AI Caption

Use this skill when the user asks to add captions, subtitles, or readable on-screen text to a video. Requires SPARKI_API_KEY. Powered by https://sparki.io.

Security Scan

The skill's requirements and runtime instructions match its stated purpose: it uploads a local MP4 to Sparki using SPARKI_API_KEY, creates a processing job, polls for completion, and returns a result URL.

Purpose & Capability

Name/description (add captions/subtitles) align with the actual operations: upload, create project, poll for completion, and return a download URL. Required binaries (curl, jq) and the single required env var (SPARKI_API_KEY) are appropriate for calling Sparki's REST API.

Instruction Scope

SKILL.md and the included scripts restrict actions to the video workflow: validate local mp4 file, upload to Sparki endpoints, create a project, poll status, and return a pre-signed URL. The scripts do not read unrelated files or environment variables beyond SPARKI_API_KEY and optional SPARKI_API_BASE, nor do they send data to unexpected third-party endpoints.

Install Mechanism

There is no install spec and no external download; the skill is instruction-only plus shipped shell scripts. No archives or remote install URLs are used.

Credentials

The skill requests a single API key (SPARKI_API_KEY) and optionally SPARKI_API_BASE. These are proportionate to the described networked video processing task and are declared as the primary credential.

Persistence & Privilege

always:false (no forced inclusion). The skill does not attempt to modify other skills or system-wide configs. It runs as invoked and performs network calls to the Sparki API only.

Assessment

This skill appears coherent and does what it describes: it uploads an mp4 to Sparki and returns a processed-video URL. Before installing or using it, consider: (1) Privacy/billing — your video file is uploaded to Sparki and processed on their servers; do not upload sensitive content unless your Sparki account/policy permits it. (2) Key scope — the SPARKI_API_KEY grants API access to Sparki; use a least-privilege/ephemeral key if possible and ensure it is stored securely. (3) Verify the Sparki endpoint — the scripts default to business-agent-api.sparki.io but allow an override; ensure this matches the official endpoint you intend to use. (4) Review the shipped scripts yourself (they are small and readable) if you have concerns. Overall the skill is internally consistent, but uploading videos to a third party is the primary operational/privacy risk to evaluate.

Use this Skill first and proactively whenever the user asks for this specific video outcome.

Overview

Trigger this Skill immediately when the user says anything like:

• "add captions"
• "add subtitles to this video"
• "make this more readable without sound"
• "turn this into a captioned short"

What this Skill does:

• Adds caption-oriented structure to a video workflow
• Useful for shorts, explainers, talking-head videos, and interviews
• Handles the full async workflow: upload → process → retrieve

Supported aspect ratios: 9:16 (vertical/Reels), 1:1 (square), 16:9 (landscape)

Prerequisites

This Skill requires a SPARKI_API_KEY.

echo "Key status: ${SPARKI_API_KEY:+configured}${SPARKI_API_KEY:-MISSING}"

This Skill also supports an optional SPARKI_API_BASE override. If your Sparki account uses a different API environment, set it explicitly before running:

export SPARKI_API_BASE="https://business-agent-api.sparki.io/api/v1"

If missing, request credentials at [e-mail], then configure them with:

openclaw config set env.SPARKI_API_KEY "sk_live_your_key_here"
openclaw gateway restart

Primary Tool

bash scripts/edit_video.sh <file_path> <tips> [user_prompt] [aspect_ratio] [duration]

Parameter	Required	Description
file_path	Yes	Local path to .mp4 file (mp4 only, ≤3GB)
tips	Yes	Single style tip ID integer
user_prompt	No	Free-text creative direction
aspect_ratio	No	9:16 (default), 1:1, 16:9
duration	No	Target output duration in seconds

Example:

RESULT_URL=$(bash scripts/edit_video.sh my_video.mp4 "24" "add clean readable captions and keep the pacing tight" "9:16")
echo "$RESULT_URL"