imagemagick-image-operations

Describe the outcome you want, such as making a 300x300 square thumbnail or converting PNGs to JPEG, and the agent builds the correct magick command. It inspects the input first, orders settings before operators, and validates the output dimensions and format afterward.

Use mogrify with -path pointing to a new output directory, since mogrify overwrites its inputs in place by default. The skill enforces this pattern and never passes -- to mogrify, which would create a file literally named -- while exiting 0.

When the output coder cannot be resolved, ImageMagick silently falls back to the input's format, writes it under the requested filename, and exits 0. The fix is an explicit FORMAT: prefix on the output and verifying the result with identify -format '%m'.

Support depends on the build, not the version string; magick -version can advertise delegates whose coder modules are missing from disk. The skill's preflight script detects this delegate/coder mismatch and uses a round-trip encode probe as the only reliable check.

Many distributions disable PDF, PS, and EPS in policy.xml for security, producing an 'operation not allowed by the security policy' error. Detect it with magick -list policy; it is a deliberate restriction, not a missing Ghostscript installation.

Untrusted input is a real attack surface given ImageMagick's CVE history with MSL, MVG, and URL coders. The skill quotes all paths, requires ./ or FORMAT: prefixes, rejects @ listfiles, sets -limit resource caps, and recommends a restrictive policy.xml.