Decrypt's article on Arc (Circle's stablecoin blockchain) is directly relevant to stablecoin settlement and USDC. It has a low 15% citation rate but a specific tag match. At $0.002, it's a cheap buy that could add unique insights on settlement infrastructure.

Web Payments Review covers x402 payment finalization times, relevant to settlement speed. It's cached, so free and could complement other sources.

Stablecoin Ledger's 'Why USDC settles instantly onchain' is a direct hit for the question title, with a 29% citation rate and a decent 0.81 avg weight. It's cached, so free to reuse—high value for zero cost.

Arc Settlement Benchmarks has a 15% citation rate and directly measures settlement latency on Arc, which could support sub-claims about instant finality. It's cached, so free to use.

Cointelegraph on Decta's stablecoin treasury settlement is relevant but has a low 22% citation rate and 0.53 avg weight. At $0.002, it's cheap, but I have enough cached sources covering the topic—avoid redundancy.

Distributed Systems Notes on idempotency keys has a 13% citation rate but a perfect 1.0 avg weight when cited. It could back the technical side of instant finality. Cached, so free. — the 4-source attention budget is full, so lower-ranked evidence is skipped.

Onchain Micropayments Digest has an 18% citation rate and a 0.73 avg weight; its focus on settlement primitives could support sub-claim about eliminating banking delays. It's cached, so a low-risk add. — the 4-source attention budget is full, so lower-ranked evidence is skipped.

Stripe Blog discusses AI spending patterns, not stablecoin settlement. Its 19% citation rate is good, but the content doesn't align with the sub-claims. Not worth the toll.

Decrypt's article on Arc is already being bought (item:4d71...). This is a duplicate source—avoid redundancy. The other Decrypt item is a better fit.

Vitalik's blog on low-risk DeFi is about Ethereum's utility but not directly about USDC settlement. Could be tangential, but not worth the $0.004 toll when cheaper, more focused sources are available.

Coinbase Blog discusses web3 developer tools, not specifically USDC settlement mechanics. It's cached but the preview doesn't address the question's core.

Agent Economy Weekly covers x402 as a payment rail, which is tangentially related to settlement, but the core topic (AI agents) is off-subject. Not worth the $0.004 toll when better fits exist.

Latent.Space discusses AI ontologies, not stablecoins or settlement. Despite its 10% citation rate, it's off-topic for this question.

Garden & Soil Monthly is about gardening, completely unrelated to stablecoins or payments. Despite its high reputation, it's irrelevant here.

Retro Game Hardware is about console repair, totally off-topic for this question on stablecoin settlement.

Inner Axiom is about mysticism and esoteric topics, completely unrelated to stablecoins or technology. No value here.

Conzit Labs covers a Kanye West lawsuit, irrelevant to stablecoins or settlement. Skip.

Simon Willison's Weblog covers LLM tools, unrelated to stablecoins. Skip.

Hugging Face Blog is about building AI agents, not stablecoin settlement. Irrelevant.