops.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00023 $0.12321
Opus 5 $0.00012 $0.06161
Sonnet 5 $0.00005 $0.02464
Haiku 4.5 $0.00002 $0.01232

Measured 9d ago against content hash 92690cf6cc23, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

trpc scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

await fetch(uploadUrl, {
toolchains/typescript/api/trpc/SKILL.md · 2,103 lines

How it starts

The opening of the file, as written. The whole thing — 2,103 lines — stays where its author put it; the contents beside it link to each section on GitHub.

tRPC - End-to-End Type Safety


progressive_disclosure: entry_point: summary sections: - id: summary title: "tRPC Overview" tokens: 70 next: [when_to_use, quick_start] - id: when_to_use title: "When to Use tRPC" tokens: 150 next: [quick_start, core_concepts] - id: quick_start title: "Quick Start" tokens: 300 next: [core_concepts, router_definition] - id: core_concepts title: "Core Concepts" tokens: 400 next: [router_definition, procedures] - id: router_definition title: "Router Definition" tokens: 350 next: [procedures, context] - id: procedures title: "Procedures (Query & Mutation)" tokens: 400 next: [input_validation, context] - id: input_validation title: "Input Validation with Zod" tokens: 350 next: [context, middleware] - id: context title: "Context Management" tokens: 400 next: [middleware, error_handling] - id: middleware title: "Middleware" tokens: 400 next: [error_handling, client_setup] - id: error_handling title: "Error Handling" tokens: 350 next: [client_setup, react_integration] - id: client_setup title: "Client Setup" tokens: 400 next: [react_integration, nextjs_integration] - id: react_integration title: "React Query Integration" tokens: 450 next: [nextjs_integration, subscriptions] - id: nextjs_integration title: "Next.js App Router Integration" tokens: 500 next: [subscriptions, file_uploads] - id: subscriptions title: "Real-time Subscriptions" tokens: 400 next: [file_uploads, batching] - id: file_uploads title: "File Uploads" tokens: 300 next: [batching, typescript_inference] - id: batching title: "Batch Requests & Data Loaders" tokens: 350 next: [typescript_inference, testing] - id: typescript_inference title: "TypeScript Inference Patterns" tokens: 300 next: [testing, production_patterns] - id: testing title: "Testing Strategies" tokens: 400 next: [production_patterns, comparison] - id: production_patterns title: "Production Patterns" tokens: 450 next: [comparison, migration] - id: comparison title: "Comparison with REST & GraphQL" tokens: 250 next: [migration, best_practices] - id: migration title: "Migration from REST" tokens: 300 next: [best_practices] - id: best_practices title: "Best Practices & Performance" tokens: 400

Read the full file on GitHub · 2,103 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 2,103 lines · 23 tokens per session scan A 92690cf6cc23

Subscribe to this mod's changes

trpc is a skill published in the GitHub repository bobmatnyc/claude-mpm-skills (75 stars, last pushed 1mo ago), licensed MIT. It adds 23 tokens to every session and 12,321 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Related

Other skills, from other repositories

adapter-express

Mount tRPC as Express middleware with createExpressMiddleware() from @trpc/server/adapters/express. Access Express req/res in createContext via CreateExpressContextOptions. Mount at a path prefix like app.use('/trpc', ...). Avoid global express.json() conflicting with tRPC body parsing for FormData.

trpc/trpc · 67 tokens

trpc-router

Entry point for all tRPC skills. Decision tree routing by task: initTRPC.create(), t.router(), t.procedure, createTRPCClient, adapters, subscriptions, React Query, Next.js, links, middleware, validators, error handling, caching, FormData.

trpc/trpc · 59 tokens

stripe-projects

Use after E2B sandbox/API access has been provisioned through Stripe Projects and the user needs to use the resulting E2B API key with the E2B CLI, JavaScript SDK, Python SDK, or Code Interpreter SDK.

e2b-dev/E2B · 51 tokens

chat-sdk

Build multi-platform chat bots with Chat SDK (chat npm package). Use when developers want to (1) Build a Slack, Teams, Google Chat, Discord, Telegram, GitHub, Linear, or WhatsApp bot, (2) Use Chat SDK to handle mentions, direct messages, subscribed threads, reactions, slash commands, cards, modals, files, or AI…

vercel-labs/open-agents · 191 tokens

nestjs-expert

Creates and configures NestJS modules, controllers, services, DTOs, guards, and interceptors for enterprise-grade TypeScript backend applications. Use when building NestJS REST APIs or GraphQL services, implementing dependency injection, scaffolding modular architecture, adding JWT/Passport authentication, integrating…

Jeffallan/claude-skills · 107 tokens

fastify-best-practices

Guides development of Fastify Node.js backend servers and REST APIs using TypeScript or JavaScript. Use when building, configuring, or debugging a Fastify application — including defining routes, implementing plugins, setting up JSON Schema validation, handling errors, optimising performance, managing authentication…

mcollina/skills · 137 tokens