image-edit
Use this skill for all image editing and enhancement requests on Starchild.
Covers: general editing, background replacement, super-resolution, old photo restoration, colorization, person removal, portrait retouching (skin smoothing, blemish removal, teeth whitening), slimming, color grading, artistic filters, image blending, outpainting, local editing, text rendering, multi-angle generation, before/after comparison, car recoloring, car wrap preview, and fitness/medical transformation comparisons.
Core principle: call the provided script. Do not re-implement proxy/billing plumbing.
When to use image-edit vs other image skills:
- image-edit → user wants to EDIT, ENHANCE, or TRANSFORM an existing image
- image-portrait → user wants a portrait with their face/identity preserved from a reference photo
- image-create → user wants to CREATE something from a text description (no source image)
---
1. Quick start — basic edit (most common)
exec(open('skills/image-edit/edit_image.py').read())
result = edit_image(
image_path="uploads/photo.jpg",
prompt="make the sky more dramatic with golden sunset colors",
action="enhance",
)
# result -> {"success": True, "images": [{"local_path": "output/images/..."}], ...}
The script reads the local file, base64-encodes it, and sends it to fal.ai as a data URI — no manual URL publishing needed.
2. Quick start — public URL
exec(open('skills/image-edit/edit_image.py').read())
result = edit_image(
image_url="https://example.com/photo.jpg",
prompt="replace the background with a tropical beach",
action="replace_bg",
)
Delivering the result to the user — IMPORTANT
Never hand the user the raw fal.media URL. fal serves files with restrictive CSP headers. The only reliable delivery path is the already-downloaded local file:
- Use each image's
local_path(e.g.output/images/xxx.png) — the script always downloads on success. - Tell the user the files are saved to
output/images/and viewable in the workspace file panel. - On Web channel, embed inline so the user can preview in chat:

- On Telegram / WeChat: send via
send_to_telegram(file_path="output/images/...", message_type="image")orsend_to_wechat(file_path="output/images/...", message_type="image").
---
3. Parameters
| Parameter | Required | Default | Description |
|---|---|---|---|
image_path | yes* | — | Local workspace file path to the source image |
image_url | yes* | — | Public HTTPS URL of the source image |
prompt | no | auto | Editing instruction (what to change) |
action | no | "edit" | Operation type (see §4) |
model | no | "nanopro" | Model: "nanopro" (fast ~25s) or "gpt" (best quality ~150s) |
aspect_ratio | no | None | Output ratio: 1:1, 3:4, 4:3, 9:16, 16:9. None = preserve original. |
*At least one of image_path or image_url must be provided. If both are given, image_path takes priority.
---
4. Actions — operation types
F: Multi-image / general editing
| Action | Key | Description |
|---|---|---|
| General edit | edit | Modify the image according to the prompt |
| Image blending | blend | Place a person/subject into a new background or scene |
| Outpainting | extend | Extend the image beyond its current boundaries |
| Local edit | local_edit | Modify only a specific region of the image |
| Text rendering | text_render | Add or modify text within the image |
| Multi-angle | multi_angle | Generate different viewing angles from one photo |
| Before/after | before_after | Generate a side-by-side comparison image |
G: Professional editing
| Action | Key | Description |
|---|---|---|
| Background replacement | replace_bg | Swap the background while keeping the subject |
| Super-resolution | upscale | Upscale and enhance image resolution |
| Photo restoration | restore | Repair scratches, tears, fading in old photos |
| Colorization | colorize | Add realistic colors to black-and-white photos |
| Person removal | remove_person | Remove a specific person from the photo |
V: Retouching / beauty
| Action | Key | Description |
|---|---|---|
| Portrait retouching | retouch | Skin smoothing, blemish removal, teeth whitening |
| Slimming | slim | Adjust facial and body proportions subtly |
| Enhancement | enhance | Color correction, lighting improvement, quality boost |
| Artistic filter | filter | Apply a specific artistic style or filter effect |
W: Medical / fitness comparison
| Action | Key | Description |
|---|---|---|
| Transformation comparison | comparison | Before/after for medical, fitness, or transformation |
X: Automotive
| Action | Key | Description |
|---|---|---|
| Car recolor | car_color | Change the color of a vehicle |
| Car wrap preview | car_wrap | Visualize a wrap or film on a vehicle |
---
5. Model selection guide
| Model | Key | Speed | Quality | Best for |
|---|---|---|---|---|
| NanoPro | nanopro | ~25s | Good | Default for all requests. Fast iteration. |
| GPT Image 2 | gpt | ~150s | Best | When user explicitly asks for "highest quality" or "best quality". Complex edits. |
Decision rules:
- Default: always use
nanoprounless the user explicitly requests higher quality. - Use
gptwhen: user says "highest quality", "best quality", "premium", or the edit requires very precise detail preservation (e.g., complex text rendering, fine inpainting). - Use
nanoprowhen: user wants fast results, is iterating on edits, or the edit is straightforward.
# Default (fast)
result = edit_image(image_path="photo.jpg", prompt="remove background", action="replace_bg")
# High quality (user requested)
result = edit_image(image_path="photo.jpg", prompt="remove background", action="replace_bg", model="gpt")
---
6. Intent recognition guide
Use this table to map user requests to the correct action:
General editing
| User says | Action | Prompt hint |
|---|---|---|
| "edit this photo", "modify this image" | edit | Pass user's instruction as prompt |
| "put me on a beach", "change the scene" | blend | Describe the target scene |
| "extend the image", "make it wider", "outpaint" | extend | Describe what to add |
| "change just the shirt color", "edit only the sky" | local_edit | Specify the region and change |
| "add text", "write 'Hello' on the image" | text_render | Specify text content and placement |
| "show from the side", "different angle" | multi_angle | Describe the desired angle |
| "before and after", "show the difference" | before_after | Describe the transformation |
Professional editing
| User says | Action | Prompt hint |
|---|---|---|
| "remove background", "change background", "换背景" | replace_bg | Describe the new background |
| "upscale", "make it higher resolution", "enhance quality" | upscale | Optionally specify target quality |
| "restore old photo", "fix this damaged photo", "修复老照片" | restore | Describe specific damage to fix |
| "colorize", "add color to B&W photo", "上色" | colorize | Optionally describe expected colors |
| "remove this person", "P掉某人" | remove_person | Describe which person to remove |
Retouching / beauty
| User says | Action | Prompt hint |
|---|---|---|
| "retouch", "smooth skin", "remove blemishes", "磨皮美白" | retouch | Specify retouching level |
| "make me thinner", "slim face", "瘦脸" | slim | Specify areas to adjust |
| "enhance colors", "improve lighting", "调色" | enhance | Describe desired look |
| "apply filter", "make it look vintage", "滤镜" | filter | Describe the filter style |
Medical / fitness
| User says | Action | Prompt hint |
|---|---|---|
| "before and after surgery", "fitness transformation" | comparison | Describe the transformation context |
Automotive
| User says | Action | Prompt hint |
|---|---|---|
| "change car color", "make it red", "汽车改色" | car_color | Specify the target color and finish |
| "car wrap", "vinyl wrap preview", "贴膜预览" | car_wrap | Describe wrap material and color |
---
7. Prompt engineering best practices
The prompt template system
Every action has a built-in prompt template that wraps the user's instruction for optimal results. You only need to pass the user's specific intent — the template adds the technical quality instructions automatically.
For example, if the user says "make the background a sunset beach":
result = edit_image(
image_path="photo.jpg",
prompt="a beautiful sunset beach with palm trees and golden light",
action="replace_bg",
)
# The script wraps this into: "Replace the background of this image: a beautiful
# sunset beach with palm trees and golden light. Keep the foreground subject
# perfectly intact with clean edges. Match the lighting direction..."
Key principles (from reference skills)
- Be specific about the change — vague prompts produce poor results:
- ❌ "make it better"
- ✅ "increase contrast, add warm golden tones, sharpen details"
- Describe what to preserve — especially for local edits:
- ❌ "change the shirt"
- ✅ "change the shirt color to navy blue, keep the same fabric texture and wrinkles"
- Specify materials and finishes — for car and product edits:
- ❌ "make it blue"
- ✅ "deep metallic blue with a glossy clear coat finish"
- Reference real-world styles — for filters and artistic effects:
- ❌ "make it artistic"
- ✅ "apply a warm cinematic color grade like Wes Anderson films"
- Describe the era for restoration/colorization:
- ❌ "colorize this"
- ✅ "colorize this 1940s family portrait with period-appropriate clothing colors"
- For retouching, specify the level:
- Light: "subtle skin smoothing, keep natural texture"
- Medium: "professional retouching, remove blemishes, even skin tone"
- Heavy: "full beauty retouching, smooth skin, brighten eyes, whiten teeth"
---
8. Usage examples by scenario
Background replacement
exec(open('skills/image-edit/edit_image.py').read())
# Simple background swap
result = edit_image(
image_path="uploads/portrait.jpg",
prompt="a modern office with floor-to-ceiling windows and city skyline view",
action="replace_bg",
)
# Studio background
result = edit_image(
image_path="uploads/product.jpg",
prompt="clean white studio background with soft shadow",
action="replace_bg",
)
Old photo restoration
# Repair damaged photo
result = edit_image(
image_path="uploads/old_family_photo.jpg",
prompt="repair all scratches, tears, and stains; restore faded colors; enhance clarity",
action="restore",
)
# Colorize black-and-white photo
result = edit_image(
image_path="uploads/grandpa_1945.jpg",
prompt="colorize with historically accurate colors for 1940s era, natural skin tones, period-appropriate clothing",
action="colorize",
)
Portrait retouching
# Professional retouching
result = edit_image(
image_path="uploads/selfie.jpg",
prompt="professional portrait retouching: smooth skin while keeping natural texture, remove blemishes, subtle teeth whitening, brighten eyes",
action="retouch",
)
# Slimming
result = edit_image(
image_path="uploads/photo.jpg",
prompt="subtle facial slimming, slightly more defined jawline, natural proportions",
action="slim",
)
Image enhancement
# Color grading
result = edit_image(
image_path="uploads/landscape.jpg",
prompt="cinematic color grading with warm golden tones, enhanced contrast, vibrant but natural colors",
action="enhance",
)
# Artistic filter
result = edit_image(
image_path="uploads/photo.jpg",
prompt="oil painting style with visible brushstrokes, rich warm palette, impressionist feel",
action="filter",
)
Super-resolution upscaling
result = edit_image(
image_path="uploads/low_res.jpg",
prompt="upscale to maximum quality, enhance fine details, reduce noise and compression artifacts",
action="upscale",
)
Person removal
result = edit_image(
image_path="uploads/group_photo.jpg",
prompt="remove the person on the far right, fill with the park background seamlessly",
action="remove_person",
)
Outpainting (image extension)
result = edit_image(
image_path="uploads/cropped.jpg",
prompt="extend the image to the left and right, continuing the mountain landscape naturally",
action="extend",
aspect_ratio="16:9",
)
Car customization
# Car recolor
result = edit_image(
image_path="uploads/my_car.jpg",
prompt="change to a deep cherry red metallic paint with glossy clear coat",
action="car_color",
)
# Car wrap preview
result = edit_image(
image_path="uploads/my_car.jpg",
prompt="matte black vinyl wrap with carbon fiber accents on the hood and mirrors",
action="car_wrap",
)
Before/after comparison
# Fitness transformation
result = edit_image(
image_path="uploads/fitness_photo.jpg",
prompt="create a fitness transformation comparison showing a more toned and fit version",
action="comparison",
)
Local editing
# Change specific element
result = edit_image(
image_path="uploads/outfit.jpg",
prompt="change only the dress color from red to emerald green, keep the same fabric texture",
action="local_edit",
)
Text rendering
result = edit_image(
image_path="uploads/poster_bg.jpg",
prompt="add the text 'SUMMER SALE' in bold white letters centered at the top, with a subtle drop shadow",
action="text_render",
)
High quality edit
# Use GPT model for best quality
result = edit_image(
image_path="uploads/important_photo.jpg",
prompt="professional color correction and enhancement for print publication",
action="enhance",
model="gpt",
)
---
9. Provided scripts
| File | Purpose |
|---|---|
edit_image.py | Core script: resolve image → build prompt → submit → poll → download. Handles local files (base64) and URLs, all actions, two models. |
exports.py | Re-exports edit_image, ACTIONS, ACTION_PROMPTS, MODELS for programmatic use by other skills. |
_cost_track.py | Cost tracking helper — records per-call costs via sc-proxy headers. |
---
10. Local testing
Set FAL_KEY env var to call fal.ai directly (bypasses sc-proxy):
# Basic edit
FAL_KEY=your-fal-key python3 skills/image-edit/edit_image.py photo.jpg "make it brighter" enhance nanopro
# Args: <image_path_or_url> [prompt] [action] [model]
---
11. Troubleshooting
| Problem | Fix |
|---|---|
File not found: ... | Check the workspace path; the file must exist |
Unsupported image format | Use .jpg, .jpeg, .png, .webp, or .bmp |
Image too large | Resize to under 10 MB before uploading |
image_url must be a public HTTP(S) URL | Use image_path for local files, or provide a valid https:// URL |
Unknown action | Check valid actions in §4 |
HTTP 402 insufficient_credits | Top up balance; cost is pre-charged on submit |
HTTP 403 endpoint_not_allowed | sc-proxy only allows approved fal endpoints; contact admin |
Edit FAILED upstream | Simplify prompt, ensure source image is clear, retry |
Job stuck IN_PROGRESS >10 min | Save request_id, retry later |
| Poor edit quality | Try model="gpt" for higher quality; be more specific in prompt |
| Background not fully removed | Use replace_bg action with explicit background description |
| Retouching looks unnatural | Add "keep natural texture" or "subtle" to prompt |
---
12. Infrastructure (reference)
- Caller →
sc-proxy→queue.fal.run/{model}→ fal model providers - All requests must include
Authorization: Key fake-falai-key-12345(proxy injects the realFAL_KEY) - Pre-charge happens at submit. Poll/result calls are free.
- Local files are base64-encoded as data URIs — no separate upload step needed.
- Final images live at
https://*.fal.media/...— public CDN, no auth needed for download. - Cost tracking via
_cost_track.py— recordsX-Credits-Usedfrom sc-proxy response headers.
Model endpoints
| Model | Edit endpoint |
|---|---|
| nanopro | fal-ai/nano-banana-pro/edit |
| gpt | openai/gpt-image-2/edit |
---

