Seedance 2.0 Error Guide: Every Error Explained with Fixes

Seedance 2.0 (and its faster sibling, Seedance 2.0 Fast) are among the most capable video generation models available today. But if you've been working with the API, you've likely hit some errors that aren't immediately obvious to debug.

We've been running both models heavily and have seen just about every error they can throw. This guide documents every error we've encountered, explains what causes it, and gives you the exact fix.

Quick Reference Table

Content Moderation Errors

Content moderation errors are the most common category of failures. These are triggered by ByteDance's content safety filters, which scan both inputs and generated outputs. The important thing to know: you are not charged for failed generations.

Output Video Sensitive Content

The request failed because the output video may contain sensitive information.

OutputVideoSensitiveContentDetected: The request failed because the output video may contain sensitive information.

This is the single most common error. The video was generated but ByteDance's post-generation content filter flagged it. This happens even with seemingly innocent prompts — the model may generate intermediate frames that trigger the filter even if your prompt is clean.

How to fix it:

• Rephrase your prompt to be more specific and less ambiguous
• Avoid language that could be interpreted as violent, sexual, or politically sensitive
• Retry the exact same prompt — results vary between runs due to randomness in generation
• If a prompt consistently fails, try breaking it into simpler descriptions

Output Audio Sensitive Content

The request failed because the output audio may contain sensitive information.

OutputAudioSensitiveContentDetected: The request failed because the output audio may contain sensitive information.

Same concept as above, but the audio track was flagged. This is especially common with dialogue-heavy prompts or anything that might produce speech resembling copyrighted music or real people's voices.

How to fix it:

The simplest fix — if you don't need audio — is to disable it entirely:

import requests

response = requests.post(
    "https://api.segmind.com/v1/seedance-2.0",
    headers={"x-api-key": "YOUR_API_KEY"},
    json={
        "prompt": "A cat walking through a garden",
        "duration": 5,
        "resolution": "720p",
        "generate_audio": False  # Disables audio generation entirely
    }
)

If you do need audio, rephrase any dialogue in your prompt and avoid references to specific songs, artists, or well-known catchphrases.

Copyright Policy Violation

OutputVideoSensitiveContentDetected.PolicyViolation: The request failed because the output video may be related to copyright restrictions.

A more specific variant of the content moderation error — the generated video contained recognizable copyrighted material.

How to fix it: Don't reference specific copyrighted characters (e.g., "Mickey Mouse"), brand logos, or intellectual property in your prompts. Use generic descriptions instead: "a cartoon mouse" rather than the specific character name.

Input Image Contains Real Person

ByteDance video API error: The request failed because the input image may contain real person.

ByteDance blocks image-to-video generation when the input image contains identifiable real human faces. This is a hard block — no amount of rephrasing will fix it.

How to fix it:

• Use illustrated, stylized, or AI-generated character images instead of real photos
• Crop or blur faces in your reference images before uploading
• For product shots or scenes, ensure no identifiable faces are visible

Input Text Sensitive

ByteDance video API error: The request failed because the input text may contain sensitive information.

Your prompt text itself was flagged before generation even started. This catches violent, political, adult, or otherwise restricted language.

How to fix it: Review your prompt for any language that could be interpreted as violent, politically sensitive, or adult in nature. Rewrite using neutral, descriptive language.

Parameter Validation Errors

Parameter validation errors are the most preventable category of failures. They're also among the most frequent — they're caused by invalid API parameters and can be caught client-side before making a request.

first_frame + reference_images Conflict

first_frame/last_frame mode is mutually exclusive with reference_images.

ByteDance video API error: The parameter 'content' specified in the request is not valid: first/last frame content cannot be mixed with reference media content.

Seedance 2.0 has two distinct modes for visual input, and they cannot be combined:

Mode 1: Frame-guided generation — You provide start/end frames and the model generates video between them.

# ✅ Correct: Frame mode
response = requests.post(
    "https://api.segmind.com/v1/seedance-2.0",
    headers={"x-api-key": "YOUR_API_KEY"},
    json={
        "prompt": "A flower blooming in timelapse",
        "first_frame_url": "https://example.com/flower-bud.jpg",
        "last_frame_url": "https://example.com/flower-bloom.jpg",
        "duration": 5,
        "resolution": "720p"
    }
)

Mode 2: Reference-guided generation — You provide reference images/videos/audio as style or content guidance.

# ✅ Correct: Reference mode
response = requests.post(
    "https://api.segmind.com/v1/seedance-2.0",
    headers={"x-api-key": "YOUR_API_KEY"},
    json={
        "prompt": "A character dancing in a park",
        "reference_images": ["https://example.com/character.jpg"],
        "duration": 5,
        "resolution": "720p"
    }
)

# ❌ Wrong: Mixing both modes
response = requests.post(
    "https://api.segmind.com/v1/seedance-2.0",
    headers={"x-api-key": "YOUR_API_KEY"},
    json={
        "prompt": "A character dancing",
        "first_frame_url": "https://example.com/start.jpg",    # Frame mode
        "reference_images": ["https://example.com/char.jpg"],   # Reference mode
        "duration": 5
    }
)
# This WILL fail with the conflict error

last_frame Requires first_frame

last_frame_url requires first_frame_url to be provided.

You can use first_frame_url alone, but last_frame_url always requires first_frame_url to also be set. Think of it as: you can define where the video starts, or where it starts AND ends, but not only where it ends.

Prompt Required

Prompt is required for video generation.

Every Seedance 2.0 request needs a prompt field with a non-empty string. Even when using frame or reference modes, you must describe what you want the video to contain.

Invalid Duration

the parameter duration specified in the request is not valid

invalid video duration, exceeds 15s

Duration only accepts specific discrete values — not arbitrary numbers.

Valid durations: 4, 5, 6, 8, 10, 12, 15

Notably: 7, 9, 11, 13, 14 are all invalid. And the maximum is 15 seconds.

Invalid Resolution

the parameter resolution specified in the request is not valid

Valid resolutions: "480p" or "720p" only. There is no 1080p support at this time.

reference_audio Cannot Be the Only Reference

reference_audio cannot be the only reference input.

If you're using reference_audios, you must also provide at least one reference_images or reference_videos. Audio alone isn't enough context for the model to generate video.

Image URL Download Failed

The parameter 'content[1].image_url' specified in the request is not valid: resource download failed.

ByteDance's servers couldn't download your image URL. Common causes: the URL requires authentication, the pre-signed URL expired, the server is geo-restricted, or the URL simply returns a 404.

How to fix it: Ensure all image/video URLs are publicly accessible without authentication. Test them in an incognito browser window first. If using pre-signed URLs, make sure they have sufficient expiry time (at least 10 minutes).

Infrastructure & Transient Errors

Infrastructure errors are less frequent but important to handle. These are mostly transient and can be handled with proper retry logic.

Silent Failures — Empty 200 Response

This is the trickiest error because there is no error message. The API returns HTTP 200 but the response body is empty — no video URL, no error, nothing.

How to detect and handle it:

response = requests.post(url, headers=headers, json=payload)

if response.status_code == 200:
    data = response.json() if response.text.strip() else None

    if not data or not data.get("output_url"):
        # Silent failure — retry
        print("Empty response received, retrying...")
        time.sleep(10)
        response = requests.post(url, headers=headers, json=payload)
    else:
        video_url = data["output_url"]
        print(f"Video ready: {video_url}")

Polling Timeout

Video generation polling timed out.

Longer videos (10-15 seconds) can take 3-5 minutes to generate. If your client timeout is set too low, you'll get this error even though the video may still be generating on the backend.

How to fix it: Set your HTTP client timeout to at least 5 minutes. If you're using the async/polling approach, increase your maximum poll count. Generation tends to be slower during peak hours.

Internal Service Error

The service encountered an unexpected internal error.

A transient error on ByteDance's side. Nothing wrong with your request — just retry.

SSL/TLS Error

SSLError [SSL: TLSV1_ALERT_INTERNAL_ERROR]

Transient TLS handshake failure. Retry automatically — this resolves on its own.

Stale Request

[STALE_REQUEST_MARKED_FAILED_BY_BACKGROUND_CLEANUP]

Your request sat in the processing queue too long and was cleaned up. This typically happens during high-traffic periods. Just retry.

Missing SDK Dependency (resolved)

No module named 'byteplussdkcore'

This was a Segmind infrastructure issue where a required SDK dependency was temporarily missing on our servers. This has been resolved. If you encountered this error previously, it should no longer occur. If you see it again, please contact our support team.

Recommended Retry Logic

A meaningful portion of errors are transient infrastructure issues (and content moderation errors are also worth retrying with rephrased prompts), so you should build retry logic into any production integration:

import requests
import time

def generate_video(payload, api_key, max_retries=3):
    """Generate a video with automatic retry for transient errors."""
    url = "https://api.segmind.com/v1/seedance-2.0"
    headers = {"x-api-key": api_key}

    retryable_patterns = [
        "internal error",
        "SSLError",
        "STALE_REQUEST",
        "polling timed out",
    ]

    for attempt in range(max_retries):
        try:
            response = requests.post(
                url, headers=headers, json=payload, timeout=300
            )

            # Handle silent failures (empty 200)
            if response.status_code == 200:
                if not response.text.strip():
                    print(f"Attempt {attempt + 1}: Empty response, retrying...")
                    time.sleep(10 * (attempt + 1))
                    continue

                data = response.json()
                if data.get("output_url"):
                    return data  # Success

            # Check if error is retryable
            error_msg = response.text.lower()
            if any(p.lower() in error_msg for p in retryable_patterns):
                wait = (2 ** attempt) * 5  # 5s, 10s, 20s
                print(f"Attempt {attempt + 1}: Transient error, retrying in {wait}s...")
                time.sleep(wait)
                continue

            # Non-retryable error — return as-is
            return {"error": response.text, "status_code": response.status_code}

        except requests.exceptions.Timeout:
            print(f"Attempt {attempt + 1}: Request timed out, retrying...")
            time.sleep(10 * (attempt + 1))
            continue
        except requests.exceptions.SSLError:
            print(f"Attempt {attempt + 1}: SSL error, retrying...")
            time.sleep(5)
            continue

    return {"error": "Max retries exceeded", "attempts": max_retries}


# Usage
result = generate_video(
    payload={
        "prompt": "A drone shot over a mountain lake at sunrise",
        "duration": 5,
        "resolution": "720p",
        "generate_audio": False,
    },
    api_key="YOUR_API_KEY"
)
print(result)

Best Practices

Validate parameters client-side before sending. A large share of failures are bad parameters — check duration values, resolution strings, and mode conflicts before making the API call.

Implement retry with exponential backoff. Use the retry pattern above for all production integrations. Transient errors are common with any video generation API.

Set generate_audio: false when you don't need audio. This eliminates a significant chunk of content moderation failures. If you're adding your own soundtrack or the video doesn't need sound, always disable audio generation.

Keep reference URLs publicly accessible. Pre-signed URLs should have at least 10 minutes of validity. Test URLs in an incognito browser before passing them to the API.

Don't mix first_frame and reference modes. This is a hard constraint in the API — choose one approach per request.

Budget for retry overhead in cost estimates. Plan for retries in your cost model. Remember: failed generations are not charged.

Set generous timeouts. Video generation can take 3-5 minutes for longer durations. Set your HTTP client timeout to at least 300 seconds.

Resources

For more details, check out these resources:

• Seedance 2.0 Model Page
• Seedance 2.0 Fast Model Page
• Segmind API Documentation

If you're still hitting errors not covered here, reach out to us on Discord or email support@segmind.com. We're happy to help debug.