Function Turns Bitcoin into Programmable Capital with FBTC Agent SDK

Function, a Bitcoin-centered DeFi infrastructure entity, has unveiled the FBTC Agent software development kit. With this toolkit, which is set to turn Bitcoin into programmable capital, Function is transforming beyond cross-chain liquidity and wrapped assets. As Function disclosed in its official press release, the initiative lets AI agents read positions, prepare transfers, and evaluate market context. As a result, the SDK enables the $BTC liquidity flow into different lending markets, along with maintaining user control over the final execution.

Bitcoin is becoming programmable capital.
Introducing the Function FBTC Agent SDK—agent-native tools for bringing FBTC into DeFi across Ethereum and @Mantle_Official.
Built for developers using Vercel AI SDK, custom agent loops, or Coinbase AgentKit.

— Function 🌗 (@FunctionBTC) July 20, 2026

Function’s FBTC Agent SDK Goes Live to Revolutionize Bitcoin’s Role in DeFi

The FBTC Agent SDK’s launch by Function marks a key development toward redefining Bitcoin ($BTC) into an agent-accessible and active asset to work within the DeFi networks. Additionally, the SDK delivers agent-native instruments for developers to seamlessly integrate with entities like Vercel AI SDK, customized agent loops, and Coinbase AgentKit.

Apart from that, it discloses FBTC metadata, transfer streams for $FBTC supply, and lending market particulars on Aave V3 (Mantle and Ethereum). Builders can now develop workflows where AI agents reportedly query balances, ready lending transfers, and inspect reserves, all while guaranteeing deterministic validation as well as execution. The respective approach addresses the rising demand for exclusive and programmable BTCFi instruments that merge user-controlled security with automation.

Simultaneously, Function has officially released a couple of packages with particular execution boundaries. Particularly, the “@functionfbtc/sdk-agent” package is reportedly framework-agnostic, focusing on conservative transfer preparation. So, it generates transfer parameters for consumer review. As a result, it guarantees that agents never submit or sign transfers directly. On the other hand, the “@functionfbtc/sdk-agentkit” package widens Coinbase AgentKit with the registration of Aave V3 and FBTC actions. The version also executes authorizations and supplies via configured wallets, sending back transfer receipts for more transparency.

Transforming Bitcoin into Programmable Capital

According to Function, the SDK backs Aave V3-based $FBTC lending positions across Mantle and Ethereum. Therefore, Agents can seamlessly observe health factors, query balances, and manage withdrawal, supply, repayment, and borrowing operations, including stablecoins like $USDe, $USDT, and $USDC. Interestingly, the SDK implements network prompts, guaranteeing that Mantle and Ethereum contexts remain recognizable. Overall, the rollout highlights a wider market trend where Bitcoin ($BTC) is more than digital gold, transforming into a programmable capital that can be integrated into the next-gen DeFi stack.