ElevenLabs Music v2.5 plan limits vs Sume's 5000-character prompt

The ElevenLabs changelog for September 14, 2026 says music endpoints and SDKs now accept music_v2_5, and that composition plan chunks support up to 6,132 characters, with up to 30 lines of 200 characters each. Sume's Music Router takes a single prompt of 1 to 5000 characters and rejects duration and duration_seconds, so structure goes inside the prompt as section markers such as [0:00-0:30] Intro: ....

Sources: the ElevenLabs changelog and Sume's Music Router docs, read 2026-10-01.

What are the plan limits?

How do I turn a 30-line plan into a Sume prompt?

Treat each plan line as one timed section marker. A plan with an intro, a build, a drop and an outro becomes four lines such as [0:00-0:30] Intro: ..., [0:30-1:00] Build: .... The Music 1.0 docs show markers in this form and also a prompt that names a moment at 0:12. Exclusions go in the positive text, because a non-empty negative_prompt is unsupported.

Why does Sume reject duration?

Both Sume music pages say length is steered in the prompt, for example "a 2-minute track". Music 1.0 has no seed, temperature, guidance or duration parameter, and the Router rejects duration and duration_seconds. The practical effect: you cannot ask for an exact length, only describe one. For exact-length edits see music for one section.

What does a Sume music call cost?

The rate card lists music generation at $0.125 per audio, regardless of prompt length. Compare plan approaches in composition plan versus prompt only.