Sutrace vs Helicone: gateway visibility plus the eval and budget layer Helicone doesn't ship

TL;DR. Helicone is the fastest setup in the LLM-observability category — change one base URL, and your traces appear. That's a real advantage. The trade-off is depth: the eval tooling is the weakest in the category, the budget controls are observation-only, and the proxy adds a hop to your latency budget. Helicone Pro is $20/seat/mo with a $200/mo cap — generous for what it does. Sutrace is more work to set up (an OTel collector instead of a base-URL flip) but you get hard budget caps, on-host prompt redaction, real eval primitives, prompt-injection detection, and one dashboard for AI agents alongside the rest of your stack. EU residency by default. If you're shipping agents in 2026 and prompt injection has shifted from "interesting" to "I have a CISO" — see the EchoLeak/CamoLeak post — the proxy-only model has gaps. This page is the honest version.

What Helicone gets right

I want to be careful here because Helicone is a good product. The category has a lot of vendors who are precious about their architecture; Helicone isn't, and the team has shipped consistently.

1. The fastest setup in the category. Change OPENAI_BASE_URL to https://oai.helicone.ai/v1 and add a header. That's it. No SDK, no decorators, no collector. For teams who want telemetry today without an engineering project, this matters.

2. Caching as a first-class feature. The proxy model lets Helicone cache responses transparently. For teams hitting the same prompt repeatedly — RAG pre-warmers, agent test loops, batch eval runs — the cache pays for itself in API spend.

3. Generous pricing at the seat tier. Helicone Pro at $20/seat/mo with a $200/mo cap is the lowest-friction Pro tier in the category. The cap is the unusual part — most competitors charge unbounded.

4. The "Complete Guide" content is honest. Helicone publishes a comprehensive competitor guide that covers their own gaps. That's rare in marketing.

5. Open-source self-host path. The Helicone gateway is OSS. If you don't want a third party in your traffic path, you can run it yourself.

If you want a basic dashboard, fast caching, and a $20/seat bill — Helicone is the answer. Stop reading.

What's harder in Helicone

The proxy-first architecture is a real design choice with real consequences.

1. Evals are the weakest in the category

The honest read is from Soufian Azzaoui's DEV writeup of trying all four: "Helicone's evals feel like an afterthought." LangSmith, Langfuse, and Phoenix all ship dataset primitives, LLM-as-judge runners, and regression tracking that Helicone tacks on later. If you do serious eval work, you'll outgrow Helicone's eval tooling fast. Hamel Husain's eval FAQ — see our post on his commodification thesis — argues prefab evals are the wrong primitive in the first place. Either way, Helicone's eval surface is the smallest.

2. Budget control is observation, not enforcement

Helicone shows you what an agent is spending. It does not stop the agent from spending more. When a stuck loop hits — see the RelayPlane runaway $0.80→$47 case — you find out in the dashboard, not at the next request. The window between "first runaway request" and "you notice in the dashboard" is where the money goes. Sutrace's budget interlock fires synchronously: the next provider call is blocked at the SDK or proxy layer the moment the running total crosses the threshold.

3. Proxy hop adds latency

Every request goes through Helicone's edge. They've optimised hard — usually 10–30ms p50 — but it's not free. If your agent makes 50 sequential provider calls per run, that's 500–1,500ms added to wall-clock time. For real-time agents, this matters. Sutrace's SDK middleware is in-process and adds <1ms p99.

4. Limited unification

Helicone observes LLMs. That's the scope. If you also have hardware (SCADA), software services, web/APIs, or a Datadog bill that's eating you alive (see the Datadog comparison) — that's a separate tool. Sutrace is one dashboard for all of it.

5. Limited multi-provider routing visibility

Helicone is provider-aware (OpenAI, Anthropic, etc.) but the gateway routing visibility — "this OpenRouter request actually hit Anthropic, not OpenAI" — is shallow. See the multi-provider routing post.

When Helicone wins

Be honest with yourself. Pick Helicone if:

• You want telemetry running by end of day with zero engineering investment.
• Your team's only need is "show me a dashboard of LLM calls and costs."
• You hit the $200/mo Pro cap before any other vendor's tier catches up — Helicone's cap is the cheapest Pro in the category.
• You want prompt caching as a first-class proxy feature.
• You're a US team with no EU-residency obligation. Helicone is US-resident by default.
• You're allergic to running an OTel collector and prefer base-URL flips.

When Sutrace wins

• You need budget caps that stop runaways, not log them.
• You're shipping agents that touch untrusted inputs (customer messages, emails, web pages, PDFs) and prompt injection is on your threat model.
• You're EU-resident or selling into EU and your DPO has flagged US-default tooling.
• You have hardware/PLC, software services, or web/APIs in the same stack and want one dashboard.
• You use OpenRouter or AWS Bedrock and need to see the upstream provider that actually served each request.
• You're doing serious eval work — LLM-as-judge with versioned prompts, regression tracking against baselines.
• Your latency budget can't tolerate a proxy hop.
• You're hitting the limits of "observation only" and need enforcement.

Side-by-side comparison

The "gateway + eval" hybrid pattern

The trend across teams who've tried both: keep Helicone (or any gateway) for the cheap proxy benefits — caching, base-URL routing, request logging — and add a deeper observability layer for evals and enforcement. We covered this in the 4-way honest comparison post. Sutrace fits the deeper layer: you can run Helicone in front and Sutrace in the SDK middleware. The OTel spans capture both legs.

If you're already at this hybrid stage, you have two stacks to budget for. Most teams eventually consolidate on whichever side does more — and the deeper-layer side wins, because gateways are commoditised and evals + enforcement are not.

Migration playbook

Most teams don't fully migrate off Helicone — they layer Sutrace on top, then quietly let the Helicone subscription lapse if it's no longer pulling weight.

Path A: Replace Helicone entirely.

1. Remove the OPENAI_BASE_URL override and Helicone auth header.
2. Install the Sutrace SDK in your provider client (one line for OpenAI/Anthropic/Bedrock/OpenRouter).
3. Set a budget cap.
4. Done. Cancel Helicone at next renewal.

Path B: Run both.

1. Keep Helicone for caching.
2. Add Sutrace SDK for budget caps, redaction, evals, prompt-injection signals.
3. Verify the OTel spans capture both legs (gateway and upstream provider).
4. Decide later whether the cache value justifies the second subscription.

Most teams take Path A within 2–3 months. The cache is real but rarely the deciding cost driver.

Frequently asked questions

Why is Helicone faster to set up?

Because it's a proxy. Change one URL, you're done. Sutrace requires installing an SDK or running an OTel collector. The trade-off: the proxy adds a hop to every request, and the proxy can't see in-process state (variable values, decision branches in your agent code) the way an SDK can.

What's the real Helicone cost at scale?

Helicone Pro at $20/seat/mo with a $200/mo cap is the headline. Above that, you're in custom pricing. The cap is the unusual feature — most competitors are unbounded. For a 10-seat team running 1M requests/mo, Helicone is roughly $200/mo all-in. Sutrace at the same scale is roughly $150–$400 depending on payload size.

Does Sutrace replace the Helicone proxy entirely?

If you want it to. Our SDK middleware sits in-process and is functionally a "local proxy" without the network hop. If you specifically want the proxy architecture (for centralised request logging, for caching, for routing without code changes), we offer a proxy mode too. But most teams move to the SDK and don't miss the proxy.

Can I keep Helicone caching and use Sutrace for everything else?

Yes. Run Helicone in front (cache + base-URL routing) and Sutrace SDK behind (budgets, redaction, evals, injection signals). The OTel spans tag both legs. This works fine; it's just two bills.

Is Helicone OSS?

The gateway is. The cloud product (UI, billing, multi-tenant) is closed. If self-host is a hard requirement, Helicone OSS or Langfuse are the honest options.

How does Sutrace's eval tooling compare?

Datasets, LLM-as-judge runners, regression tracking against baselines, custom evaluator functions. Helicone has dataset primitives but the runner and regression-tracking surface is shallow. If your eval workflow is "I ran a dataset against three prompt versions and need to see which regressed" — Sutrace is the better fit. See the Hamel Husain post for the deeper view on eval philosophy.

What about the latency overhead?

Helicone proxy: 10–30ms p50 added per request, sometimes more on cold edges. Sutrace SDK: <1ms p99, because we don't add a network hop. For an agent with 50 sequential calls per run, that's 500–1,500ms versus <50ms wall-clock difference.

Does Sutrace support EU residency?

Default. europe-west3 (Frankfurt). No US replication. DPA here.

Get started

Self-serve. Drop the SDK in your provider client, set a budget cap, and the dashboard fills in within minutes. No sales call. Pricing here. For the broader picture see the AI agent observability use case.