> ## Documentation Index > Fetch the complete documentation index at: https://docs.eversince.ai/llms.txt > Use this file to discover all available pages before exploring further. # duck music > Lower the music under speech: every music clip ramps down just before the first word, holds, and ramps back after the last, with pauses under a second staying dipped. Speech is read from the words the clips carry (voiceover and dialogue, never lyrics); uploaded speech without word timing is listened to (a file too long for the call is queued and named in warnings). A muted video counts only through the audio detached from it. depth is a fraction of the music's level: soft to half, medium to a quarter (default), deep to a tenth. Every music clip that plays, or the ones named. Written as the clip's volume keyframes; setKeyframes on volume with an empty list removes it. Free, except listening to speech without word timing: cloud processing. ## OpenAPI ````yaml /openapi.json post /tools/duck_music openapi: 3.1.0 info: title: Eversince API version: '1' description: >- Every Eversince tool as one POST call, plus the routes beside them: the tool list, account and keys, uploads, webhooks and models. The prose is at https://docs.eversince.ai. servers: - url: https://eversince.ai/api/v1 security: - bearer: [] tags: - name: Discovery description: The tool list, the same on the MCP server, the REST API and the CLI. - name: Workspace description: Jobs, balances, settings, templates, skills and the overview. - name: Library description: >- Items, search, import, reading media, comments, boards, calendars, the brand kit and public links. - name: Timeline description: 'Video editing: timelines, clips, captions, sound, language and rendering.' - name: Canvas description: 'Still editing: canvases, slides, layers and rendering.' - name: Generation description: Image, video and audio generation, upscaling, cutouts and models. - name: Research description: 'What platforms publish: pulling and keeping posts.' - name: Account description: Balances, keys, workspaces and script sessions. - name: Uploads description: Files into the library by presigned upload or by URL. - name: Webhooks description: Job results posted to a URL as they complete. - name: Models description: Generation models and cost estimates. paths: /tools/duck_music: post: tags: - Timeline summary: duck music description: >- Lower the music under speech: every music clip ramps down just before the first word, holds, and ramps back after the last, with pauses under a second staying dipped. Speech is read from the words the clips carry (voiceover and dialogue, never lyrics); uploaded speech without word timing is listened to (a file too long for the call is queued and named in warnings). A muted video counts only through the audio detached from it. depth is a fraction of the music's level: soft to half, medium to a quarter (default), deep to a tenth. Every music clip that plays, or the ones named. Written as the clip's volume keyframes; setKeyframes on volume with an empty list removes it. Free, except listening to speech without word timing: cloud processing. operationId: duck_music parameters: - $ref: '#/components/parameters/IdempotencyKey' - $ref: '#/components/parameters/WorkspaceId' requestBody: required: true content: application/json: schema: type: object properties: timeline_id: type: string description: The timeline id. clip_ids: description: >- The music clips to duck. Absent: every music clip on the timeline that plays sound. type: array items: type: string depth: description: >- How far the music drops: soft to half its level, medium to a quarter (default), deep to a tenth. type: string enum: - soft - medium - deep if_revision: description: >- The revision get_timeline returned. A stale one fails with revision_conflict instead of applying; so does no revision once a user edited the timeline in the app since this connection last read it. anyOf: - type: string - type: integer context: description: 'Optional: one sentence shown to the user beside this action.' type: string maxLength: 600 required: - timeline_id responses: '200': description: >- Done, or a job started for work that runs longer (follow it with get_jobs). content: application/json: schema: type: object required: - ok - data - meta properties: ok: const: true data: type: object additionalProperties: true meta: type: object properties: request_id: type: string cost: $ref: '#/components/schemas/Cost' cloud_processing: $ref: '#/components/schemas/CloudProcessing' media: type: array items: type: object additionalProperties: true default: $ref: '#/components/responses/Error' components: parameters: IdempotencyKey: name: Idempotency-Key in: header required: false schema: type: string description: >- Retry a paid dispatch safely: the same key returns the job already dispatched instead of charging again. WorkspaceId: name: x-workspace-id in: header required: false schema: type: string description: The workspace this one call acts in, when it is not the key's own. schemas: Cost: type: object description: AI credits the call cost. additionalProperties: true CloudProcessing: type: object description: Cloud processing the call used, and what is left. properties: ran_on: const: cloud minutes: type: number queued_minutes: type: number left_minutes: type: number bought_minutes: type: number note: type: string Error: type: object required: - ok - error properties: ok: const: false error: type: object required: - code - message - retryable properties: code: type: string message: type: string description: What went wrong, in words to act on. retryable: type: boolean suggested_action: type: string description: The next step that works. cloud_processing: $ref: '#/components/schemas/CloudProcessing' responses: Error: description: The call was refused or failed. content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: bearer: type: http scheme: bearer description: >- An API key (es_live_…) from Settings, under API keys, or an OAuth access token. ````