AI & Autonomous Agents•8 min read•2026-10-15
Hardening Function Calling in Desktop AI Agents
Preventing privilege escalation, directory traversal, and command injection when language models trigger system-level function calls.
C
Castov Engineering
Core Platform & DevSecOps Team
Table of Contents
Strict Schema Enforcement with Zod
Every argument emitted by an LLM function call must be parsed through a strict validation schema before being passed to underlying APIs.
import { z } from 'zod';
const SafeFileReadSchema = z.object({
filePath: z.string()
.refine(p => !p.includes('..'), 'Path traversal detected')
.refine(p => p.startsWith('C:\\workspace\\'), 'Outside allowed sandbox')
});Local-First & Zero-Telemetry Computing
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