Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add DeckardGer/tanstack-agent-skills --skill tanstack-startgit clone --depth 1 https://github.com/DeckardGer/tanstack-agent-skillsWrote 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.
[](https://agentmods.dev/skills/deckardger/tanstack-agent-skills/tanstack-start)<a href="https://agentmods.dev/skills/deckardger/tanstack-agent-skills/tanstack-start"><img src="https://agentmods.dev/badge/skills/deckardger/tanstack-agent-skills/tanstack-start/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.
<a href="https://agentmods.dev/skills/deckardger/tanstack-agent-skills/tanstack-start"><img src="https://agentmods.dev/badge/skills/deckardger/tanstack-agent-skills/tanstack-start.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00043 | $0.00944 |
| Opus 5.5 | $0.00017 | $0.00378 |
| Sonnet 5.5 | $0.00009 | $0.00189 |
| Haiku 4.5 | $0.00004 | $0.00094 |
Grade A, and why
tanstack-start-best-practices scanned grade A with 0 findings 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 1mo 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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 110 lines — stays where its author put it; the contents beside it link to each section on GitHub.
TanStack Start Best Practices
Comprehensive guidelines for implementing TanStack Start patterns in full-stack React applications. These rules cover server functions, middleware, SSR, authentication, and deployment.
When to Apply
- Creating server functions for data mutations
- Setting up middleware for auth/logging
- Configuring SSR and hydration
- Implementing authentication flows
- Handling errors across client/server boundary
- Organizing full-stack code
- Deploying to various platforms
Rule Categories by Priority
| Priority | Category | Rules | Impact |
|---|---|---|---|
| CRITICAL | Server Functions | 5 rules | Core data mutation patterns |
| CRITICAL | Security | 4 rules | Prevents vulnerabilities |
| HIGH | Middleware | 4 rules | Request/response handling |
| HIGH | Authentication | 4 rules | Secure user sessions |
| MEDIUM | API Routes | 1 rule | External endpoint patterns |
| MEDIUM | SSR | 5 rules | Server rendering patterns |
| MEDIUM | Error Handling | 3 rules | Graceful failure handling |
| MEDIUM | Environment | 1 rule | Configuration management |
| LOW | File Organization | 3 rules | Maintainable code structure |
| LOW | Deployment | 2 rules | Production readiness |
Quick Reference
Server Functions (Prefix: sf-)
sf-create-server-fn— Use createServerFn for server-side logicsf-input-validation— Always validate server function inputssf-method-selection— Choose appropriate HTTP methodsf-error-handling— Handle errors in server functionssf-response-headers— Customize response headers when needed
Security (Prefix: sec-)
sec-validate-inputs— Validate all user inputs with schemassec-auth-middleware— Protect routes with auth middlewaresec-sensitive-data— Keep secrets server-side onlysec-csrf-protection— Implement CSRF protection for mutations
Middleware (Prefix: mw-)
mw-request-middleware— Use request middleware for cross-cutting concernsmw-function-middleware— Use function middleware for server functionsmw-context-flow— Properly pass context through middlewaremw-composability— Compose middleware effectively
What ships with it
32 files 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.
- rules/api-routes.md 6.6 KB
- rules/auth-cookie-security.md 3.2 KB
- rules/auth-route-protection.md 4.5 KB
- rules/auth-server-functions.md 3.2 KB
- rules/auth-session-management.md 4.9 KB
- rules/deploy-adapters.md 3.8 KB
- rules/deploy-env-config.md 3.9 KB
- rules/env-functions.md 5.3 KB
- rules/err-not-found.md 3.7 KB
- rules/err-redirects.md 3.4 KB
- rules/err-server-errors.md 4.9 KB
- rules/file-functions-file.md 3.5 KB
- rules/file-separation.md 4.2 KB
- rules/file-shared-validation.md 3.7 KB
- rules/mw-composability.md 4.8 KB
- rules/mw-context-flow.md 3.6 KB
- rules/mw-function-middleware.md 3.9 KB
- rules/mw-request-middleware.md 4.3 KB
- rules/sec-auth-middleware.md 3.9 KB
- rules/sec-csrf-protection.md 3.5 KB
- rules/sec-sensitive-data.md 3.5 KB
- rules/sec-validate-inputs.md 3.2 KB
- rules/sf-create-server-fn.md 3.9 KB
- rules/sf-error-handling.md 3.2 KB
- rules/sf-input-validation.md 4.6 KB
- rules/sf-method-selection.md 2.4 KB
- rules/sf-response-headers.md 2.7 KB
- rules/ssr-data-loading.md 3.4 KB
- rules/ssr-hydration-safety.md 4.8 KB
- rules/ssr-prerender.md 4.9 KB
- rules/ssr-selective.md 3.9 KB
- rules/ssr-streaming.md 5.4 KB
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.
- 1mo ago Changed e0600061e22d
- 1mo ago First seen · 110 lines · 43 tokens per session scan A 9fc7b6f7733d
tanstack-start-best-practices is a skill published in the GitHub repository DeckardGer/tanstack-agent-skills (224 stars, last pushed 1mo ago), licensed MIT. It adds 43 tokens to every session and 944 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
nextjs-pages-router
Set up tRPC in Next.js Pages Router with createNextApiHandler, createTRPCNext, withTRPC HOC, SSR via ssr option and ssrPrepass, SSG via createServerSideHelpers with getStaticProps, and server-side helpers for getServerSideProps prefetching.
subscriptions
Set up real-time event streams with async generator subscriptions using .subscription(async function() { yield }). SSE via httpSubscriptionLink is recommended over WebSocket. Use tracked(id, data) from @trpc/server for reconnection recovery with lastEventId. WebSocket via wsLink and createWSClient from @trpc/client…
links
Configure the tRPC client link chain: httpLink, httpBatchLink, httpBatchStreamLink, splitLink, loggerLink, wsLink, createWSClient, httpSubscriptionLink, unstablelocalLink, retryLink. Choose the right terminating link. Route subscriptions via splitLink. Build custom links for SOA routing. Link options: url, headers…
middlewares
Create and compose tRPC middleware with t.procedure.use(), extend context via opts.next({ ctx }), build reusable middleware with .concat() and .unstablepipe(), define base procedures like publicProcedure and authedProcedure. Access raw input with getRawInput(). Logging, timing, OTEL tracing patterns.
non-json-content-types
Handle FormData, file uploads, Blob, Uint8Array, and ReadableStream inputs in tRPC mutations. Use octetInputParser from @trpc/server/http for binary data. Route non-JSON requests with splitLink and isNonJsonSerializable() from @trpc/client. FormData and binary inputs only work with mutations (POST).
server-side-calls
Call tRPC procedures directly from server code using t.createCallerFactory() and router.createCaller(context) for integration testing, internal server logic, and custom API endpoints. Catch TRPCError and extract HTTP status with getHTTPStatusCodeFromError(). Error handling via onError option.