Best LLM Cost Monitoring Tools in 2026

Top tools for tracking and optimizing LLM API spend across model providers.

We evaluated the leading options for spend firewall in 2026 based on feature depth, pricing transparency, ease of setup, and fit for real-world workflows. Here's our shortlist.

1. sipi.bot

Agent spend firewall

Purpose-built circuit breaker with per-agent caps.

Best for: Teams running autonomous agents

2. Helicone

LLM proxy

Open-source proxy with cost dashboards.

Best for: Self-hosters

3. LangSmith

Tracing

LangChain's tracing and cost platform.

Best for: LangChain teams

4. Portkey

Gateway

Multi-model gateway with cost routing.

Best for: Multi-provider teams

How we evaluated

Each option was assessed on four criteria: (1) depth of features for the specific spend firewall use case, (2) pricing model and transparency, (3) time-to-value and onboarding friction, and (4) real-world usability across team sizes. Options that scored well on breadth but poorly on the specific spend firewall workflow were ranked lower.

Our pick: For most teams, sipi.bot offers the best balance of focus, price, and speed for spend firewall.

Try sipi.bot

Spend firewall for AI agents.

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