For the human who owns the funds
Connect Phantom, set the rules, watch spend, revoke in one click. You are the primary user — not the merchant, not the model.
Squads for AI agents · Solana Devnet
Your agent can pay. It cannot empty the wallet.
Reins is spend control for AI agents. You set a budget, a merchant list, and an expiry on-chain. The model pays APIs. A jailbreak cannot break those reins.
Phantom on Devnet · demo ticker CSO · no real money
Agents should not hold the whole wallet
Today a team that lets Claude or Cursor pay APIs either pastes a hot key, hardcodes a cap in app code, or trusts a facilitator with no merchant list. Prompt injection can drain the account or pay an attacker. Reins puts the limit in a Solana program the model cannot talk past.
For the agent that pays
CLI or Cursor MCP (reins-spend-mcp) calls spend under that policy. In-budget merchant pays go through. Over-budget and wrong payee come back as program rejects.
What you do in the app
Same path a judge or teammate should finish in a few minutes on Devnet.
- 1
Connect Phantom on Devnet
Open the app, connect the wallet that owns the funds. That wallet is the root — it holds the reins.
- 2
Claim test CSO & set policy
Faucet drips demo tokens. Create an agent, set a budget, pick allowed merchants, optionally set expiry.
- 3
Pay in-policy, fail out-of-policy
A small merchant pay succeeds. Over-budget and wrong-payee fail. Revoke, then spend fails again.
The program holds the reins
Not a new chain and not another payment facilitator. Reins is the control plane: policy lives on Solana; merchants check a real spend receipt.
Budget
You cap how much the agent can spend. Over-budget payments revert on-chain — even if the model is jailbroken.
Allowlist
Only merchants you name can be paid. A wrong payee is rejected by the program, not by a prompt.
Expiry & revoke
Set a deadline. One revoke transaction stops spend immediately. Leftover funds stay in your vault.
Live on Solana Devnet
Public surfaces for the product — ticker on-chain is still CSO.
- MCP / CLI — let a model spend under policy, no UI click. npmjs.com/package/reins-spend-mcp
- App — Phantom console: faucet, policy, pay, revoke. reins-app.vercel.app/agents
- Merchant — paid infer after an on-chain spend. reins-merchant.vercel.app
- Faucet API — Devnet CSO drip for the app. reins-api.vercel.app
- Program —
cso_agenton Explorer. View on Solana Devnet
Set the reins. Then let the agent pay.
Connect → faucet → budget + allowlist → pay OK → over-budget fail → revoke.