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media-processing

Video/audio/image processing with FFmpeg and ImageMagick. Tools: FFmpeg (video/audio), ImageMagick (images). Capabilities: format conversion, encoding (H.264/H.265/VP9/AV1), streaming (HLS/DASH), filters, effects, thumbnails, watermarks, batch processing, hardware acceleration (NVENC/QSV). Actions: convert, encode, resize, crop, compress, extract, merge, stream, transcode media. Keywords: FFmpeg, ImageMagick, video encoding, audio extraction, image resize, thumbnail, watermark, HLS, DASH, H.264, H.265, VP9, AV1, codec, bitrate, framerate, resolution, aspect ratio, filter, overlay, concat, trim, fade, batch processing. Use when: converting video/audio formats, encoding with specific codecs, generating thumbnails, creating streaming manifests, extracting audio from video, batch processing images, adding watermarks, optimizing file sizes.

69

Quality

84%

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SKILL.md
Quality
Evals
Security

Quality

Content

76%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A well-organized, highly actionable reference with excellent code examples and clean progressive disclosure to six reference guides. The main weaknesses are the absence of validation/backup checkpoints in the destructive batch (mogrify) workflows and the complete omission of the bundled Python scripts from the body's documentation.

Suggestions

Add an explicit validation step to the batch workflows, e.g. back up originals before mogrify ('cp -r ./images ./images.bak' or use a -path output directory) and verify a sample output before applying to the full set.

Document the bundled scripts in a 'Scripts' section (batch_resize.py, media_convert.py, video_optimize.py) with one-line descriptions and invocation examples so they are discoverable.

Deduplicate the 'When to Use This Skill' section against the frontmatter description, and trim 'Advanced Techniques' entries that duplicate references/ffmpeg-encoding.md and references/ffmpeg-filters.md content to shorten the body.

DimensionReasoningScore

Conciseness

The body is lean and code-first: no concepts are explained that Claude doesn't already know, and sections like "Common Parameters" and "Performance Tips" are compact. Not a 5: the "When to Use This Skill" list largely restates the frontmatter description, and some "Advanced Techniques" examples (multi-pass encoding, complex filter chains) duplicate content already delegated to references/*.md. Not a 3: the over-explanation and padding are minor, not 'some unnecessary explanation'.

4 / 5

Actionability

Commands are copy-paste ready and executable across the common cases: "ffmpeg -i input.avi -c:v libx264 -crf 22 -c:a aac output.mp4", "mogrify -path ./optimized -format jpg -quality 85 -strip *.png", the palette-based GIF pipeline, and ffprobe JSON inspection. Not a 4: the examples are complete, correct, and cover the full breadth of the skill's stated use cases with only a trivial blemish (the redundant -c:v in the QSV example).

5 / 5

Workflow Clarity

The skill is a recipe collection with a useful Decision Matrix, but destructive batch operations have no validation checkpoint: "mogrify -resize 800x -quality 85 *.jpg" overwrites originals in place and "Batch Image Optimization" converts files in bulk with no backup, dry-run, or verify step embedded in the flow ("Test on samples" appears only as a detached tip). Per the rubric's batch-operations guideline, workflow clarity is capped at 3. Not a 4: for batch/destructive work the missing validation is exactly the gap the cap targets; not a 2: sequences and commands themselves are clear and well-organized.

3 / 5

Progressive Disclosure

The six references/*.md files are real, well-signaled, one level deep, and listed with one-line descriptions under "Reference Documentation"; the body stays an overview with inline quick-start examples. Not a 5: the bundle also contains scripts/batch_resize.py, scripts/media_convert.py, and scripts/video_optimize.py that are never mentioned anywhere in the body, so a whole capability layer of the skill is undiscoverable. Not a 3: structure and reference signaling are otherwise good.

4 / 5

Total

16

/

20

Passed

Description

92%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description that clearly states what the skill does, when to use it, and which tool handles which domain, with explicit trigger phrases and a rich keyword list. The only weakness is mild padding from the exhaustive 'Keywords:' enumeration, which could trade a few technical terms for natural user phrasings and file extensions.

DimensionReasoningScore

Specificity

The description lists many concrete actions ("convert, encode, resize, crop, compress, extract, merge, stream, transcode media") alongside specific capabilities ("streaming (HLS/DASH)", "hardware acceleration (NVENC/QSV)"), matching the anchor for multiple specific concrete actions with comprehensive coverage. Not a 4: coverage spans video, audio, and image domains with named codecs and operations, leaving only trivial gaps.

5 / 5

Completeness

It explicitly answers both questions: the "what" ("Video/audio/image processing with FFmpeg and ImageMagick... format conversion, encoding... filters, effects, thumbnails, watermarks, batch processing") and an explicit "Use when:" clause with concrete trigger phrases ("converting video/audio formats, encoding with specific codecs, generating thumbnails, creating streaming manifests, extracting audio from video..."). This directly matches the top anchor.

5 / 5

Trigger Term Quality

Good keyword coverage including natural terms users would say ("thumbnail", "watermark", "audio extraction", "image resize", "codec", "bitrate", "concat", "trim"), but a few natural phrasings and file extensions are missing (e.g. .mp4, .png, "make a GIF", "convert to MP3"). Not a 5: the keyword list omits the synonym/extension layer the top anchor expects; not a 3: far more than 'some relevant keywords'.

4 / 5

Distinctiveness Conflict Risk

A clear niche (FFmpeg for video/audio, ImageMagick for images) with distinct triggers like "HLS", "DASH", "NVENC/QSV", "palette", minimizing conflict with other skills. Not a 4: the FFmpeg/ImageMagick split and streaming/hardware-acceleration specifics make overlap risk minimal rather than minor.

5 / 5

Total

19

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
samhvw8/dot-claude
Reviewed

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