subtitle-burner

Burn an SRT subtitle file into an MP4 via ffmpeg's subtitles filter (libass). Single-pass re-encode of video; audio copied as-is. Uses a verified managed Noto Sans CJK font when available. Used by meta-short-drama as the final subtitling step after merge.

Quality

73%

Does it follow best practices?

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Securityby

Low

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tessl review fix ./src/opensquilla/skills/bundled/subtitle-burner/SKILL.md

Quality

Content

88%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.

The content is concise, well-structured, and explicit about validation and failure handling for a re-encoding operation; its main gap is the absence of an inline copy-paste command block and an explicit pointer to the bundled burn.py script.

Suggestions

Add a short copy-paste invocation example (with a few representative --* flags) so the body is immediately executable without consulting the frontmatter.

Explicitly reference scripts/burn.py in the body so the bundled implementation is clearly signaled as the referenced detail.

Consider a one-line 'Failure mode' pointer to the stderr-tail behavior so diagnosis is front-and-center for operators.

Dimension	Reasoning	Score
Conciseness	The body is lean and operational — a focused inputs table plus terse Output/Dependencies/Path-escaping/Style-chain sections with no padding about what MP4/SRT/libass are; every token earns its place, matching the score-5 anchor.	5 / 5
Actionability	Concrete, actionable guidance via the per-flag inputs table (defaults, ranges, units) and frontmatter entrypoint command, but the body itself contains no copy-paste command/code block, fitting 'mostly executable guidance with minor gaps'.	4 / 5
Workflow Clarity	Validation and failure handling are explicit ('ffprobe to confirm a decodable positive-duration video stream', 'atomically replace the destination only after validation', non-zero exit with 2.5 KB stderr tail, SUBTITLES_SKIPPED empty-SRT path), satisfying the validation checkpoint bar for this re-encode operation.	5 / 5
Progressive Disclosure	Well-organized single-file body with clearly labeled sections and no nested references, but the scripts/burn.py bundle is referenced only via the entrypoint rather than being explicitly signaled as a navigation pointer in the body.	4 / 5
	Total	18 / 20 Passed

Description

58%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.

The description is concrete and specific about what the skill does, but it lacks an explicit 'Use when...' trigger and leans on technical jargon over natural user phrasings, capping completeness and trigger quality at the midpoint.

Suggestions

Add an explicit trigger clause, e.g. 'Use when hardcoding/burning SRT subtitles into an MP4, especially for CJK-language short-drama output.'

Include natural user-facing synonyms alongside the technical terms (e.g. 'hardcode subtitles', 'hard burn subs', 'embed subtitles into video').

Mention the .srt file extension and 'subtitle burn-in' phrasing to broaden natural keyword coverage.

Dimension	Reasoning	Score
Specificity	Lists several concrete actions ('Burn an SRT subtitle file into an MP4', 'Single-pass re-encode of video; audio copied as-is', managed Noto Sans CJK font) with only minor coverage gaps, matching the score-4 anchor.	4 / 5
Completeness	The 'what' is clear but the only 'when' guidance ('Used by meta-short-drama as the final subtitling step after merge') is an orchestration hint rather than an explicit 'Use when...' trigger, which per the rubric caps completeness at 3.	3 / 5
Trigger Term Quality	Contains relevant technical terms (SRT, MP4, ffmpeg, libass) but they skew toward jargon and lack the natural user phrasings or synonyms users would say, fitting the 'some relevant keywords but missing common variations' anchor.	3 / 5
Distinctiveness Conflict Risk	The libass/CJK-font subtitling niche plus the meta-short-drama positioning make it mostly distinct with only minor overlap risk against general ffmpeg skills, matching the score-4 anchor.	4 / 5
	Total	14 / 20 Passed

Validation

81%

Warnings & errors only

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

Validation — 13 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning
metadata_field	'metadata' should map string keys to string values	Warning
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	13 / 16 Passed

Repository: TokenRhythm/opensquilla
Path: src/opensquilla/skills/bundled/subtitle-burner/SKILL.md
Commit: 94ac35e

Reviewed: 4 days ago

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