Sherlock Calls vs Helicone
Helicone is the open-source AI Gateway and LLM observability platform — one line of code to monitor, debug, and optimize any LLM application across 100+ providers. Sherlock Calls is purpose-built for the operational layer Helicone doesn't reach: investigating production voice calls from Twilio, ElevenLabs, Vapi, and 12+ providers in plain English, from Slack.
TL;DR — The short answer
- 1
Helicone is a lightweight, open-source AI Gateway with one-line LLM observability — ideal for engineering teams who need fast, low-overhead monitoring of LLM application requests across 100+ providers.
- 2
Sherlock Calls is built for voice operations: investigating real production call failures, pulling cross-provider transcripts, and correlating costs and errors across 15+ voice platforms from Slack — zero instrumentation required.
- 3
If your team runs voice AI on Twilio, ElevenLabs, Vapi, or Genesys, Sherlock fills the operational gap Helicone's LLM gateway was never designed to cover.
Understanding both tools
Sherlock Calls
AI-powered voice call investigation
Sherlock Calls is a Slack-native AI investigator purpose-built for voice operations teams. Connect your existing providers — Twilio, ElevenLabs, Vapi, Genesys, and 12 more — and ask questions about your calls in plain English. Sherlock autonomously gathers data across all connected services, correlates events, and delivers a sourced answer in under 5 seconds. No new dashboards. No SDK. No code changes.
- Works inside Slack — no new UI to learn
- Connects to 15+ voice providers in minutes
- Investigates calls autonomously with AI
- Free tier — 100 credits per workspace
Helicone
Build Reliable AI Apps
Helicone is an open-source AI Gateway and LLM observability platform (YC W23) that provides one-line integration for request logging, cost and latency tracking, caching, rate limiting, and session-level debugging across 100+ LLM providers — with self-hosted and cloud deployment options.
- One-line LLM observability: add a single proxy URL change to start logging all requests across OpenAI, Anthropic, Azure, and 100+ providers with zero code instrumentation
- AI Gateway features: intelligent load balancing, automatic failover, built-in caching (reducing API costs 20–30%), and rate limiting across providers
- Session-level tracing: multi-step LLM interaction debugging with token-level cost analysis, prompt version tracking, and user metric monitoring
- Open-source and self-hostable: full deployment control via Docker and Kubernetes Helm charts — no data leaves your infrastructure
Feature comparison — AI Production Observability
Sherlock Calls vs Helicone & peers
All tools in the AI Production Observability category — so you can compare both head-to-head and within the landscape.
| Feature | SherlockCalls | Heliconethis page | Arize AI | Fiddler AI | InfiniteWatch | LangSmith | Noveum AI | Raindrop |
|---|---|---|---|---|---|---|---|---|
| AI call investigation | ||||||||
| AI agent & LLM tracing | ||||||||
| AI governance & compliance | ||||||||
| Offline LLM evaluation | ||||||||
| Provider integrations | 15+ (all voice) | 100+ LLM providers | ~15 (0 voice) | ~10 (0 voice) | ~5 (~2 voice) | Any LLM framework | ~8 (0 voice) | ~8 (0 voice) |
| Cross-provider correlation | ||||||||
| Natural language queries | ||||||||
| Zero-code setup | ||||||||
| Per-call cost tracking | ||||||||
| Free tier available |
Scroll horizontally to compare all tools →
Key differences
Why teams switch from Helicone to Sherlock
Voice Call Investigation vs LLM Request Monitoring
Sherlock Calls
Sherlock investigates specific voice call failures — dropped calls, ElevenLabs latency spikes, Twilio billing anomalies, cross-provider transcript gaps — in plain English from Slack in under 5 seconds. No proxy URL changes. No SDK. No deployment.
Helicone
Helicone monitors LLM API requests at the HTTP proxy layer — logging prompts, completions, token usage, and costs. It is not designed to ingest voice telephony events, correlate call transcripts across providers, or answer operational questions about why a specific Vapi call failed at 3 AM.
Operational Q&A vs Proxy-Layer Request Logs
Sherlock Calls
Ask Sherlock 'Which ElevenLabs voices had the highest latency last week, and which calls did they affect?' in Slack and get a sourced answer correlating your entire voice stack in under 5 seconds.
Helicone
Helicone surfaces LLM request logs, cost dashboards, and latency metrics at the application layer. Answering voice operational questions — specific call outcomes, cross-provider failure correlation, per-call telephony cost — requires data pipelines that route voice events through Helicone, which is not its intended architecture.
Native Voice Integrations vs Proxy URL Routing
Sherlock Calls
Sherlock connects to Twilio, ElevenLabs, Vapi, Retell, Genesys, Amazon Connect, HubSpot, and Datadog via API key — no proxy, no code changes, no deployment. Operational in under 2 minutes.
Helicone
Helicone works by routing LLM API calls through its gateway (a URL change in your application). While extremely lightweight for LLM monitoring, this architecture means telephony events — Twilio call events, ElevenLabs audio metadata, Vapi call outcomes — are not captured unless manually instrumented.
Which tool is right for you?
When to choose Sherlock vs Helicone
Choose Sherlock Calls if…
- Your team operates voice AI in production and needs to investigate specific call failures without adding a proxy layer or writing request instrumentation
- You want cross-provider correlation across Twilio, ElevenLabs, HubSpot, and your CRM with no code changes
- Your operations or support team needs call intelligence in Slack without engineering access to LLM request logs
- You need per-call cost breakdowns and transcript analysis on demand across your voice provider stack
Consider Helicone if…
- Your engineering team needs a lightweight, open-source LLM monitoring layer with one-line integration, built-in caching, load balancing, and the ability to self-host for data residency requirements
- You want to reduce LLM API costs through intelligent caching and routing without adopting a heavyweight observability platform
Pricing
Cost comparison
Sherlock Calls
Free to start
100 credits per Slack workspace. Team plans from $50/month. No credit card required to start.
- Free tier — 100 credits/workspace
- Team: $50–$5,000/month (usage-based)
- Enterprise: custom pricing
- No sales call required to start
- Cancel anytime
Helicone
Free tier — paid plans from $20/month
Helicone offers a free tier with 10,000 requests/month (no credit card required). Paid plans scale with request volume and include advanced features. Self-hosted deployment via Docker/Kubernetes is free with no feature restrictions. Enterprise plans with dedicated support are available via sales.
* Pricing sourced from public information. Contact Helicone for current rates.
FAQ
Frequently asked questions
What is Helicone used for?
Helicone is an open-source AI Gateway and LLM observability platform that logs, monitors, and optimizes LLM API requests across 100+ providers via a one-line proxy URL change. It is designed for engineering teams building LLM applications — not for investigating production voice call failures or operational Q&A from Slack.
Can Helicone investigate voice calls from Twilio or ElevenLabs?
Helicone monitors LLM API requests routed through its gateway — it does not natively ingest Twilio call events, ElevenLabs TTS metadata, or cross-provider voice data. Sherlock Calls provides native integrations with 15+ voice platforms and investigates call failures in plain English from Slack without any proxy routing.
Is Sherlock Calls a Helicone alternative?
They solve different problems. Helicone is right for engineering teams who need lightweight LLM request monitoring, caching, and cost optimization across AI providers. Sherlock Calls is right for voice operations teams who need to investigate production voice calls and get instant answers from their telephony stack — without routing requests through a proxy.
How do I migrate from Helicone to Sherlock Calls?
No migration needed — Sherlock and Helicone serve different layers. If you use Helicone to monitor LLM calls in your voice AI application, Sherlock adds the telephony intelligence layer: call transcripts, cross-provider failure correlation, and per-call cost breakdowns across Twilio, ElevenLabs, and your CRM.
Does Sherlock Calls replace Helicone?
No. Helicone is the right choice for engineering teams who need a lightweight open-source LLM gateway with built-in caching and request logging. Sherlock Calls is the right choice for voice operations teams who need to investigate voice call failures and get instant answers from their provider stack — without a proxy layer or request routing.
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