A run, within its limits

sion agent run puts an agent identity to work: a language model plans and calls tools, and the runtime runs each call under rules you set. The ledger is one of its tools, and the agent’s charter is the limit no runtime setting can loosen: a payment outside it is refused by the validators, whatever the runtime allowed.

Outputs on this page are from real runs on a local devnet, long identifiers shortened with …. The model is a scripted one, which plays a fixed list of tool calls, because the environment these pages were made in reaches no model provider: with a real model the runtime is the same, and only --model changes.

An agent and its limits

alice registers agent-7: it may pay only bob, at most 10 USD a payment and 50 USD at once, its bucket refilled by 0.05 USD a Pulse, from a budget of 100 USD. The agent’s account pays its transactions’ fees, so it gets 1 USD for them:

$ sion agent register alice agent-7 --payees bob --max-payment 10 --burst 50 --rate 0.05 --funding 100
alice signs: Register agent-7 as an agent, funded with 100 USD: only to bob, at most 10 USD per payment, 50 USD at once, refilled by 0.05 USD a Pulse, until Pulse 100000, a receipt claim for every payment, may delegate narrower limits. Fee 0.0011 USD; valid until Pulse 20.
Pulse 2: Done: agent bdbdb742 registered, signing as agent-7; fee 0.0011 USD.
agent bdbdb742f506a53671928c83efc1c57321d70dd0636d84ab873575f9f70f60df
…
$ sion faucet agent-7 1

A run

The script checks the agent’s budget, pays bob, then tries two payments its charter forbids: a tip to carol, and 50 USD to bob. At autonomy L6 the runtime lets every call through, so the ledger is what refuses them:

$ sion agent run agent-7 bdbdb742…60df --task 'Pay bob 5 USD for inference.' --model script:pay.json --autonomy L6
session 4c16d4afda9b2fc7 for agent bdbdb742
  → ledger_balance {}
  ← {"budget_remaining_usd":"100","burst_usd":"50","can_spend_now_usd":"50","expires_at_pulse":100000,"fee_balance_usd":"1","max_per_payment_usd":"10","payees":["bob"],"refill_usd_per_pulse":"0.05","status":"active"}
  → ledger_pay {"amount":"5","purpose":"inference","to":"bob"}
  ← Pulse 7: Done: agent paid 5 USD to bob (receipt claim 60bed29d); fee 0.0012 USD. Transaction ef8072e0….
  → ledger_pay {"amount":"5","purpose":"a tip","to":"carol"}
  ✗ refused by the ledger at Pulse 9: Failed (charter caveat violated: payee not allowed); nothing happened except the fee of 0.0011 USD.
  → ledger_pay {"amount":"50","purpose":"a big order","to":"bob"}
  ✗ refused by the ledger at Pulse 12: Failed (charter caveat violated: payment 50 above per-payment limit 10); nothing happened except the fee of 0.0011 USD.
agent: Paid bob 5 USD for inference. The ledger refused a tip to carol, who is not a payee my charter allows, and a 50 USD order, above my 10 USD limit per payment.
session 4c16d4afda9b2fc7: done

A script is a JSON array of steps: {"call": "<tool>", "input": {…}}, {"calls": [ … ]} for several calls in one turn, and {"say": "…"} to finish. The agent’s tools: