OpenRouter key credit limit and 402 vs a Sume per-run spend cap

OpenRouter puts the limit on the key: it can hold a credit limit that resets on a schedule, and spending past it returns a 402. A Sume Format run puts a limit on each run with generation_spend_cap_usd, so one runaway call cannot use the whole budget. They guard different things, and an unattended job benefits from both.

What does OpenRouter's page say?

The limits reference describes per-key limits and how to read them.

What is Sume's equivalent?

Sume sets the ceiling per run. generation_spend_cap_usd can go up to $500. If you leave it out, the Format's own cap applies, which defaults to $400. Sending null means $500, and 0 or any value above 500 is a 400. A run that reaches its cap ends failed, and the generation it finished is billed.

The receipt reports usage.billable_amount_usd_micros and usage.generation_spend_cap_usd_micros, so you can see how close a run came.

Does Sume have a per-key limit?

I did not find a per-key credit limit with a reset schedule in the Sume docs, so do not assume one. What exists is the wallet: a create call returns 402 insufficient_credits when the balance cannot cover it, and nothing runs. For a Scheduled agent, the default cap is $1.00 per run, and a per-run override can only lower it.

• Use the OpenRouter key limit when many callers share one key and you want a rolling budget.
• Use the Sume per-run cap when one call must never exceed a number.
• Set both, and alert on the 402, since either one means work stopped.

Where to read next

The spend caps section has the exact semantics, and the credits and spend errors list what each code means.