Preprint · Solana · October 2026 · launching on Meteora

Keep the Stock, Spend the Interest

Interest-funded AI on Solana

Prism$PRISM · NOTE

drag the prism

GPT-5.5 Pro$30.00/M
GPT-5.5$5.00/M
Claude Sonnet 5.5$2.00/M
Gemini 4 Argon$2.00/M
DeepSeek V4.1 Flash$0.15/M
Claude Haiku 5.5$0.10/M

Figure 1: Interest as light. A beam of interest enters the prism once a slot (about 0.4 s); the prism, Auto routing, spreads it across models by price, and simple work goes to the cheapest model that can do it (blue). Each label is a live price per million input tokens. Kamino read at 17:19 UTC; model prices at 17:11 UTC.

Abstract

Tokenized stocks earn nothing while they sit in a wallet, and AI is billed by the token. We describe Prism, vaults on Solana that lend a deposit through Kamino [1] and turn the interest into NOTE, a token backed one-to-one by USDC that pays for model calls. Dollars earn 4.53%. NVDAx, SPYx and QQQx earn 0.71% of their value, by borrowing PYUSD at 0.85% against 30% of it and lending that at 3.24%; the stock is never sold. At today's prices, $10,000 in USDC pays for about 94k requests a month to Claude Haiku 5.5. Holding $PRISM turns on Auto routing, which sends each request to the cheapest model that can do it. Every number in this paper is read live; none is a projection.

Keywords: tokenized stocks, lending, AI credits, routing, Solana

1Introduction

Someone who holds an index fund and uses AI every day pays for the AI twice: once with money that is already invested, and again with a subscription. On Solana, stocks now live in the same kind of wallet as money. xStocks are SPL tokens [5], and Kamino accepts them as collateral in isolated markets [1]. A deposit can therefore earn interest without being sold, and the interest can be spent.

Prism does exactly that, and no more. This paper makes three small, practical contributions: a vault for dollars and one for stocks, each with a single rate that can be read from Kamino at any slot (Section 2); a credit, NOTE, that turns the interest into model calls (Section 2.3); and a router for $PRISM holders (Section 5).

2Mechanism

2.1Dollars

USDC is lent in Kamino's main market. Its rate is the market's supply rate:

r_{$} = r_{USDC}^{main} = 4.53% (1)

2.2Stocks

¹ Kamino's Sentora xStocks market is isolated: trouble in one stock cannot spread to another.A stock vault keeps the stock as collateral in Kamino's Sentora xStocks market,¹ borrows PYUSD worth a fraction β = 0.30 of the stock's value, and lends that PYUSD in the main market. The stock earns the spread on the borrowed fraction:

r_{S} = β (r_{PYUSD}^{main} - r_{PYUSD}^{xs}) = 0.30 \times (3.24% - 0.85%) = 0.71% (2)

The loan stays far from its limit. With a maximum loan-to-value λ (70% for QQQx), the stock can fall by

Δ_{m a x} = 1 - \frac{β}{λ} = 1 - \frac{0.30}{0.70} = 57% (3)

before the loan reaches it, and the vault repays early well before that. Stocks whose dollars would cost more to borrow than they earn, so that r_S < 0, are not opened. Table 1 gives every vault as it stands.

**Table 1:** Vaults on Kamino, read at 17:19 UTC. A stock vault borrows PYUSD worth β = 0.30 of the stock's value; r is Eq. (1) for dollars and Eq. (2) for stocks.
Vault	Price	Lent at	Borrowed at	Room	r	NOTE / yr per $1k
USDCdollars	$1.00	4.53%	—	—	4.53%	$45.25
QQQxNasdaq 100	$718.40	3.24%	0.85%	$9.7M	0.71%	$7.14
NVDAxNVIDIA	$216.85	3.24%	0.85%	$9.7M	0.71%	$7.14
SPYxS&P 500	$768.76	3.24%	0.85%	$9.7M	0.71%	$7.14

Not opened, because borrowing against them costs more than lending earns (r_S < 0): HOODx, GOOGLx, CRCLx, TSLAx, METAx, AAPLx, MSTRx (−2.45 pp).

2.3Credits

Interest accrues every slot. A keeper collects it and mints NOTE against a deposit D at rate r:

N_{t} = s \leq t \sum D r Δ t_{s}, 1 NOTE \equiv 1 USDC (4)

NOTE is backed by USDC held onchain. It can be held, sent to another wallet or to an agent, spent on any model, or redeemed.

3What a deposit buys

A request of 1,500 input and 500 output tokens to a model m, priced pⁱⁿ and p^out per million tokens[3], costs c(m); a month of interest therefore pays for

n (m) = \frac{D r /12}{c ( m )}, c (m) = \frac{1 , 500 p _{m}^{in} + 500 p _{m}^{out}}{1 0 ^{6}} (5)

requests. Figure 2 sets Eq. (5) with your own numbers.

Vault

Deposit DUSDC

USDC is lent at r = 4.53%, Eq. (1).

D r / 12, in NOTE a month$452.53 a year

$37.71a month

Model m	tier	n(m) / mo
Claude Haiku 5.5$0.10 / $0.50	fast	94k
Grok 4.7$2.00 / $6.00	smart	6,285
Claude Opus 5.5$4.00 / $20.00	frontier	2,357

Figure 2: What a deposit buys, Eq. (5), with your own numbers. Rates are Kamino's and prices OpenRouter's, both read live; a request is 1,500 tokens in and 500 out. The deposit itself is never spent.

4From a share to a model

Figure 3 follows one deposit through Eqs. (2) and (4) to a model. Scroll, and it is drawn.

Figure 3a: The deposit. NVDAx, SPYx, QQQx or USDC go into a vault of your own on Solana; nothing is sold, and only your wallet can take it out.

Figure 3b: A small loan. The vault borrows PYUSD worth β = 0.30 of the stock's value in Kamino's isolated xStocks market, at 0.85%, far under the 70% limit.

Figure 3c: The dollars work. The PYUSD is lent in Kamino's main market at 3.24%; the gap is your interest, 0.71% of the stock a year. USDC skips the loan and earns 4.53%.

Figure 3d: Interest becomes NOTE, Eq. (4): one per dollar, each backed by a dollar of USDC held onchain. Hold it, send it, or spend it.

Figure 3e: NOTE pays for 336 models through one key; $PRISM holders route each request to the cheapest model that can do it (Section 5).

5Routing

Wallets that hold $PRISM (1,000 or more) get Auto routing: each request goes to the cheapest model that can do it. Nothing is staked and there is nothing to sign up for; Prism reads the balance when the wallet signs in. The saving on a request moved from model a to model b is

s (a \to b) = 1 - \frac{c ( b )}{c ( a )} (6)

and Table 2 prices three such moves at today's prices.

**Table 2:** Example routes at today's prices, with c from Eq. (5) and s from Eq. (6). The router decides per request; the rows show the size of the difference, not a promise.
Request	Default a	c(a)	Routed b	c(b)	s
Summarize an email	Claude Sonnet 5.5	$0.0080	Claude Haiku 5.5	$0.0004	−95%
Review a pull request	Claude Opus 5.5	$0.0160	Claude Sonnet 5.5	$0.0080	−50%
Draft a reply	GPT-5.5	$0.0225	DeepSeek V4.1 Flash	$0.0005	−98%

6Properties of the vault

The following are requirements of the vault's design. At launch each one is a property of the deployed program and can be checked onchain by anyone; until then they are what it is built to.

Property 1 (Withdrawal). At any slot the depositor can withdraw the whole deposit. There is no lockup and no notice period.

Property 2 (Ownership). The vault has no function that moves a deposit anywhere but back to its depositor.

Property 3 (Notice). A move to a different Kamino market is announced onchain days ahead, so anyone can leave first.

Property 4 (Isolation). Each stock is lent in an isolated market; a failure in one does not reach the others.

Property 5 (Margin). A stock vault borrows β = 0.30 of the stock's value and repays early as the loan grows; by Eq. (3) the stock can fall about 57% before the loan reaches its limit.

Property 6 (Backing). Every NOTE in circulation has one USDC behind it, held onchain.

7Interface

The API speaks the OpenAI chat format, so existing clients only change the address and the key. Listing 1 routes a call with model="auto".

from openai import OpenAI

client = OpenAI(base_url=PRISM_BASE_URL, api_key=PRISM_KEY)

reply = client.chat.completions.create(
    model="auto",                      # Section 5
    messages=[{"role": "user", "content": "Summarize my portfolio news"}],
)

Listing 1: A call paid from interest. Streaming, tools and JSON mode work as usual.

8Limitations

The vault and Kamino are smart contracts; both carry the risk of a bug.
Rates move with demand and can fall to zero; Eq. (2) is negative for some stocks today, which is why they are not opened.
xStocks carry issuer controls, such as freezing and pausing, that no vault can remove [5].
NOTE is worth a dollar because USDC is; it carries USDC's risks.
Tokenized stocks are not available in every country.

Run Figure 2 with your deposit Read the mechanism again

References

[1]Kamino Finance. Kamino Lend: lending markets and reserves. api.kamino.finance, read live.
[2]Jupiter. Price API v3. lite-api.jup.ag, read live.
[3]OpenRouter. Models API. openrouter.ai/api/v1/models, read live.
[4]Meteora. Dynamic Bonding Curve. meteora.ag.
[5]Backed. xStocks: tokenized equities on Solana. xstocks.com.

AQuestions

What can I deposit?

USDC, and the tokenized stocks that Kamino lends against with a positive spread today: NVDAx, SPYx and QQQx. Other xStocks open when borrowing against them costs less than lending earns; Table 1 shows which.

Do I still own my shares?

Yes. The stock sits in a vault that only your wallet can withdraw from. It is never sold; it is collateral for a loan of 30% of its value.

What happens to NOTE I do not use?

It stays yours. NOTE is a token backed 1:1 by USDC: keep it, send it to another wallet or to an agent, or redeem it.

What does $PRISM do?

Holding 1,000 $PRISM turns on Auto routing (Section 5). It launches on Meteora.

Is this investment advice?

No. This page describes a mechanism and reads public rates. Rates change with demand and nothing here is a promise of return.

BCiting this paper

@misc{prism2026,
  title  = {Keep the Stock, Spend the Interest:
            Interest-Funded {AI} on Solana},
  author = {Prism},
  year   = {2026},
  month  = oct,
  note   = {Preprint, v1}
}