Add subtitles to video | agent view
The same page content and links, with explicit tool capabilities. Tools marked with an API can run directly through HTTP. Other tools require the browser interface or are not connected yet.
Tool capabilities
{
"id": "add-subtitles-to-video",
"category": "media-tools",
"built": true,
"requirements": "Separate soft-track muxing from hardcoded captions; font and layout tests.",
"implementation": {
"fields": [
{
"key": "engine",
"label": "Processing location",
"type": "select",
"value": "browser",
"values": [
"browser",
"server"
],
"labels": {
"browser": "Browser (files stay here)",
"server": "Local server (larger files)"
}
}
],
"files": true,
"accept": ".mp4,.mov,.mkv,.webm,.avi,.srt",
"multiple": true,
"input": false,
"processing": "Browser or server",
"native": true,
"maxFileBytes": 20971520,
"note": "Browser processing keeps files on this device. Choosing Local server sends files to this website’s own processor. Choose one video and one SRT file. Adds a selectable subtitle track to MP4; subtitles are not burned into the picture.",
"hybrid": true,
"experience": {
"automatic": false,
"single": false,
"label": "Your text",
"placeholder": "Type or paste your input…",
"help": "Up to 1,000,000 characters. Review the settings before running.",
"action": "Convert file"
},
"mode": "explicit",
"interactive": false
},
"execution": "POST /api/v1/tools/add-subtitles-to-video/run",
"api": {
"id": "add-subtitles-to-video",
"name": "Add subtitles to video",
"category": "media-tools",
"description": "Add an SRT subtitle track to a video.",
"notes": "Browser processing keeps files on this device. Choosing Local server sends files to this website’s own processor. Choose one video and one SRT file. Adds a selectable subtitle track to MP4; subtitles are not burned into the picture.",
"human_path": "/en/media-tools/add-subtitles-to-video/",
"method": "POST",
"endpoint": "/api/v1/tools/add-subtitles-to-video/run",
"schema_url": "/api/v1/tools/add-subtitles-to-video",
"input_schema": {
"type": "object",
"additionalProperties": false,
"properties": {
"input": {
"type": "string",
"maxLength": 1000000,
"default": "",
"description": "Plain text input. File tools use files instead unless otherwise documented."
},
"options": {
"type": "object",
"additionalProperties": false,
"properties": {
"engine": {
"type": "string",
"description": "Processing location",
"default": "browser",
"enum": [
"browser",
"server"
]
}
}
},
"files": {
"type": "array",
"maxItems": 20,
"items": {
"type": "object",
"required": [
"name",
"base64"
],
"additionalProperties": false,
"properties": {
"name": {
"type": "string",
"maxLength": 200,
"description": "Filename only, no path."
},
"mime": {
"type": "string",
"maxLength": 150
},
"bytes": {
"type": "integer",
"minimum": 0,
"description": "Optional decoded byte count; must match content if supplied."
},
"base64": {
"type": "string",
"contentEncoding": "base64",
"description": "File bytes as padded base64. Use the tool-specific limits.files_bytes value for the total decoded input size."
}
}
}
}
}
},
"output_schema": {
"type": "object",
"required": [
"tool",
"result"
],
"properties": {
"tool": {
"type": "string"
},
"result": {
"type": "object",
"required": [
"text",
"files"
],
"properties": {
"text": {
"type": [
"string",
"null"
]
},
"data": {
"description": "Parsed JSON when the textual result is JSON."
},
"name": {
"type": "string"
},
"mime": {
"type": "string"
},
"files": {
"type": "array",
"items": {
"type": "object",
"required": [
"name",
"mime",
"bytes",
"base64"
],
"properties": {
"name": {
"type": "string"
},
"mime": {
"type": "string"
},
"bytes": {
"type": "integer"
},
"base64": {
"type": "string",
"contentEncoding": "base64"
}
}
}
}
}
}
}
},
"processing": "Server; self-hosted native engine, no external conversion service",
"limits": {
"request_bytes": 31457280,
"input_characters": 1000000,
"files_bytes": 20971520,
"max_files": 20,
"timeout_seconds": 90
}
},
"agent_processing": "Server; self-hosted native engine, no external conversion service",
"browser_agent": {
"supported": true,
"name": "run_current_tool",
"discovery": "WebMCP on the human page in a supporting browser",
"verification": "See audit/API-AUDIT.md; availability is not verification"
}
}Page guide
Add an SRT subtitle track to a video.
Useful next steps
How to use Add subtitles to video
- Choose one or more files in MP4, MOV, MKV, WEBM, AVI or SRT.
- Review the settings, then choose Convert file.
- Review the result, then use Copy result or a download link when available.
What to expect
Add an SRT subtitle track to a video. Browser processing keeps files on this device. Choosing Local server sends files to this website’s own processor. Choose one video and one SRT file. Adds a selectable subtitle track to MP4; subtitles are not burned into the picture.