May Changelog: Borrow API, Refreshed App Pages, and x402 Agent Payments

In May, we added borrow features into our API, added share price charts in the app, and made vaults.fyi easier for agents to use through x402. We also added new portfolio history endpoints, coverage for Liquity, and PAYGO access for our API.

Borrow APIs for wallets, exchanges, and apps

We expanded borrow endpoints so integrators can build borrow flows across supported lending protocols through one integration.

The new /alpha/borrow surface (currently in the alpha version of our API) gives developers a consistent model for market data, user positions, event history, transaction context, and transaction payload generation. Wallets, exchanges, and apps can use it to build crypto-backed borrow experiences across Aave and Morpho markets.

Supported transaction actions include supply, withdraw, borrow, and repay where available for the underlying market.

Refreshed vault pages and upgraded dashboard

The app received a broad visual refresh in May.

The biggest vault page update is share price charts. Users can now inspect vault-level share price history directly from the vault page, making it easier to understand performance over time before depositing.

We also made several upgrades to the Discover page, Dashboard, and our mobile version of the app. Check out the app and let us know what you think.

x402 agent payments and Circle Agent Marketplace

vaults.fyi is now available in Circle's Agent Marketplace, making it easier for agents to discover and pay for vaults.fyi API calls.

Payment-aware clients can now read structured payment-resource metadata directly from our API schema, including fields such as url, description, mimeType, serviceName, tags, iconUrl, and amount. This helps SDKs, API explorers, and agents render payment requirements without custom parsing logic.

In other AI/agent news, we shipped Yield tools for Zerion CLI and a major upgrade to our MCP. Read more about our MCP in Onchain yield tools for any AI agent.

Advanced analytics for vault due diligence

We added POST /alpha/advanced-analytics, a new endpoint for heavier per-vault analytics (currently in the alpha version of our API).

The endpoint mirrors detailed-vault filtering and pagination, while letting integrators opt into specific analytics sections only when they need them. Standard vault queries stay lightweight, and analysts, apps, and agents can pull deeper due diligence metrics when the use case calls for them.

Initial selectors include:

• Max drawdown: the largest observed peak-to-trough decline over the tracked period.
• Withdrawal pause ratio: the share of time withdrawals were paused over the tracked window.
• Full detailed-vault payload: the complete vault response alongside advanced analytics.

Check out the endpoint documentation here.

Coverage

We added coverage for Liquity protocol and 50+ additional new vaults.

vaults.fyi now tracks 1,500+ vaults across 20 networks, giving developers and app teams a broader set of yield opportunities to query, compare, and route into through one API.

API access and Pay-As-You-Go (PAYGO)

API access is also simpler. Invite codes are no longer required, new users can sign up and generate API keys directly.

Sign up here: portal.vaults.fyi/signup.

For developers

In addition to the borrow and advanced analytics endpoints covered above, we added endpoints that make it easier to get historical returns on user portfolio positions.

Portfolio history and vault flows

We added new endpoints for time-windowed portfolio analysis.

The /beta/portfolio/partial-returns/ endpoint calculates a user's vault returns for a specific period. The response gives integrators a way to measure period-specific returns for a specific address.

GET /beta/portfolio/partial-returns/{userAddress}/{network}/{vaultId}

We also added historical user positions with /alpha/historical-positions/. This endpoint returns vaults a user held during a selected window, including positions that existed at the start of the window or were opened during it.

GET /alpha/historical-positions/{userAddress}

For vault-level flow analysis, we added daily deposit and redemption totals:

GET /alpha/historical/{network}/{vaultId}/daily-flows

Together, these endpoints make it easier to reconstruct previous exposure, analyze user performance over a defined period, and monitor vault-level capital movement.

For the full week-by-week list, see the vaults.fyi changelog.

Questions? Reach us at t.me/vaultsfyisupport or x.com/vaultsfyi.