> For the complete documentation index, see [llms.txt](https://docs.tolvyn.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tolvyn.io/migrate-to-tolvyn/from-helicone.md).

# From Helicone

Two things change: the base URL and your API key. Everything else stays the same.

***

## What changes

|                | Helicone                         | TOLVYN                                       |
| -------------- | -------------------------------- | -------------------------------------------- |
| Base URL       | `https://oai.helicone.ai/v1`     | `https://proxy.tolvyn.io/v1/proxy/openai/v1` |
| API key header | `Helicone-Auth: Bearer hcsk_...` | `Authorization: Bearer tlv_live_...`         |

> **Keep the trailing `/v1`.** Your Helicone base URL ends in `/v1` and so does ours, for the same reason: the OpenAI SDKs append `/chat/completions` to whatever base you give them. An earlier version of this page dropped it, which produced a `404` on the first call after migrating.

Your prompts, models, parameters, and response format are unchanged.

***

## Before / after

### Python (openai SDK)

**Before:**

```python
from openai import OpenAI

client = OpenAI(
    api_key="sk-...",
    base_url="https://oai.helicone.ai/v1",
    default_headers={
        "Helicone-Auth": "Bearer hcsk_...",
        "Helicone-User-Id": "user-123",
    },
)
```

**After:**

```python
from openai import OpenAI

client = OpenAI(
    api_key="tlv_live_...",   # your TOLVYN key
    base_url="https://proxy.tolvyn.io/v1/proxy/openai/v1",
)
```

User attribution works automatically — TOLVYN reads `Helicone-User-Id` if `X-Tolvyn-User` is absent. You can keep the header or remove it.

***

### Node.js (openai SDK)

**Before:**

```js
import OpenAI from "openai";

const client = new OpenAI({
  apiKey: "sk-...",
  baseURL: "https://oai.helicone.ai/v1",
  defaultHeaders: {
    "Helicone-Auth": "Bearer hcsk_...",
    "Helicone-User-Id": "user-123",
  },
});
```

**After:**

```js
import OpenAI from "openai";

const client = new OpenAI({
  apiKey: "tlv_live_...",
  baseURL: "https://proxy.tolvyn.io/v1/proxy/openai/v1",
});
```

***

### curl

**Before:**

```bash
curl https://oai.helicone.ai/v1/chat/completions \
  -H "Authorization: Bearer sk-..." \
  -H "Helicone-Auth: Bearer hcsk_..." \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-4o-mini","messages":[{"role":"user","content":"Hello"}]}'
```

**After:**

```bash
curl https://proxy.tolvyn.io/v1/proxy/openai/v1/chat/completions \
  -H "Authorization: Bearer tlv_live_..." \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-4o-mini","messages":[{"role":"user","content":"Hello"}]}'
```

***

## Header mapping

TOLVYN reads Helicone headers automatically during migration — you don't need to change them immediately.

| Helicone Header       | TOLVYN Equivalent                    | Notes                                 |
| --------------------- | ------------------------------------ | ------------------------------------- |
| `Helicone-Auth`       | `Authorization: Bearer tlv_live_...` | Replace with your TOLVYN key          |
| `Helicone-User-Id`    | `X-Tolvyn-User`                      | Auto-mapped — works without changes   |
| `Helicone-Session-Id` | stored in `tags.helicone_session_id` | Auto-captured                         |
| `Helicone-Property-*` | stored in `tags.helicone_<name>`     | Auto-captured with `helicone_` prefix |

All Helicone headers are stripped before the request reaches OpenAI — they will not appear in provider logs.

***

## Feature comparison

| Feature                                      | Helicone | TOLVYN |
| -------------------------------------------- | -------- | ------ |
| Request logging                              | ✅        | ✅      |
| Cost tracking                                | ✅        | ✅      |
| Per-user attribution                         | ✅        | ✅      |
| Budget enforcement                           | ❌        | ✅      |
| Hard kill switch                             | ❌        | ✅      |
| Tamper-evident audit ledger                  | ❌        | ✅      |
| Per-customer attribution                     | ❌        | ✅      |
| Invoice reconciliation                       | ❌        | ✅      |
| Savings analysis                             | ❌        | ✅      |
| Multi-provider (OpenAI + Anthropic + Google) | ✅        | ✅      |

**On pricing:** Helicone Pro is $79/mo at the time of writing, with basic observability. TOLVYN Growth is ₹17,999/month (approx. $199 USD) with budget enforcement, kill switches, a financial-grade audit trail, per-customer attribution, and invoice reconciliation. If you only need logs, Helicone is cheaper. If you need control, TOLVYN pays for itself the first time a runaway agent gets blocked.

***

## TOLVYN-native headers (optional)

Once migrated, you can adopt TOLVYN's own attribution headers for richer data:

```
X-Tolvyn-Team: backend-team
X-Tolvyn-Service: summarization
X-Tolvyn-Feature: report-gen
X-Tolvyn-Agent: gpt-pipeline
X-Tolvyn-User: user-123
X-Tolvyn-End-Customer: acme-corp
```

These are all optional — use none, some, or all.