Alternatives to 42Crunch for LLM cost runaway prevention

What middleBrick covers

  • 18 adversarial probes targeting LLM cost and jailbreak risks
  • OpenAPI 3.0/3.1/Swagger 2.0 parsing with recursive ref resolution
  • Read-only detection with no destructive payloads
  • GitHub Action gating based on score thresholds
  • Continuous monitoring and diff detection across scans
  • Supports PCI-DSS 4.0, SOC 2 Type II, OWASP API Top 10 alignment

Overview of LLM Cost Runaway Risks

LLM applications can generate uncontrolled costs through token overuse, inefficient prompts, and adversarial interactions. Without visibility into prompt flows and model behavior, teams cannot accurately attribute spend or enforce budgets. Detection must focus on prompt patterns that cause repeated generations, oversized responses, and token smuggling attempts that bypass guardrails.

How This Scanner Addresses LLM Cost Runaway

This scanner performs 18 adversarial probes across three scan tiers to surface risks that lead to cost runaway. It focuses on system prompt extraction, instruction override, DAN and roleplay jailbreaks, data exfiltration, cost exploitation, base64 and ROT13 encoding bypass, translation-embedded injection, few-shot poisoning, markdown injection, multi-turn manipulation, indirect prompt injection, token smuggling, tool-abuse, nested instruction injection, and PII extraction.

By probing these vectors, the scanner identifies endpoints or prompts that may trigger excessive token consumption or bypass cost controls. Findings include evidence of techniques such as repeated generation loops, verbose error messages, and prompt chains designed to inflate token usage.

The scanner parses OpenAPI 3.0, 3.1, and Swagger 2.0 specs with recursive $ref resolution and cross-references spec definitions against runtime behavior. This highlights undefined security schemes, deprecated operations, and missing pagination that can contribute to unthrottled request volume.

Detection Scope and Limitations

The scanner is a read-only assessment tool. It does not execute destructive payloads, perform active SQL or command injection, or attempt to remediate findings.

  • It does not detect business logic vulnerabilities that require deep domain understanding.
  • It does not detect blind SSRF that relies on out-of-band infrastructure.
  • It does not replace a human pentester for high-stakes audits.

These limitations are important for cost-related assessments; techniques that drive token consumption may be influenced by application logic that the scanner cannot infer. Use the findings as evidence for deeper manual review where cost controls are critical.

Integration into Development Workflow

Integrate scanning into your CI/CD and deployment pipelines to catch cost-risk patterns before they reach production. The CLI supports scripted execution and JSON output for automated analysis. The GitHub Action can gate merges when the scan score drops below a defined quality threshold.

middlebrick scan https://api.example.com/openapi.json --output json

For deployed services, scheduled rescans can track how prompt changes affect token usage over time. Diff detection across scans surfaces new findings, resolved findings, and score drift, helping teams correlate configuration changes with cost anomalies.

Product Options and Compliance Alignment

Choose a tier that matches your API inventory and monitoring needs.

  • Free: 3 scans per month with CLI access.
  • Starter: 15 APIs, monthly scans, dashboard, email alerts, MCP Server.
  • Pro: 100 APIs with incremental add-ons, continuous monitoring, GitHub Action gates, CI/CD integration, Slack/Teams alerts, compliance reports, signed webhooks.
  • Enterprise: unlimited APIs, custom rules, SSO, audit logs, SLA, dedicated support.

Findings map to three frameworks: PCI-DSS 4.0, SOC 2 Type II, and OWASP API Top 10 (2023). For other frameworks, this scanner helps you prepare for and supports audit evidence aligned with security controls described in relevant guidelines.

Frequently Asked Questions

Can this scanner prevent LLM cost runaway on its own?
No. The scanner detects risky patterns and provides remediation guidance but does not fix, patch, or block runtime behavior.
Does scanning consume significant API quota or incur costs on my behalf?
The scanner uses read-only methods and text-only POST for LLM probes. It is designed to avoid heavy payloads that would inflate token usage during assessments.
How are sensitive findings handled during scans?
Customer scan data is deletable on demand and purged within 30 days of cancellation. Data is never sold and is not used for model training.
Can authenticated scans be used in CI/CD?
Yes. Authenticated scanning is available from Starter tier onward, with domain verification and a header allowlist to control which credentials are forwarded.