The Agent Skills Directory

[COMMAND_EXECUTION]: The skill uses Bun.spawn to execute several system commands, including ffmpeg and ffprobe for media transcoding, probing, and splitting, as well as curl for uploading files to Volcano TOS.
[EXTERNAL_DOWNLOADS]: The downloadRemote function in scripts/lib/source.ts allows the skill to download media files from arbitrary URLs provided by the user via the --url flag.
[REMOTE_CODE_EXECUTION]: The ensureFfmpegInstalled function in scripts/lib/ffmpeg.ts provides a routine to install the ffmpeg package using system package managers (brew, apt-get, dnf, pacman). While this involves executing installation scripts, it is presented as a prerequisite setup step and generally requires user confirmation unless the --yes flag is explicitly provided.
[DATA_EXFILTRATION]: The skill is designed to read local files (provided via --path) and upload them to a Volcano TOS bucket. While this is the intended primary function of the tool for processing local media with the Ark API, it represents a capability that handles sensitive data (user media) and transmits it to a remote cloud service based on user-provided credentials.
[INDIRECT_PROMPT_INJECTION]: The skill processes untrusted external data such as subtitles and transcripts which are interpolated into prompts for the Ark multimodal model.
Ingestion points: Untrusted data enters the context via --subtitle, --transcript, --prompt, and media file content (audio/video).
Boundary markers: The skill uses delimiters like 「<transcript>」 in scripts/lib/prompts.ts to separate user-provided text from system instructions.
Capability inventory: The skill has command execution capabilities via Bun.spawn for ffmpeg, ffprobe, and curl (used for media processing and TOS uploads).
Sanitization: Shell arguments for external commands are sanitized using quoteShellArg or passed as argument arrays to Bun.spawn, which mitigates shell injection risks.

doubao-multimodal