Image Processing

Translate a user’s natural-language request into a safe invocation of the image-processing CLI.

Contract

Prereqs:

• •Run inside a git work tree (recommended; enables stable out/ paths).
• •image-processing available on PATH (install via brew install nils-cli).
• •ImageMagick:
  • •magick (preferred), or
  • •convert + identify.
• •Optional (used by optimize when available; otherwise falls back):
  • •WebP: cwebp + dwebp
  • •JPEG: cjpeg + djpeg

Inputs:

• •Natural-language user intent (assistant translates into a command).
• •One or more input paths via --in (file or directory).
• •For output-producing subcommands: exactly one output mode:
  • •--out <file> (single input only), or
  • •--out-dir <dir> (batch), or
  • •--in-place --yes (destructive).

Outputs:

• •Processed image file(s) under the chosen output mode.
• •Optional artifacts under out/image-processing/runs/<run_id>/:
  • •summary.json (when --json or --report is used)
  • •report.md (when --report is used)
• •Assistant response (outside the script) must include:
  • •Output file/folder paths as clickable links (inline code)
  • •A suggested “next time” prompt to repeat the same task

Exit codes:

• •0: success
• •1: failure
• •2: usage error

Failure modes:

• •Missing required tools (image-processing binary, ImageMagick).
• •Invalid or ambiguous flags (missing output mode, missing required params).
• •Output collisions in batch mode (multiple inputs map to the same output).
• •Output already exists without --overwrite.
• •Disallowed operations:
  • •--in-place without --yes
  • •Alpha → JPEG without --background

Guidance

Preferences (optional; honor when provided)

• •Output mode: --out / --out-dir / --in-place --yes
• •Format: png / jpg / webp
• •Geometry intent: width/height/scale/aspect, --fit contain|cover|stretch, --gravity
• •Quality / metadata: --quality, --strip-metadata, --background (required for alpha → JPEG)
• •Reproducibility: --dry-run, --json, --report

Policies (must-follow per request)

1. •

   If underspecified: ask must-have questions first

   • •Use: skills/workflows/conversation/ask-questions-if-underspecified/SKILL.md
   • •Ask 1–5 “Need to know” questions with explicit defaults.
   • •Do not run commands until the user answers or explicitly approves assumptions.
2. •

   Single entrypoint (do not bypass)

   • •Only run: image-processing (from PATH; install via brew install nils-cli)
   • •Do not call ImageMagick binaries directly unless debugging the image-processing CLI itself.
3. •

   Output mode gate (exactly one)

   • •For output-producing subcommands, require exactly one of:
     • •--out <file> (single input only)
     • •--out-dir <dir> (batch)
     • •--in-place --yes (destructive; requires explicit user intent)
4. •

   Completion response (fixed)

   • •After a successful run, respond using:
     • •skills/tools/media/image-processing/references/ASSISTANT_RESPONSE_TEMPLATE.md
   • •Include clickable output path(s) and a one-sentence “next prompt” that repeats the same task with concrete paths/options.

References

• •skills/tools/media/image-processing/references/IMAGE_PROCESSING_GUIDE.md
• •skills/tools/media/image-processing/references/ASSISTANT_RESPONSE_TEMPLATE.md