What Radius Does

Radius is a settlement network for machine-to-machine payments. It is EVM-compatible, settles transactions in under 500 milliseconds, and executes stablecoin transfers for just $0.0001.

Radius uses SBC as the network’s native stablecoin for payments. The network has a native gas token, RUSD, but gas fees are fixed and do not fluctuate based on network volume: stablecoin transfers always execute for $0.0001. Developers and agents do not need to acquire or hold RUSD to participate. If users don't have RUSD, an automatic turnstile converts SBC to RUSD inline to cover transaction fees. The result is that builders interact entirely in stablecoins, with predictable costs and no token management overhead.

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Key specs:

• Sub-500ms settlement
• $0.0001 per stablecoin transfer (fixed)
• 1,000+ TPS at launch, linearly scalable
• EVM-compatible (with some divergences, more info below)
• SBC for payments, RUSD for gas (auto-converted via Turnstile)

Start Building with the Radius Dev Skill

The fastest way to build on Radius is with LLM-assisted development using the Radius Dev Skill. This is a packaged set of instructions, constraints, and context that keeps an LLM grounded in Radius-specific behavior. This ensures your agent generates functional code instead of defaulting to assumptions based on other networks.

The skill works with Claude Code, Codex-compatible tooling, and other skills-compatible agents.

Install the Skill

Claude Code:

/plugin marketplace add https://github.com/radiustechsystems/skills.git
/plugin install radius-dev@skills


npx skills:

npx skills add radiustechsystems/skills


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The skill is also available as a flat file at https://docs.radiustech.xyz/skills.md.

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What the Skill Covers

Once installed, the skill gives the LLM the context it needs to write valid Radius integrations:

• Network configuration: Ingests Chain ID, RPC endpoints, and fee structure.
• Tooling standards: Uses viem for client libraries, Foundry for smart contract development, TypeScript as the default language, and pnpm as the package manager.
• Fee handling: Uses a transaction cost API instead of Ethereum's default fee estimation.
• Divergences from Ethereum: Updates assumptions such as certain block semantics, fee mechanics, and RPC behavior.

How to Prompt Effectively

Break work into scoped, single-task prompts. Here's the pattern:

1. Prime the model with Radius constraints (chain ID, RPC URL, fee token, tooling standards).
2. Ask for one task at a time with a clear output format.
3. Require deterministic outputs such as precise file edits, minimal diffs, copy-paste-ready. commands.
4. Validate every change through running type checks, verifying fee handling, and confirming  no unwanted assumptions were made.

Example prompt:

“Build Rad Reply. Must use Radius Skill and XMTP (https://docs.xmtp.org/llms/llms-full.txt)

Rad Reply is a paid inbox for humans and agents. Anyone who wants your attention attaches a tiny Radius payment to a message.

The recipient sets a floor price by topic, plus rules like “free for friends, $0.25 for recruiters, $1 for cold sales, $5 for urgent.” If the recipient replies, they keep the fee. If they reject or ignore it, the app can auto-refund all or part of the payment.

Privacy preservation is an important requirement.”

For the full prompting guide and additional templates, see the Build with LLMs page in the docs.

Tools from the Ecosystem

Developers don't have to build everything from scratch. Radius’ launch partners have published open-source tooling that covers common integration patterns.

SBC Developer Toolkit

The SBC Developer Toolkit provides ready-made components for stablecoin payment flows on Radius:

• AppKit: starter template preconfigured with wallet infrastructure and SBC's paymaster for gasless transactions
• Paymaster: customizable account abstraction setup for sponsoring gas and abstracting costs from end users
• x402 Facilitator: enables per-call API billing, pay-per-visit content access, and machine-to-machine payments using the x402 HTTP payment protocol
• x402 SDK: gates an API behind micropayments or pay for x402-gated APIs in a few lines of code

Full documentation: docs.stablecoin.xyz

Get Started with SBC

To start experimenting:

1. Go to the Radius Dashboard and create a wallet
2. Claim $1 of free SBC through the faucet. This funds 10,000 stablecoin transfers on Radius.
3. Use the Radius Testnet for development and testing.

Additional Documentation and Resources

• Docs home: docs.radiustech.xyz
• Build with LLMs guide: docs.radiustech.xyz/get-started/build-with-llms
• Network and RPC config: docs.radiustech.xyz/developer-resources/network-configuration
• Fee mechanics: docs.radiustech.xyz/developer-resources/fees
• Ethereum divergences: docs.radiustech.xyz/developer-resources/ethereum-divergence
• x402 integration: docs.radiustech.xyz/developer-resources/x402-integration
• Contract addresses: docs.radiustech.xyz/developer-resources/contract-addresses
• LLM-readable docs: docs.radiustech.xyz/llms.txt (summary) | docs.radiustech.xyz/llms-full.txt (full)
• GitHub: github.com/radiustechsystems
• Discord: discord.radiustech.xyz

What's Next

This post covers the starting line. Upcoming posts will walk through the applications and demos that developers have already built on Radius, from content gating to API metering to autonomous agent payments. Stay tuned.