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The Voice primitive lets an agent speak in a cloned voice it is authorized to use, and lets a human create and manage those voices under an explicit consent record. On top of it, the digital-twin clone turns a reference image + a cloned voice + a script into a lip-synced talking video. There are two surfaces with deliberately different trust levels:
  • Agent surface (API key): synthesize speech in a voice the agent already owns, list voices, generate talking videos.
  • Human surface (signed-in session): create (clone) and revoke voices. These record a legal consent affirmation, so they require a human session — not just an API key.
Cloning and revoking a voice are human-only. Run naive auth session-login first (see Authentication). Synthesis and talking-video generation work with a normal agent API key.

Cloning a voice (human-only)

Arguments: Key options: For third-party voices the consenter receives a verification link; the voice stays in a draft/pending state until consent is confirmed. authorized_uses is enforced at synthesis time — a voice cloned for email only will refuse a video use.

Revoking a voice (human-only, irreversible)

This irreversibly erases the voice and its underlying audio, and marks the consent record revoked. Any later synthesis attempt returns voice_revoked.

Synthesizing speech (agent surface)

REST:
The use field must fall within the voice’s authorized_uses. Text is capped at 5000 characters per call. The audio URL is presigned and expires after 24 hours — re-run say if it lapses.

Digital twin — talking video

naive clone generate produces a lip-synced talking video of a real person from a reference image, an existing cloned voice, and a script. The voice supplies both the audio and the consent record; the image supplies the likeness (which you must separately affirm).
REST:
Generation is async and runs through the unified jobs system; the finished video is auto-ingested into your Media Asset Manager. Every voice is backed by a consent record that captures who consented, the affirmation text, and the authorized uses. This is enforced end to end:
  • Cloning requires --i-affirm and a consent_type; third-party voices require the consenter’s verification.
  • Synthesis and talking-video generation are refused if the voice was revoked (voice_revoked) or the declared use is outside the authorized set.
  • The digital-twin clone additionally requires an explicit likeness affirmation for the depicted person.

Billing

  • Synthesis is billed per character of input text at 0.0025 credits/character — $0.125 per 1,000 characters, or about 0.3 credits for a 120-word paragraph. The exact charge is returned as credits on each say, and streaming (/v1/voice/stream) is billed at the same rate as /v1/voice/synthesize.
  • Talking-video generation is billed on completion like other video jobs — failed jobs cost nothing.
  • Cloning and revoking voices are free; you pay only when you synthesize or generate.
Account Kits can enable/disable the voice primitive per user, and the human-only clone/revoke surface is always gated behind a signed-in session.