Troubleshooting

HTTP 401 — Authentication Failed

What it means: The server couldn't validate your API key. This happens when the key is absent, malformed, or has been deleted.

How to fix it:

Confirm the Authorization header is present and spelled correctly
Make sure there is no extra whitespace around the key value
If the key may have been deleted or rotated, generate a new one at revomail.io/keys

# The header must look exactly like this
-H "Authorization: Bearer sk-llmaai-your-key-here"

HTTP 402 — Account Balance Depleted

What it means: Your prepaid credit has run out. The API will block all requests until you reload.

How to fix it: Add credit at revomail.io/billing. Requests resume working immediately — there is no waiting period after a top-up.

HTTP 404 — Model Not Recognized

What it means: The value in your model field doesn't match any model the API knows about.

How to fix it: Copy the slug exactly from the Models reference. Slugs are case-sensitive — lowercase only.

// Wrong — uppercase
{ "model": "GPT-5.4" }

// Correct — lowercase slug from the docs
{ "model": "gpt-5.4" }

HTTP 400 — Invalid Request

What it means: The request body is malformed, missing a required field, or contains an out-of-range value.

Common causes:

messages array is absent or empty
temperature is set outside the 0–2 range
A message object is missing role or content
JSON is syntactically invalid (unclosed braces, trailing commas)

How to fix it: Validate your payload against the API Reference.

HTTP 429 — Rate Limit Hit

What it means: You are sending requests faster than the server allows.

How to fix it: Slow down your request rate and implement exponential backoff:

import time

def call_with_backoff(client, **kwargs):
    delay = 1
    for attempt in range(6):
        try:
            return client.chat.completions.create(**kwargs)
        except Exception as exc:
            if "429" not in str(exc):
                raise
            time.sleep(delay)
            delay *= 2
    raise RuntimeError("Gave up after repeated rate limit errors")

Streaming Responses Not Arriving

What it means: You set stream: true but your client isn't reading the SSE stream correctly.

How to fix it: Use a streaming-aware HTTP client or the OpenAI SDK's streaming helper:

stream = client.chat.completions.create(
    model="glm-5-turbo",
    messages=[{"role": "user", "content": "Tell me a short story."}],
    stream=True,
)
for chunk in stream:
    text = chunk.choices[0].delta.content
    if text:
        print(text, end="", flush=True)

Output Gets Cut Off

What it means: The model stopped generating because it hit the max_tokens limit you set (or the model's built-in limit).

How to fix it: Raise max_tokens or remove the parameter to let the model use its full default limit.

If a model is temporarily down, Revo Mail's circuit breaker will automatically route around failing channels. You can also configure fallback chains to redirect traffic to a backup model of your choice.

Go to Console → Key Management
Click Fallback Rules on the relevant API key
Add a fallback: e.g., if gpt-5.4 is unavailable → try claude-sonnet-4.5

See Advanced Features for details.

To get notified when a model goes down, enable Model Unavailable alerts in Account Settings → Alerts.

Still Stuck?

If none of the above resolves your problem, reach out via the community or the console:

Telegram community: Join us on Telegram — fastest way to get help from the team and other users
Discord community: Join us on Discord — chat with the team and other developers
Console: revomail.io
Contact form: revomail.io/contact

When writing in, please include the complete error response body, the model slug you were targeting, and the approximate time of the failed request. This speeds up diagnosis significantly.