9 paid Sume MCP tools and what each charges, from RMBG to music

Sume's hosted MCP server lists nine paid tools: generate_image, generate_video, music_create, tts_create, stt_create, image_upscale_create, rmbg_create, video_upscale_create and kling-motion-control_create. Each call that creates paid work carries an idempotency_key, and if you omit payload.model the call routes to sume/auto unless the user named a family. Seven of the nine have a fixed or per-unit price on the Sume price list; the two generation tools depend on the model you choose.

That matters for an agent budget. A flat-priced tool can be costed before the call, and a model tool needs a model id and options first.

The nine tools and their prices

Prices are from the lead-verified Sume price list (read 2026-10-08) and the hosted MCP tools-and-gates docs (read 2026-10-09).

Price an agent session

Take a session where an agent creates 3 images with Nano Banana 2.1 at 1K, cuts out 2 of them, upscales 1 and narrates a 600-character caption. The cost is 3 x $0.10 = $0.30 for the images, 2 x $0.0225 = $0.045 for cutouts, 1 x $0.20 = $0.20 for the upscale, and 0.6 x $0.0475 = $0.0285 for the narration. The total is $0.5735 before rounding up to the cent on each billed line.

The same session on the REST API costs the same, because the tools and the endpoints use the same price list. MCP adds the idempotency_key requirement and the OAuth consent flow, not a surcharge.

What the idempotency key protects

An agent can lose a response and retry. With a stable idempotency_key, a retry of the same operation should map to the same job, and Sume documents that a key reused for a different operation or payload returns a 409 idempotency_conflict. Build the key from the work: a SKU plus the tool name works for catalogs, and a thread id plus step number works for conversations.

Reads such as tts_source_get are free and need no key. The docs also list tools that are not on hosted MCP, including images_create and videos_create, which stay REST-only, so an agent that wants Image 1.0 behavior must call generate_image or use the Developer API.

• Name the model for generate_image if you need a predictable price
• Use one key per operation, never one key per session
• Check the 402 insufficient_credits case before long batches