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Change video speed | 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": "change-video-speed",
  "category": "media-tools",
  "built": true,
  "requirements": "Video/audio timebase alignment and pitch behavior; preview duration.",
  "implementation": {
    "fields": [
      {
        "key": "speed",
        "label": "Speed multiplier",
        "value": 1.25,
        "type": "number",
        "min": 0.5,
        "max": 2,
        "step": "any"
      },
      {
        "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",
    "multiple": false,
    "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. Adjusts video timing and audio speed together, preserving audio pitch.",
    "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": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "POST /api/v1/tools/change-video-speed/run",
  "api": {
    "id": "change-video-speed",
    "name": "Change video speed",
    "category": "media-tools",
    "description": "Speed up or slow down a video and its audio.",
    "notes": "Browser processing keeps files on this device. Choosing Local server sends files to this website’s own processor. Adjusts video timing and audio speed together, preserving audio pitch.",
    "human_path": "/en/media-tools/change-video-speed/",
    "method": "POST",
    "endpoint": "/api/v1/tools/change-video-speed/run",
    "schema_url": "/api/v1/tools/change-video-speed",
    "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": {
            "speed": {
              "type": "number",
              "description": "Speed multiplier",
              "default": 1.25,
              "minimum": 0.5,
              "maximum": 2
            },
            "engine": {
              "type": "string",
              "description": "Processing location",
              "default": "browser",
              "enum": [
                "browser",
                "server"
              ]
            }
          }
        },
        "files": {
          "type": "array",
          "maxItems": 1,
          "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": 1,
      "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

Speed up or slow down a video and its audio.

Useful next steps

How to use Change video speed

  1. Choose a file in MP4, MOV, MKV, WEBM or AVI.
  2. Review the settings, then choose Run Change video speed.
  3. Review the result, then use Copy result or a download link when available.

What to expect

Speed up or slow down a video and its audio. Browser processing keeps files on this device. Choosing Local server sends files to this website’s own processor. Adjusts video timing and audio speed together, preserving audio pitch.