diff --git a/src/earn.ts b/src/earn.ts
new file mode 100644
index 00000000..562825b6
--- /dev/null
+++ b/src/earn.ts
@@ -0,0 +1,233 @@
+/**
+ * Types for the LI.FI Earn Data API (`earn.li.fi`).
+ *
+ * Derived from the live API rather than from `earn-openapi.yaml`, which
+ * disagrees with the service in several places — each noted inline. Verified
+ * against 703 vaults across 17 chains and 27 protocols (9 Aug 2026).
+ */
+
+/**
+ * Protocol a vault belongs to.
+ *
+ * `id` is the filter key for `?protocol=`. Ids are read from
+ * `GET /v1/protocols` and never assumed: most are unversioned (`morpho`, not
+ * `morpho-v1`), but `spark-v2` is not, and the convention has changed twice.
+ * Filtering on an id that no longer exists returns `200` with zero results
+ * rather than an error, so a stale value is indistinguishable from an empty
+ * result set.
+ */
+export interface EarnProtocol {
+  id?: string
+  name: string
+  url: string
+}
+
+/** A token the vault holds. */
+export interface EarnUnderlyingToken {
+  symbol: string
+  address: string
+  decimals: number
+  /** Decimal string, present on every token observed live. */
+  priceUsd?: string
+  /** Documented for multi-asset vaults, but not currently emitted. */
+  weight?: number
+}
+
+/**
+ * An incentive token the vault distributes.
+ *
+ * `symbol` and `decimals` are marked required in the OpenAPI spec but are
+ * absent on some entries, so both are optional here.
+ */
+export interface EarnRewardToken {
+  address: string
+  symbol?: string
+  decimals?: number
+  priceUsd?: string
+}
+
+/**
+ * Deposit or redeem route metadata.
+ *
+ * Originally Composer zap-pack metadata. The zap-pack endpoints were
+ * decommissioned in Jun 2026, but the field still populates on vaults.
+ */
+export interface EarnPack {
+  name: string
+  stepsType: string
+}
+
+/**
+ * APY breakdown. **All values are percentages** — `4.63` means 4.63%.
+ *
+ * The OpenAPI spec, the quickstart and the how-it-works page all describe
+ * these as decimals, and the quickstart multiplies by 100. They are wrong:
+ * doing so overstates every yield by 100x. Values above 1 are common, and
+ * a normaliser keyed on "below 1 means decimal" would misread the 165 vaults
+ * that legitimately yield under 1%.
+ *
+ * `reward` is three-valued and the distinction is load-bearing:
+ * - `null` — the protocol reported nothing. Unknown, not zero.
+ * - `0` — the protocol reported that there are no incentives.
+ * - `> 0` — incentives, as a percentage.
+ *
+ * The split varies *within* a protocol, so it cannot be inferred from
+ * `protocol.id`. Coercing `null` to `0` destroys the only signal that
+ * separates organic yield from an emission that can end.
+ */
+export interface EarnApy {
+  base: number | null
+  total: number
+  reward: number | null
+}
+
+/**
+ * Total value locked.
+ *
+ * `usd` is a **number**. The OpenAPI spec declares it a string, and it was one
+ * before the Apr 2026 rewrite. Typed as a union so a flip in either direction
+ * is not a breaking change for consumers.
+ */
+export interface EarnTvl {
+  usd: number | string
+  native?: number | string
+}
+
+/**
+ * Vault analytics.
+ *
+ * `updatedAt` is documented as refreshing every 15 minutes. In practice the
+ * fleet refreshes in one hourly batch firing at :01–:03, so most vaults share a
+ * single `updatedAt` minute and the freshest reading is over an hour old. The
+ * size of that cluster is a function of how far into the hour you sample, so it
+ * is not worth quoting as a constant. A tail runs past 90 hours. Treat this as
+ * a coarse staleness signal, not a freshness guarantee.
+ */
+export interface EarnAnalytics {
+  apy: EarnApy
+  tvl: EarnTvl
+  apy1d: number | null
+  apy7d: number | null
+  apy30d: number | null
+  updatedAt: string
+}
+
+/** One reason contributing to a vault's verification status. */
+export interface EarnVerificationBreakdown {
+  /** e.g. `zero_apy`, `apy_outlier`. */
+  reason: string
+  /** e.g. `flagged`, `passed`. */
+  result: string
+}
+
+/** Deposit capacity limits. Documented in the spec; not currently emitted. */
+export interface EarnCaps {
+  totalCap?: number | string
+  maxCap?: number | string
+}
+
+/**
+ * A yield vault indexed by LI.FI Earn.
+ *
+ * `caps`, `timeLock` and `kyc` are documented in `earn-openapi.yaml` but are
+ * sent by zero vaults; they are optional here so code written against the spec
+ * still compiles, but they should not be relied on.
+ *
+ * Note also that `isTransactional` describes intent, not capability: the Earn
+ * index is a superset of what Composer can route, so a vault can carry
+ * `isTransactional: true` and still have no routing edge to enter it.
+ */
+export interface EarnVault {
+  address: string
+  chainId: number
+  name: string
+  slug: string
+  network: string
+  /** Present on roughly 23% of vaults. */
+  description?: string
+  protocol: EarnProtocol
+  syncedAt: string
+  /** Observed values include `single`, `multi`, `stablecoin`, `il-risk`. */
+  tags: string[]
+  underlyingTokens: EarnUnderlyingToken[]
+  /** Absent rather than empty when the vault emits no rewards. */
+  rewardTokens?: EarnRewardToken[]
+  analytics: EarnAnalytics
+  isTransactional: boolean
+  isRedeemable: boolean
+  depositPacks: EarnPack[]
+  redeemPacks: EarnPack[]
+  /**
+   * Vault quality signal — undocumented, but present on every vault and set to
+   * `flagged` on roughly 10% of them.
+   */
+  verificationStatus?: string
+  verificationStatusBreakdown?: EarnVerificationBreakdown[]
+  /** Documented but never emitted. */
+  caps?: EarnCaps
+  /** Documented but never emitted. */
+  timeLock?: number
+  /** Documented but never emitted. */
+  kyc?: boolean
+}
+
+/**
+ * A page of vaults.
+ *
+ * `nextCursor` is **absent from the JSON** on the final page — not null, not an
+ * empty string — so it must be both optional and nullable. Callers should treat
+ * missing and null identically when paginating.
+ */
+export interface EarnVaultListResponse {
+  data: EarnVault[]
+  nextCursor?: string | null
+  total: number
+}
+
+/** A chain with at least one indexed vault. Returned as a bare array. */
+export interface EarnChain {
+  chainId: number
+  name: string
+  networkCaip: string
+}
+
+/** A single position in a wallet's Earn portfolio. */
+export interface EarnPosition {
+  chainId: number
+  /** The vault contract. */
+  address?: string
+  protocolName: string | null
+  asset: {
+    address: string
+    name: string
+    symbol: string
+    decimals: number
+  }
+  balanceUsd: string | null
+  balanceNative: string | null
+}
+
+/**
+ * A wallet's Earn positions.
+ *
+ * The array was renamed `positions` → `data` in Aug 2026 with no changelog
+ * entry. Both are declared so consumers can migrate without a breaking change.
+ */
+export interface EarnPortfolioResponse {
+  data?: EarnPosition[]
+  /** @deprecated Renamed to `data` in Aug 2026. */
+  positions?: EarnPosition[]
+  limit?: number
+}
+
+/**
+ * Field-level validation failure.
+ *
+ * Only `400` responses carry these. `404` returns a bare
+ * `{ statusCode, message }` despite the changelog announcing structured 404s.
+ */
+export interface EarnApiFieldError {
+  code: string
+  message: string
+  path: (string | number)[]
+}
diff --git a/src/index.ts b/src/index.ts
index ca3aefba..eea038cf 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,9 +1,10 @@
 export * from './api.js'
+export * from './balance/index.js'
 export * from './bridges.js'
 export * from './chains/index.js'
+export * from './earn.js'
 export * from './errors.js'
 export * from './exchanges.js'
 export * from './step.js'
 export * from './tokens/index.js'
-export * from './balance/index.js'
 export * from './typed-data.js'