Cursor vs Unknown Agent

AI Agent Reliability Comparison

According to StupidLLM's incident database of 64 documented AI agent failures, Cursor has 5 incidents (avg severity 6.1/10) while Unknown Agent has 4 (avg severity 8.5/10). Here's how these two AI coding agents compare on reliability, failure modes, and real-world risk.

Cursor

5
Incidents
6.1
Avg Severity
2
Critical
0
High

Top Failure Modes

Security Vulnerability 1
Destructive Action 1
Infinite Loop 1

Worst Incident

STUPID-2026-0029 10/10
Malicious cloned repository triggered code execution in Cursor on Windows

Unknown Agent

4
Incidents
8.5
Avg Severity
3
Critical
0
High

Top Failure Modes

Security Vulnerability 3
Infinite Loop 1

Worst Incident

STUPID-2026-0022 10/10
AI vibe-coded Next.js app pinned vulnerable dependency — cryptominer compromised production server

Comparison Summary

Metric Cursor Unknown Agent
Total Incidents 5 4
Avg Severity 6.1/10 8.5/10
Critical Incidents 2 3
Top Failure Mode Security Vulnerability Security Vulnerability

Frequently Asked Questions

Is Cursor or Unknown Agent more reliable?

Based on StupidLLM's incident database, Cursor has 5 documented failures (avg severity 6.1/10) while Unknown Agent has 4 (avg severity 8.5/10). Cursor shows better reliability based on average severity scores.

What are the main differences between Cursor and Unknown Agent failures?

Cursor's most common failure mode is security vulnerability, while Unknown Agent most commonly fails via security vulnerability. Cursor has 2 critical incidents vs Unknown Agent's 3.

Which has more critical-severity failures?

Unknown Agent has more critical failures (3 vs 2), indicating a higher likelihood of severe, production-impacting incidents.

What is the most dangerous failure mode for Cursor?

Cursor's most frequent failure mode is security vulnerability — its worst documented incident (STUPID-2026-0029) was rated 10/10 severity. Understanding these failure patterns helps teams decide whether Cursor is safe for their specific use case.

What is the most dangerous failure mode for Unknown Agent?

Unknown Agent's most frequent failure mode is security vulnerability — its worst documented incident (STUPID-2026-0022) was rated 10/10 severity. Understanding these failure patterns helps teams decide whether Unknown Agent is safe for their specific use case.

Should I use Cursor or Unknown Agent for production code?

Based on StupidLLM's reliability data, Cursor has a lower average failure severity (6.1/10 vs 8.5/10), making it the statistically safer choice for production environments. However, both agents have documented critical incidents — no AI coding agent is risk-free.

How many verified incidents does each agent have?

Cursor has 5 verified incidents out of 5 total, while Unknown Agent has 4 verified out of 4. Verified incidents are confirmed against source evidence (GitHub PRs, bug reports, news articles), making them the most reliable data points in StupidLLM's database.

How does Cursor compare to other AI agents?

StupidLLM tracks 27 AI coding agents. Cursor has 5 documented failures — placing it in the mid-range for reliability. See the full comparison matrix for context against all tracked agents.

How does Unknown Agent compare to other AI agents?

StupidLLM tracks 27 AI coding agents. Unknown Agent has 4 documented failures — placing it among the higher-risk agents in the database. See the full comparison matrix for context against all tracked agents.