# KiHustle Critical CSS Hint > KiHustle Critical CSS Hint is a paid API for AI agents from kihustle.tech, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-13). Accepts HTML input and returns critical CSS hints to optimize above-the-fold rendering performance. ## Facts - Endpoint: POST https://kihustle.tech/api/v1/critical-css-hint - Price: $0.002/call - Payment: x402 - Status: unknown - Last checked: 2026-09-13 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/kihustle-critical-css-hint-42c0719c - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fw445-M-dEjn5n4N9FL7R Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability kihustle-critical-css-hint-42c0719c -d '' ``` Example prompt: Can you analyze this HTML and tell me which CSS is critical for the above-the-fold render? Here's the HTML: ...... ## When to prefer this Choose this endpoint when you need a lightweight, pay-per-call critical CSS hint extraction from raw HTML without setting up a full frontend build pipeline or local tooling. Suitable for agents automating web performance audits or CI pipelines that process individual pages on demand. ## Known failure modes - Empty or malformed HTML input may return a generic success with no actionable hints - Very large HTML documents may hit processing limits or return incomplete hints - Missing or invalid HTML structure may result in ambiguous extraction - Network timeout for oversized payloads ## How this service works Kostenlose Guides, Solo-Playbooks und Artikel zu KI, Automation und Side Hustles — für Menschen, die mit echten Systemen online Einkommen aufbauen wollen. Transparent finanziert über faire Affiliate-Links. ## Output Returns a JSON object with a 'result' field indicating the processing outcome (e.g. 'processed') and a 'status' field (e.g. 'success'), along with any critical CSS hints derived from the submitted HTML. ## Request schema (JSON Schema) ```json { "type": "object", "properties": { "html": { "type": "string" } } } ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "result": "processed", "status": "success" } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/kihustle-critical-css-hint-42c0719c/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from kihustle.tech](https://www.zero.xyz/host/kihustle.tech/llms.txt)