set-metadata

name	set-metadata
description	Write EXIF, IPTC, and XMP metadata tags to image files. Use when you need to add or update metadata like artist name, copyright, description, keywords, or GPS coordinates on individual images.
disable-model-invocation	false
allowed-tools	Bash(exiftool *), Bash(ls *), Bash(find *), Bash(cp *), Bash(rm *), Read, Write

Write Metadata to Images

Set metadata tags on image files using exiftool. Supports EXIF, IPTC, and XMP metadata, with automatic backup of original files.

When to use

• Adding copyright and artist information to a photo before distribution.
• Manually setting GPS coordinates if they were not captured.
• Batch-updating descriptions or keywords across multiple images.
• Fixing incorrect camera model or lens metadata.

Inputs to gather

• Input file or directory — single image or folder.
• Metadata key-value pairs — ask the user for the tags and values they want to set. Common fields:
  • Artist — photographer or creator name.
  • Copyright — copyright statement (e.g., "© 2026 Daniel Rosehill").
  • Description / ImageDescription — image description text.
  • Keywords — comma-separated keywords.
  • LensModel — lens description (if not auto-detected).
  • GPSLatitude / GPSLongitude / GPSAltitude — GPS coordinates.
  • DateTimeOriginal — capture date/time (format: YYYY:MM:DD HH:MM:SS).
• Backup before write? Default: yes. exiftool creates _original sidecars; offer an explicit backup copy for safety.

Procedure

1. Check tooling

command -v exiftool || echo "exiftool not installed — install with: sudo apt install libimage-exiftool-perl"

Abort if missing.

2. Validate tag names

Ask the user to confirm the exiftool tag names. Common mappings:

User-facing	exiftool tag
Artist	Artist
Creator	Creator
Copyright	Copyright
Description	ImageDescription
Keywords	Keywords
Lens	LensModel
Camera model	Model

Gotcha: EXIF, IPTC, and XMP may use different tag names for the same logical field. exiftool auto-detects the appropriate target; document which format will be used:

exiftool -a -G1 "<sample.jpg>" | grep -i copyright

This shows which groups (EXIF, IPTC, XMP) currently carry copyright info on the sample file.

3. Confirm metadata and scope

Print a summary:

• Tags to be set: list all key-value pairs.
• Target files: count and confirm.
• Backup location: where _original sidecars will be stored.
• Confirm before proceeding.

4. Backup (if requested)

# exiftool creates _original sidecars by default, but also offer explicit backup
mkdir -p backup/
cp -r "<target>" backup/

5. Write metadata

Single file:

exiftool -Artist="Daniel Rosehill" -Copyright="© 2026 Daniel Rosehill" \
  -ImageDescription="Sample photo" "<file.jpg>"

Multiple tags at once:

exiftool \
  -Artist="<artist>" \
  -Copyright="<copyright>" \
  -ImageDescription="<desc>" \
  -Keywords="<key1>,<key2>" \
  "<file.jpg>"

Batch (directory or recursive):

find <target> -maxdepth <1|999> -type f \
  \( -iname '*.jpg' -o -iname '*.jpeg' -o -iname '*.png' \
     -o -iname '*.heic' -o -iname '*.webp' -o -iname '*.tif' \) \
  -exec exiftool -Artist="<artist>" -Copyright="<copyright>" {} \;

Append -overwrite_original to discard _original sidecars, but only if a backup was made in step 4.

6. Verify

Sample a few output files and confirm the metadata was written:

exiftool -Artist -Copyright -ImageDescription "<sample.jpg>"

If metadata did not stick (e.g., PNG text chunks), try the XMP-specific path:

exiftool -XMP:Artist="<artist>" -XMP:Copyright="<copyright>" "<file.png>"

7. Cleanup (optional)

If the user accepted -overwrite_original, remove _original sidecars:

find <target> -maxdepth <1|999> -type f -iname '*_original' -delete

Output / side effects

• Metadata tags written to original files (or to a copy if the user requested a separate output directory).
• _original sidecars created in the same directory as each file (unless -overwrite_original was used).
• Original files are modified (unless a backup was made in step 4).

Notes

• EXIF vs. IPTC vs. XMP: The same field (e.g., copyright) can live in EXIF, IPTC, and/or XMP. Some readers check only one format. exiftool intelligently maps to the appropriate group, but document which format was used:
  • EXIF: structured, camera/lens/exposure info. Limited size.
  • IPTC: editorial metadata (keywords, description, copyright). Limited size.
  • XMP: extensible, can hold arbitrary key-value pairs.
• PNG and HEIC: exiftool writes metadata to PNG as XMP in iTXt chunks. HEIC is complex; check the _original sidecar to ensure metadata persisted.
• Tag size limits: EXIF and IPTC have field-length limits. Very long descriptions (>500 chars) should go in XMP. exiftool warns if a value is too large.
• Permanent writes: Always create a backup before bulk metadata writes. Metadata corruption is rare but possible.
• Preserve other metadata: By default, exiftool -Tag=value file preserves all other metadata. Use -all= if you want to nuke everything before writing (not recommended).
• Depends: apt install libimage-exiftool-perl.