Video To Audio Converter

Tired of scrubbing through video files just to get the audio you actually need? This video-to-audio-converter skill pulls clean audio tracks directly from yo...

Security Scan

The skill mostly matches its stated purpose (upload a video and get back audio), but there are inconsistencies and a privacy risk (it may put an auth token into a shareable URL), so review before installing or using with sensitive content.

Purpose & Capability

The skill's required credential (NEMO_TOKEN) and declared config path (~/.config/nemovideo/) align with a cloud-based NemoVideo extractor. However, the manifest declares NEMO_TOKEN as required/primary even though the SKILL.md describes automatically obtaining an anonymous token if none is present — an internal inconsistency about whether the environment token is mandatory or optional.

Instruction Scope

Instructions explicitly upload user video files and create sessions on https://mega-api-prod.nemovideo.ai — this is consistent with the purpose. However, the runtime steps tell the agent to generate or read a client_id in ~/.config/nemovideo/client_id and to build a claim URL that includes the auth token as a query parameter (https://nemovideo.com/workspace/claim?token=$TOKEN&...). Including tokens in URLs exposes them to browser history, logs, and referrers; this contradicts the SKILL.md line 'Don't expose tokens or raw API output' and is a privacy/security concern. The skill also requires detection of install path to set X-Skill-Platform which implies reading filesystem paths.

Install Mechanism

No install spec and no code files — the skill is instruction-only. That lowers code-execution risk because nothing is downloaded or written by an installer (aside from the normal runtime config write noted above).

Credentials

Only one credential is declared (NEMO_TOKEN), which is appropriate for talking to a remote API. But the manifest's required-env status conflicts with the described behavior to auto-obtain an anonymous NEMO_TOKEN if none is present. Also, the skill writes/reads ~/.config/nemovideo/client_id (declared in metadata), which is proportional but worth noting because it persists identity on disk.

Persistence & Privilege

always is false and the skill doesn't request system-wide privileges. The only persistent action described is writing a client_id to ~/.config/nemovideo/, which is consistent with maintaining an anonymous client identity rather than a privilege escalation attempt.

What to consider before installing

This skill does what it claims — it uploads video files to a NemoVideo backend and returns audio — but take these precautions before using it: 1) Expect your video (and its audio) to leave your machine and be stored/processed by nemovideo.com; do not upload sensitive material unless you trust their policies. 2) The skill may create and store a client_id under ~/.config/nemovideo/ and can auto-generate an anonymous NEMO_TOKEN; if you prefer control, supply your own NEMO_TOKEN rather than letting the skill obtain one. 3) The skill builds a 'claim' link that embeds the token in the URL query string — this can leak the token via logs, history, or referrers. Ask the provider or avoid using that link with sensitive tokens. 4) The manifest and SKILL.md disagree about whether NEMO_TOKEN is strictly required; clarify whether you must supply credentials. If you need lower risk, only use with non-sensitive videos or request clearer token-handling behavior from the skill author.

Getting Started

Welcome! Ready to pull the audio out of your video file? Drop your mp4, mov, avi, webm, or mkv and tell me what you need — let's get your audio extracted right now.

Try saying:

• "Extract the audio from this mp4 interview recording and give it back as a clean audio file"
• "I have a webm lecture video — can you strip out just the audio so I can listen offline?"
• "Convert this mov file from my camera into audio only, I need it for my podcast episode"

Quick Start Setup

This skill connects to NemoVideo's cloud backend. On first use, set up the connection automatically and let the user know ("Connecting to NemoVideo...").

Token check: Look for NEMO_TOKEN in the environment. If found, skip to session creation. Otherwise:

• Read ~/.config/nemovideo/client_id or generate a UUID and save it there
• POST https://mega-api-prod.nemovideo.ai/api/auth/anonymous-token with X-Client-Id header
• Extract data.token from the response — this is your NEMO_TOKEN (100 free credits, 7-day expiry)

Session: POST /api/tasks/me/with-session/nemo_agent at the same host with Bearer auth and body {"task_name":"project"}. Keep the returned session_id for all operations.

Let the user know with a brief "Ready!" when setup is complete. Don't expose tokens or raw API output.

Turn Any Video Into Pure Audio Instantly

Sometimes the video is just a container for what really matters — the voice, the music, the conversation. This skill exists for exactly those moments. Whether you recorded a lecture on your phone, captured a live performance on a camera, or downloaded a webinar you need to review on your commute, the video-to-audio-converter skill strips away the visual layer and hands you back the audio in a clean, usable format.

You don't need to open a timeline editor, install a plugin, or remember a command-line flag. Just bring your file — mp4, mov, avi, webm, or mkv — describe what you want, and the skill handles the extraction. The result is audio that's ready to drop into a podcast editor, share with a collaborator, or archive alongside your notes.

This skill is especially useful for content creators who batch-produce video but distribute across audio platforms, researchers who record interviews on video for reference but transcribe from audio, and educators who want to make recorded lessons accessible to learners in audio-only formats. It fits into your existing workflow without asking you to change it.

Routing Your Conversion Requests

Each request — whether you're stripping audio from an MP4, pulling a clean WAV from an MKV, or batch-extracting tracks — is routed to the appropriate NemoVideo extraction pipeline based on the source container format and your specified output codec.

User says...	Action	Skip SSE?
"export" / "导出" / "download" / "send me the video"	→ §3.5 Export	✅
"credits" / "积分" / "balance" / "余额"	→ §3.3 Credits	✅
"status" / "状态" / "show tracks"	→ §3.4 State	✅
"upload" / "上传" / user sends file	→ §3.2 Upload	✅
Everything else (generate, edit, add BGM…)	→ §3.1 SSE	❌

NemoVideo API Reference

The NemoVideo backend handles demuxing and audio stream isolation server-side, supporting lossless extraction as well as transcoded outputs like MP3, AAC, FLAC, and OGG without re-encoding the video track. Bitrate preservation, channel mapping, and sample rate targeting are all passed as parameters through the API call.

Skill attribution — read from this file's YAML frontmatter at runtime:

• X-Skill-Source: video-to-audio-converter
• X-Skill-Version: from frontmatter version
• X-Skill-Platform: detect from install path (~/.clawhub/ → clawhub, ~/.cursor/skills/ → cursor, else unknown)

All requests must include: Authorization: Bearer <NEMO_TOKEN>, X-Skill-Source, X-Skill-Version, X-Skill-Platform. Missing attribution headers will cause export to fail with 402.

API base: https://mega-api-prod.nemovideo.ai

Create session: POST /api/tasks/me/with-session/nemo_agent — body {"task_name":"project","language":"<lang>"} — returns task_id, session_id. After creating a session, give the user a link: https://nemovideo.com/workspace/claim?token=$TOKEN&task=<task_id>&session=<session_id>&skill_name=video-to-audio-converter&skill_version=1.0.0&skill_source=<platform>

Send message (SSE): POST /run_sse — body {"app_name":"nemo_agent","user_id":"me","session_id":"<sid>","new_message":{"parts":[{"text":"<msg>"}]}} with Accept: text/event-stream. Max timeout: 15 minutes.

Upload: POST /api/upload-video/nemo_agent/me/<sid> — file: multipart -F "files=@/path", or URL: {"urls":["<url>"],"source_type":"url"}

Credits: GET /api/credits/balance/simple — returns available, frozen, total

Session state: GET /api/state/nemo_agent/me/<sid>/latest — key fields: data.state.draft, data.state.video_infos, data.state.generated_media

Export (free, no credits): POST /api/render/proxy/lambda — body {"id":"render_<ts>","sessionId":"<sid>","draft":<json>,"output":{"format":"mp4","quality":"high"}}. Poll GET /api/render/proxy/lambda/<id> every 30s until status = completed. Download URL at output.url.

Supported formats: mp4, mov, avi, webm, mkv, jpg, png, gif, webp, mp3, wav, m4a, aac.

SSE Event Handling

Event	Action
Text response	Apply GUI translation (§4), present to user
Tool call/result	Process internally, don't forward
heartbeat / empty data:	Keep waiting. Every 2 min: "⏳ Still working..."
Stream closes	Process final response

~30% of editing operations return no text in the SSE stream. When this happens: poll session state to verify the edit was applied, then summarize changes to the user.

Backend Response Translation

The backend assumes a GUI exists. Translate these into API actions:

Backend says	You do
"click [button]" / "点击"	Execute via API
"open [panel]" / "打开"	Query session state
"drag/drop" / "拖拽"	Send edit via SSE
"preview in timeline"	Show track summary
"Export button" / "导出"	Execute export workflow

Draft field mapping: t=tracks, tt=track type (0=video, 1=audio, 7=text), sg=segments, d=duration(ms), m=metadata.

Timeline (3 tracks): 1. Video: city timelapse (0-10s) 2. BGM: Lo-fi (0-10s, 35%) 3. Title: "Urban Dreams" (0-3s)

Error Handling

Code	Meaning	Action
0	Success	Continue
1001	Bad/expired token	Re-auth via anonymous-token (tokens expire after 7 days)
1002	Session not found	New session §3.0
2001	No credits	Anonymous: show registration URL with ?bind=<id> (get <id> from create-session or state response when needed). Registered: "Top up at nemovideo.ai"
4001	Unsupported file	Show supported formats
4002	File too large	Suggest compress/trim
400	Missing X-Client-Id	Generate Client-Id and retry (see §1)
402	Free plan export blocked	Subscription tier issue, NOT credits. "Register at nemovideo.ai to unlock export."
429	Rate limit (1 token/client/7 days)	Retry in 30s once

Performance Notes

Extraction speed depends primarily on the length and bitrate of the source video. Short clips under ten minutes process quickly, while longer files — full-length webinars, feature-length recordings — will take proportionally more time. The skill prioritizes audio fidelity, so the extracted track reflects the quality of the original recording rather than introducing compression artifacts.

For best results, use source files with a consistent, clean audio track. Videos with highly variable audio levels, multiple embedded audio streams, or corrupted segments may produce output that requires further editing. If your video contains multiple audio tracks (common in mkv files from screen recorders or multi-language sources), specify which track you want extracted to avoid ambiguity.

Supported input formats are mp4, mov, avi, webm, and mkv. Files outside these formats will need to be converted before the skill can process them.

Quick Start Guide

Getting started is straightforward. Have your video file ready — mp4, mov, avi, webm, or mkv all work without any preparation on your end. Open the skill and describe your request naturally: mention the file, what you want done, and any preferences about the output if you have them.

If you're not sure what to say, a simple prompt like 'extract the audio from this video file' is enough to get the process moving. You can also specify preferences such as asking for a particular segment of the video rather than the full duration, or noting that you want the audio at its original quality rather than compressed.

Once extraction is complete, you'll receive your audio file ready for download. From there it's yours to edit, share, transcribe, or archive — no further steps required on this end. If the first result isn't quite right, just describe the adjustment and the skill will handle it.

Common Workflows

The most frequent use case is podcast production: a host records a conversation over video call, then needs to strip the visual track before editing in their audio software. With this skill, that step takes seconds instead of requiring a separate app.

Another popular workflow is lecture archiving. Educators and students who record class sessions on video often want a lightweight audio version for review or transcription. Upload the mkv or mp4, extract the audio, and feed it directly into a transcription tool or media player.

Musicians and sound designers also rely on this skill to isolate recorded performances. If a live set was captured on video, the audio extraction gives them a working file they can bring into a DAW without any manual re-routing. The skill handles avi and mov formats commonly produced by cameras and recording rigs, making it practical for field recordings and live event capture as well.