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media-generation-skill

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Expert knowledge for AI media generation — image prompting, video workflows, music composition, and TTS best practices

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How to use this skill

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/librefang/librefang/blob/HEAD/crates/librefang-runtime/tests/fixtures/registry/hands/creator/SKILL.md

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Media Generation Expert Knowledge

Tool Reference

image_generate

Generate images from text prompts via OpenAI or MiniMax.

Parameters:

ParameterTypeRequiredDefaultDescription
promptstringyes—Text description of the desired image
providerstringnoautoopenai or minimax
modelstringnoprovider defaultgpt-image-1, dall-e-3, image-01
widthintno1024Image width in pixels
heightintno1024Image height in pixels
countintno1Number of images (1-4)
qualitystringnoautolow, medium, high, auto
seedintnorandomReproducibility seed

Provider-specific notes:

  • OpenAI gpt-image-1: Best for photorealistic and creative images. Supports inpainting hints in prompt. Sizes: 1024x1024, 1792x1024, 1024x1792.
  • OpenAI dall-e-3: Good quality, may revise your prompt (check revised_prompt in response). Only generates 1 image per call.
  • MiniMax image-01: Fast generation, good for illustrations and concept art. Supports arbitrary aspect ratios.

Result: Returns images array with url fields pointing to /api/uploads/{id}.


text_to_speech

Convert text to spoken audio.

Parameters:

ParameterTypeRequiredDefaultDescription
textstringyes—Text to speak (max ~4096 chars per call)
providerstringnoautoopenai or minimax
modelstringnoprovider defaulttts-1, tts-1-hd, speech-2.8-hd
voicestringnoalloyVoice selection (see table below)
speedfloatno1.0Playback speed (0.25 - 4.0)
formatstringnomp3mp3, wav, flac, opus, aac

OpenAI voices:

VoiceCharacter
alloyNeutral, balanced
echoMale, warm
fableStorytelling, expressive
novaFemale, friendly
onyxDeep male, authoritative
shimmerWarm female, gentle

MiniMax voices:

VoiceCharacter
English_Graceful_LadyFemale, elegant
English_Calm_ManMale, composed
English_Energetic_GirlFemale, upbeat

Tips:

  • For long content, split at paragraph boundaries to keep natural pacing
  • tts-1-hd is higher quality but slower; use tts-1 for drafts
  • Speed 0.8-0.9 works well for narration; 1.1-1.2 for summaries

Result: Returns url to the audio file, format, duration_ms, sample_rate.


video_generate

Submit an asynchronous video generation task. Video generation takes 1-3 minutes.

Parameters:

ParameterTypeRequiredDefaultDescription
promptstringyes—Scene description
providerstringnoautoCurrently only minimax
modelstringnoT2V-01Video model
duration_secsintno5Video duration (5-10 seconds)
resolutionstringno1080p720p, 1080p

Prompt writing for video:

  • Be specific about the scene, subject, and action
  • Describe camera movement explicitly: "slow pan left", "zoom in", "static shot"
  • Keep it focused — one scene per generation works best
  • Include lighting and atmosphere: "golden hour lighting", "neon-lit street at night"
  • Avoid complex multi-character interactions (current models handle single subjects best)

Good prompts:

  • "A golden retriever running through a wheat field at sunset, slow motion, cinematic"
  • "Close-up of coffee being poured into a ceramic cup, steam rising, warm morning light"
  • "Aerial drone shot flying over a tropical coastline, turquoise water, white sand beach"

Bad prompts:

  • "A video" (too vague)
  • "Two people having a conversation at a cafe while a dog runs by and a car crashes outside" (too complex)

Result: Returns task_id and provider. You MUST poll with video_status.


video_status

Poll the status of a video generation task.

Parameters:

ParameterTypeRequiredDescription
task_idstringyesFrom video_generate response
providerstringyesMust match the provider from video_generate

Statuses:

StatusMeaningAction
pendingQueued, not startedWait 10-15s, poll again
processingActively generatingWait 15-20s, poll again
completedDoneResult includes file_url
failedGeneration failedCheck error message, may retry with different prompt

Polling pattern:

  1. Call video_generate → get task_id
  2. Wait 10 seconds
  3. Call video_status with task_id + provider
  4. If not completed, wait 15-20 seconds and poll again
  5. Maximum ~10 polls (about 3 minutes total)
  6. Always inform the user of current status

Result (completed): Returns file_url, width, height, duration_secs, provider, model.


music_generate

Generate music from a text prompt and/or lyrics.

Parameters:

ParameterTypeRequiredDefaultDescription
promptstringno*—Style/mood description
lyricsstringno*—Song lyrics with structure
providerstringnoautoCurrently only minimax
modelstringnomusic-2.5Music model
instrumentalboolnofalseGenerate without vocals
formatstringnomp3mp3, wav, flac

*At least one of prompt or lyrics is required.

Prompt writing for music:

For instrumentals, describe:

  • Genre: electronic, jazz, classical, hip-hop, rock, ambient, lo-fi
  • Tempo: slow (60-80 BPM), medium (100-120 BPM), fast (130-160 BPM)
  • Mood: uplifting, melancholic, energetic, relaxing, dramatic, mysterious
  • Instruments: piano, synth, acoustic guitar, strings, drums, bass

For songs with vocals, provide lyrics with structure markers:

[Verse 1]
Walking down the empty street
Moonlight dancing at my feet

[Chorus]
This is where the night begins
Let the music pull us in

[Verse 2]
...

Good prompts:

  • prompt: "Chill lo-fi hip-hop beat, vinyl crackle, mellow piano chords, 85 BPM, rainy day vibe"
  • prompt: "Epic orchestral trailer music, building tension, brass and strings, 140 BPM"
  • prompt + lyrics: "Indie folk acoustic ballad, fingerpicking guitar, gentle male vocals" with lyrics

Result: Returns url to audio file, format, duration_ms, sample_rate.


Combined Workflow Recipes

Podcast Intro

  1. music_generate — instrumental jingle, 10-15 seconds, upbeat
  2. text_to_speech — "Welcome to [show name]..." with energetic voice
  3. Report both URLs to user

Social Media Post

  1. image_generate — eye-catching visual for the post
  2. Suggest caption text based on the image
  3. Optionally text_to_speech for accessibility audio version

Video with Narration

  1. text_to_speech — generate narration audio
  2. video_generate — generate matching video clip
  3. video_status — poll until complete
  4. Report both URLs (user can combine with ffmpeg or editing tools)

Album Art + Preview

  1. image_generate — album cover artwork
  2. music_generate — short preview track matching the artwork mood
  3. Present together

Audiobook Chapter

  1. Split text into sections (~500 words each)
  2. text_to_speech for each section with consistent voice
  3. Report all audio URLs in order

Error Handling

ErrorCauseFix
missing_keyAPI key not configuredAsk user to set OPENAI_API_KEY or MINIMAX_API_KEY
not_supportedProvider doesn't support this modalitySwitch to a provider that does
content_filteredSafety filter rejected the promptRephrase without prohibited content
rate_limitedToo many requestsWait 30-60 seconds and retry
invalid_requestBad parametersCheck parameter ranges (e.g., count 1-4, speed 0.25-4.0)

Provider Capability Matrix

CapabilityOpenAIMiniMax
Image generationgpt-image-1, dall-e-3image-01
Text-to-speechtts-1, tts-1-hdspeech-2.8-hd
Video generation—T2V-01, video-01
Music generation—music-2.5

Auto-detection priority: OpenAI > MiniMax (for capabilities both support). If only MiniMax key is set, all 4 modalities are available through MiniMax.