Sherlock Calls vs Braintrust
Braintrust is the evaluation infrastructure powering engineering teams at Notion, Stripe, and Vercel. Sherlock Calls is built for the operations teams who run voice AI in production — no eval pipelines, just answers in Slack.
TL;DR — The short answer
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Braintrust is a best-in-class LLM evaluation platform — purpose-built for AI engineering teams who need rigorous prompt testing, regression detection, and production tracing.
- 2
Sherlock Calls is purpose-built for voice operations — investigating real calls, pulling transcripts, and correlating failures across 15+ providers from Slack.
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If your team builds AI models, Braintrust is essential. If your team operates voice AI in production, Sherlock fills the gap Braintrust doesn't 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
Braintrust
The AI evaluation and observability platform for building quality AI products
Braintrust is a managed LLM evaluation and observability platform that helps AI engineering teams run experiments, detect regressions, and monitor production traces at scale.
- Run LLM evaluations against real datasets with side-by-side prompt comparison and automated CI regression detection
- Monitor production traces, tool calls, latency, and cost with Brainstore — a custom database delivering 86× faster full-text search than generic alternatives
- Loop: AI-powered prompt optimization that automatically generates better prompts, scoring criteria, and datasets
- Trusted by AI engineering teams at Notion, Stripe, Vercel, Airtable, Instacart, and Zapier
Feature comparison — LLM Eval & Benchmarking
Sherlock Calls vs Braintrust & peers
All tools in the LLM Eval & Benchmarking category — so you can compare both head-to-head and within the landscape.
| Feature | SherlockCalls | Braintrustthis page | Galileo | Maxim |
|---|---|---|---|---|
| AI call investigation | ||||
| AI agent & LLM tracing | ||||
| AI governance & compliance | ||||
| Offline LLM evaluation | ||||
| Provider integrations | 15+ (all voice) | ~15 (0 voice) | ~10 (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 Braintrust to Sherlock
Production Call Investigation vs Evaluation Pipelines
Sherlock Calls
Sherlock investigates real production calls — who called, what was said, why it failed, what it cost — directly from Slack with no setup beyond connecting your provider API keys.
Braintrust
Braintrust excels at structured evaluation workflows: comparing prompts, detecting regressions in CI, and scoring LLM outputs at scale. It is not designed for real-time voice call investigation or operational Q&A.
Native Voice Integrations vs Framework-Agnostic Logging
Sherlock Calls
Sherlock speaks the language of voice: DTMF events, latency spikes, transcript sentiment, per-minute billing, and cross-provider call correlation — connected out of the box, with no instrumentation.
Braintrust
Braintrust ingests trace data from any LLM application but has no native connectors for Twilio, ElevenLabs, Vapi, or Genesys. Integrating voice call data would require custom SDK instrumentation.
Built for Operations Teams, Not Just Engineers
Sherlock Calls
Sherlock is designed for the whole team — operations managers, support leads, and engineers alike can ask questions in natural language and get answers without writing queries or reading logs.
Braintrust
Braintrust is primarily an engineering-layer tool. Its power is in structured evaluation workflows that require technical setup and interpretation — it is not designed for operational Q&A by non-engineering users.
Which tool is right for you?
When to choose Sherlock vs Braintrust
Choose Sherlock Calls if…
- Your team operates voice AI in production and needs to investigate specific call failures
- You want cross-provider correlation across Twilio, ElevenLabs, HubSpot, and Datadog without writing code
- Your operations or support team needs call intelligence in Slack without engineering involvement
- You need per-call cost breakdowns and transcript analysis on demand
Consider Braintrust if…
- Your team is actively building and iterating on LLM applications and needs rigorous eval infrastructure
- You need prompt regression testing integrated into your CI/CD pipeline
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
Braintrust
Free / $249/month (Pro)
Braintrust offers a generous free tier (1M trace spans, 14-day retention). The Pro plan at $249/month includes 5GB storage and 30-day retention. Enterprise pricing is custom.
* Pricing sourced from public information. Contact Braintrust for current rates.
FAQ
Frequently asked questions
What is the difference between Sherlock Calls and Braintrust?
Sherlock Calls investigates real voice production calls in plain English from Slack — pulling transcripts, costs, and failure details from providers like Twilio and ElevenLabs instantly. Braintrust is an LLM evaluation platform for AI engineering teams, focused on prompt testing, regression detection, and production trace monitoring. They serve fundamentally different teams.
Can Braintrust investigate voice calls from Twilio or ElevenLabs?
Braintrust does not have native integrations with Twilio, ElevenLabs, Vapi, or other voice providers. It ingests LLM trace data via SDK instrumentation. Sherlock Calls supports 15+ voice and telephony platforms natively, with no code changes required.
Is Sherlock Calls a Braintrust alternative?
They solve different problems for different teams. Braintrust is the right choice for AI engineering teams building and improving LLM applications. Sherlock Calls is the right choice for voice operations teams who need to investigate production calls. Many teams benefit from having both.
How do I migrate from Braintrust to Sherlock Calls?
No migration needed — Braintrust and Sherlock serve different teams with different workflows. Connect Sherlock to your Slack workspace and your voice provider API keys in under 2 minutes. Your Braintrust evaluation pipelines continue unchanged for your engineering team.
Does Sherlock Calls replace Braintrust?
No. Braintrust is the right platform for teams who need rigorous LLM evaluation, prompt regression testing, and AI model benchmarking. Sherlock Calls is the right platform for voice operations teams who need to investigate live calls and get instant answers from their telephony stack. Many teams run both.
Ready to investigate your calls the smarter way?
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