> Canonical URL: https://codingcat.dev/course/full-stack-ai-agents-typescript/lesson/agent-evals-guardrails-spend-caps-in-production

# Agent Evals, Guardrails & Spend Caps in Production | Full-Stack AI Agents in TypeScript (No Python Required) | CodingCat.dev Course

[🧶 Full-Stack AI Agents in TypeScript (No Python Required)](/course/full-stack-ai-agents-typescript)Section 1.5 · Lesson 5 of 5[← Prev Lesson](/course/full-stack-ai-agents-typescript/lesson/serverless-gpus-without-dockerfiles-runpod-flash)

# Agent Evals, Guardrails & Spend Caps in Production

![Full-Stack AI Agents in TypeScript Architecture Diagram](https://cdn.sanity.io/media-libraries/mlttp0BZbCpV/images/78383c8986667bc1eaa504786488d88f212929a8-1280x720.jpg?w=1920&h=1080&q=82&fit=max&auto=format)[@CodingCatDev62.5K / 100K Subscribers Goal](https://www.youtube.com/@codingcatdev?sub_confirmation=1)[Subscribe on YouTube→](https://www.youtube.com/@codingcatdev?sub_confirmation=1)[Watch on YouTube App ↗](https://www.youtube.com/watch?v=7d6iJHEPMZI&list=UUnKZ8gEb78zXKMi1ns-IQ2g)

## Defense-in-Depth for Public AI Endpoints

Every public AI route needs three guardrails before going live: per-IP/session rate limiting, strict max_tokens bounds, and provider-level hard spend caps.

Copied! 🐾📄 src/lib/guardrails.tstypescript

```
export function enforcePromptBudget(prompt: string, maxChars = 4000) {
  if (prompt.length > maxChars) {
    throw new Error(`Prompt exceeds maximum allowed length of ${maxChars} characters.`);
  }
  return prompt.trim();
}
```

## Production Architecture Takeaway

Validate input length and token budgets at the Cloudflare Worker edge before forwarding any request to an upstream LLM or GPU provider.

✏️ Visual Architecture Diagram

## how this course connects together.

Follow AJ from first principles to production-ready architecture.

Let’s build it!✏️ Visual Diagram: Full-Stack AI Agents in TypeScript (No Python Re…✓ Good PatternVISUAL DIAGRAM[Diagram Walkthrough]Step-by-step diagram breakdown for Full-Stack AI Agents in TypeScript (No Python Required): Agent Evals, Guardrails & Spend Caps in Production: start with Core Architecture & Production Implementation, implement Full-Stack AI Agents in TypeScript (No Python Required), and ship to production.AAA Contrast Verified[Course Outline](/course/full-stack-ai-agents-typescript)

## Full-Stack AI Agents in TypeScript (No Python Required)

5/51

### Core Architecture & Production Implementation

- [1.1Why TypeScript Won the AI Application Layer](/course/full-stack-ai-agents-typescript/lesson/why-typescript-won-the-ai-application-layer)
- [1.2Deterministic Agent Workflows vs. Autonomous Loops](/course/full-stack-ai-agents-typescript/lesson/deterministic-agent-workflows-vs-autonomous-loops)
- [1.3Hybrid Web AI: Routing Between Browser Gemini Nano & Cloud Models](/course/full-stack-ai-agents-typescript/lesson/hybrid-web-ai-routing-browser-gemini-nano-cloud)
- [1.4Serverless GPUs Without Dockerfiles (RunPod Flash)](/course/full-stack-ai-agents-typescript/lesson/serverless-gpus-without-dockerfiles-runpod-flash)
- [1.5Agent Evals, Guardrails & Spend Caps in Production▶](/course/full-stack-ai-agents-typescript/lesson/agent-evals-guardrails-spend-caps-in-production)

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