
Thumbnails
io.github.theluckystrikePublished by GitHub account theluckystrikev0.22.6Updated Oct 24, 2026
Generate image thumbnails, resize, convert and compress photos from your AI chat. Local files.
Overview
Local MCP server that lets an assistant inspect, resize, convert, compress, crop, thumbnail and watermark images on your own machine.
- What you can do
- Inspect images: format, dimensions, aspect ratio, alpha channel and bytes per pixel
- Resize, crop and batch-resize files, keeping aspect ratio or fitting a target box
- Convert between PNG, JPEG, BMP, GIF and TIFF, and compress toward a byte target with before-and-after counts
- Generate folder thumbnails, add a text or business-name watermark, and strip EXIF, GPS and other metadata
- Report dominant colours as hex codes, plus license status and activation
- Review the last 25 operations through a resource, and run a prepare-for-web prompt
- When to use it
- Useful when you want routine image chores done from chat without uploading client photos to a web tool: shrinking photos for a website, converting formats, making thumbnails of a folder, or removing GPS data before sending a file.
- Requirements
- Runs as a local process on your machine (desktop only) and needs Node.js 18 or later. The npm package is described as not yet published, so the .mcpb bundle or a clone-and-build is the working install path. No account or network access is required; an optional MCP_LICENSE_KEY enables Pro features.
Installation
In SourceWeft
- Open Thumbnails in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Other MCP clients
Follow the launch instructions in the repository.
README
mcp-image
Say "make these five photos 1200 pixels wide" or "shrink this screenshot and strip the GPS out of it" and it happens, on your machine, in a second. This MCP server does the small image jobs that otherwise send you to a web uploader: resize, convert between PNG, JPEG, BMP, GIF and TIFF, compress with a real before-and-after byte count, crop, thumbnail a folder, watermark with your business name, and drop the EXIF block a phone camera writes into every photo. No upload, no account, no native dependency, no image editor.
In the official MCP Registry (io.github.theluckystrike/image-resize-convert-compress-watermark).
Listed on the AI Product Index - live remote endpoint at mcp.zovo.one/s/image, free tier, no signup.
The image chores of a freelance business, done from chat instead of from a browser tab you would rather not hand a client photo to.
60-second install
npm publish for @theluckystrike/mcp-image is pending. Until then, the .mcpb one-click bundle or a clone+build
is the working path, both are verified below.
One-click (.mcpb): download image.mcpb from the latest release and double-click it in Claude Desktop:
https://github.com/theluckystrike/mcp-servers/releases/latest
(claude_desktop_config.json):
Claude Code:
(.cursor/mcp.json):
The npx form above starts working the moment the package is published. Until then, use the .mcpb bundle above, or
build from source with exactly these three commands:
Then point your client's command at node with one arg: the absolute path to servers/image/dist/index.js.
To run in Pro mode set MCP_LICENSE_KEY in the same config block, or call license_activate once with your key.
Tools
Resource: image://recent returns the last 25 operations, newest first, with the inputs, the files written and when.
Prompt: prepare_for_web takes a camera-sized image down to a page-sized JPEG, drops the metadata that came with it, and reports the bytes saved.
What you can say
Worked example
The JPEG re-encode also drops the EXIF block the camera wrote, including the GPS coordinates. The original file is byte-for-byte unchanged.
Free vs Pro
The free limit is on what gets written, not on what gets read: a 12 MP phone photo taken down to 1600 px wide is a free call, because that is the job. Writing 12 MP back out again is the Pro one.
A tier limit is an answer, not an error, and nothing is written when one refuses a call.
Pro is a one-time $19, or $39 for every server in the collection, lifetime.
quality is a JPEG parameter, and only a JPEG parameter
This is the one thing about image compression that surprises people, so the server says it in its own answer rather
than accepting a number and quietly doing nothing with it. A JPEG throws away detail to get smaller, and quality
is the dial for how much. A PNG is lossless: there is no dial. Passing quality: 40 to a PNG output does not make
a PNG 60% smaller, it makes exactly the same PNG.
So the output format follows the extension of your out_path, and that is the lever:
out_path: "shot-small.jpg",qualityapplies, and a photo typically drops 80-95%.out_path: "shot-small.png",qualityis reported as not applicable, and onlymax_widthremoves bytes.
Palette quantisation was measured as an alternative for PNG and rejected: re-encoding a 300x220 noisy PNG through a 16-colour quantiser produced a larger file (115,451 bytes against 39,262), because the encoder here writes RGBA either way and quantising only destroys the row-to-row similarity that the deflate step was exploiting. A tool that claims to compress and returns a bigger file is worse than a tool that says which knob exists.
image_compress therefore always reports the byte count before and after, the percentage, and the method that did
the work, and, if the output came out larger, it says so and tells you to keep the original.
Decompression bombs are refused from the header, before anything decodes
A 4 KB PNG can declare that it is 20,000 by 20,000 pixels. Decoding it allocates 1.6 GB of RGBA and takes the process down before any size check written after the decode could ever run. So the declared dimensions are read out of the container header, PNG IHDR, the JPEG SOF segment, the GIF logical screen descriptor, the BMP info header, the first TIFF IFD, and a file over 10,000 px on a side is refused there, with the memory it would have taken named in the message:
The decoded size is checked again afterwards, because a header probe can come back empty on an unusual TIFF, and a guard that only sometimes runs is not a guard.
Existing files are never overwritten, and inputs are never modified
Every tool writes a new file and leaves its inputs byte-for-byte alone, there is no in-place mode, on purpose.
An out_path that already exists is refused:
The path is reserved with an exclusive create, not an existence check, so two processes writing the same out_path
at the same time cannot clobber each other: one wins, the other is refused and writes nothing. image_thumbnails
and image_batch_resize reserve every one of their output paths before writing any of them, so a collision on file
3 does not leave files 1 and 2 behind as a half-done batch, and the reservations are released, so nothing empty is
left on disk either.
Pass overwrite: true when replacing the file is what you want.
overwrite: true still does not let an output be an input. Writing a result back over one of its own sources
destroys that source, the pixels are already decoded in memory and get written over the file they came from, so a
4000 px original becomes the 512 px thumbnail and every later read of that path is quietly wrong. So an out_path
that resolves to (or shares an inode with) any input of the same call is refused before any work happens.
What "strip metadata" actually does
image_strip_metadata decodes the image and re-encodes it from the raw pixels. EXIF, GPS coordinates, the camera
and lens, the capture time, XMP packets and embedded colour profiles are not removed one by one, they are simply
never handed to the encoder, so they cannot come out the other side. Two consequences worth knowing:
- The pixels are the same, the bytes are not. A JPEG goes through the encoder a second time, so the copy is not bit-identical to the original even though it looks the same. Keep the original if that matters.
- Every other writing tool here has the same effect as a side effect. Resizing a photo also drops its EXIF.
Limits
- Inputs over 50 MB are refused: an image decodes to width x height x 4 bytes of raw RGBA regardless of how well it is compressed on disk.
- 10,000 px per side, checked from the header first and from the decode second.
- Read and written: PNG, JPEG, BMP, GIF and TIFF, detected by magic bytes rather than by file extension. No WebP, no AVIF, no HEIC, no SVG, there is no pure-JavaScript decoder for those that is worth shipping, and this server takes no native dependency.
- An animated GIF is read as its first frame. This server does not do animation.
- Watermark text is drawn with the bundled Open Sans bitmap faces (8, 16, 32, 64 and 128 px), and the largest one that fits the image is chosen. A character those faces do not carry is not drawn, so there is no CJK watermark.
- No rotation, no filters, no colour correction, no OCR, no background removal. This server does the size-and-format jobs; it is not an image editor.
How it stores data
Only a register of what it did: ${XDG_DATA_HOME:-~/.local/share}/mcp-servers/image/operations.json, the last 500
operations, as plain JSON. Your images stay where you put them. Every write to the register runs inside an advisory
lock on .../image/.lock, so two clients on one data directory cannot lose a record, and saves go to a temporary
file and are renamed into place.
If the register is unreadable or not valid JSON it is never treated as "empty": it is moved aside byte-for-byte as
operations.json.corrupt-<timestamp> with a marker beside it. The image you asked for is still written, the file
is on disk before the register is touched, and the answer tells you the history could not be updated.
The watermark reads the one shared profile the whole suite uses,
${XDG_DATA_HOME:-~/.local/share}/mcp-servers/profile/business.json, written by business_set in mcp-invoice or
mcp-docx. Nothing is invented: with no name stored and no text passed, image_watermark refuses and says which tool
to run.
Privacy
All data stays local. The server reads and writes files on your machine and makes no network request of any kind -- not for licensing (keys are verified offline), not for fonts, not for telemetry. A client photo you resize is never uploaded anywhere, which is the entire reason this exists.
Pairs with
- mcp-docx, size a logo here, then put it in the letterhead:
image_resizeto the header height, then the.docxwriter picks the file up from disk. - mcp-pdf, shrink the scans before you merge them, so the joined PDF is not 40 MB.
- mcp-resume, one correctly sized, metadata-free headshot for the CV and the application form.
- office-suite, several servers behind one install, one config entry.
Troubleshooting
npxhangs or fails to find the package: npm publish for this package is pending. Use the.mcpbbundle or the clone-and-build path above until it lands.- "quality does not apply to a PNG output": write to a
.jpgout_path, or passmax_width. See the section above. - "declares NxN pixels ... and was refused before decoding": the file claims a canvas over 10,000 px per side. If it is genuinely that large, resize it with a tool that streams tiles; this server decodes whole images.
- "does not start with the magic bytes": the file is not a PNG, JPEG, BMP, GIF or TIFF. A
.pngname on a WebP file is the usual cause; convert it first. - "already exists and nothing was written": pass
overwrite: true, or a differentout_path. - The watermark is tiny: the largest bundled face is 128 px, and it is chosen to fit within 80% of the image width. On a very large photo, resize first and watermark second.
- Node version: requires Node >= 18. Check with
node -v.
MIT licensed. Support: [email protected]
Built by theluckystrike.
Use these docs as an MCP server
Any MCP client (Claude, Cursor, Windsurf, VS Code) can read this repository's documentation directly via GitMCP - no install:
- Docs MCP URL: https://gitmcp.io/theluckystrike/mcp-image
Source: servers/image/README.md at commit 6535b33
Tools
0Version history
3- v0.22.6LatestOct 14, 2026
- v0.22.3Sep 23, 2026
- v0.21.0Sep 16, 2026
Score
50% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
- Reached in the last 30 days25 pts
Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.
- Auth declared10 pts
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
- Tools listed15 pts
Answer tools/list without a credential, or ship a package that starts in a sandbox without one.
- DescriptionRequired15 pts
- Logo10 pts
- Documentation15 pts
- License10 pts