Euler Finance Chains API

openapi: 3.2.0
info:
  title: Euler Data API (V3) Chains API
  version: 3.0.0
  description: API specification for Euler Data v3.
servers:
- url: /
  description: Current environment
security: []
tags:
- name: Chains
  description: Chain inventory and per-chain protocol summaries. These replace ad-hoc chain-level aggregates from legacy APIs with explicit, cacheable resources.
paths:
  /v3/chains:
    get:
      tags:
      - Chains
      summary: List supported chains
      x-status: implemented
      x-cache-ttl: 300
      responses:
        '200':
          description: Chains
          headers:
            Cache-Control:
              $ref: '#/components/headers/Cache-Control'
            X-Request-Id:
              $ref: '#/components/headers/X-Request-Id'
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Chain'
                  meta:
                    $ref: '#/components/schemas/PaginationMeta'
      operationId: getChains
  /v3/chains/{chainId}/stats:
    get:
      tags:
      - Chains
      summary: Chain-level stats
      description: Returns chain-scoped EVK lending aggregates. `earnTotalAssetsUsd` is reported separately and is not part of `totalSuppliedUsd` or `utilization`.
      x-status: implemented
      x-cache-ttl: 60
      parameters:
      - $ref: '#/components/parameters/ChainIdPath'
      responses:
        '200':
          description: Chain stats
          headers:
            Cache-Control:
              $ref: '#/components/headers/Cache-Control'
            X-Request-Id:
              $ref: '#/components/headers/X-Request-Id'
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    $ref: '#/components/schemas/ChainStats'
                  meta:
                    $ref: '#/components/schemas/PaginationMeta'
      operationId: getChainsByChainIdStats
  /v3/chains/{chainId}/borrowable-vaults:
    get:
      tags:
      - Chains
      summary: Borrowable vaults for a chain
      deprecated: true
      description: Legacy location for this collection.
      x-status: implemented
      x-cache-ttl: 300
      parameters:
      - $ref: '#/components/parameters/ChainIdPath'
      responses:
        '200':
          description: Borrowable vaults
          headers:
            Cache-Control:
              $ref: '#/components/headers/Cache-Control'
            X-Request-Id:
              $ref: '#/components/headers/X-Request-Id'
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      type: string
                  meta:
                    $ref: '#/components/schemas/PaginationMeta'
      operationId: getChainsByChainIdBorrowableVaults
components:
  parameters:
    ChainIdPath:
      name: chainId
      in: path
      required: true
      schema:
        type: integer
  schemas:
    Chain:
      type: object
      required:
      - id
      - name
      properties:
        id:
          type: integer
        name:
          type: string
        status:
          type: string
          nullable: true
          description: Optional chain health status.
    ChainStats:
      allOf:
      - $ref: '#/components/schemas/ProtocolStats'
      - type: object
        required:
        - chainId
        properties:
          chainId:
            type: integer
            description: Chain ID for the returned chain-scoped aggregate.
    ProtocolStats:
      type: object
      description: EVK lending aggregates across the selected chains, with Earn TVL reported separately.
      properties:
        totalSuppliedUsd:
          type: number
          description: Total EVK lending supply in USD. This is the sum of vault `cash + totalBorrows` valued in USD and excludes Earn vault assets.
        totalBorrowedUsd:
          type: number
          description: Total EVK lending borrows in USD across the selected chains.
        earnTotalAssetsUsd:
          type: number
          description: Total Earn vault assets in USD. Reported separately and not included in `totalSuppliedUsd` or `utilization`.
        utilization:
          type: number
          description: EVK lending utilization, computed as `totalBorrowedUsd / totalSuppliedUsd`. Earn assets are excluded from the denominator.
        vaultCount:
          type: integer
        chainCount:
          type: integer
    PaginationMeta:
      type: object
      required:
      - timestamp
      properties:
        total:
          type: integer
          description: Exact total count when the endpoint provides one.
        hasMore:
          type: boolean
          description: Indicates whether another page exists beyond the current page.
        offset:
          type: integer
        limit:
          type: integer
          description: Echoed page size after endpoint-side clamping.
        timestamp:
          type: string
          format: date-time
        chainId:
          type: string
          description: Comma-separated chain IDs for multi-chain responses.
  headers:
    Cache-Control:
      description: Cache policy for this response.
      schema:
        type: string
    X-Request-Id:
      description: Request identifier for tracing.
      schema:
        type: string
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: API key authentication (optional; higher rate limits).
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API key
      description: 'Alternative to X-API-Key using Authorization: Bearer <key>'
    AdminSecret:
      type: apiKey
      in: header
      name: X-Admin-Secret
      description: Admin secret (server-to-server) for API key management.
    PlatformSession:
      type: apiKey
      in: cookie
      name: euler_platform_session
      description: Signed, httpOnly platform-operator browser session cookie.
    PlatformCsrf:
      type: apiKey
      in: header
      name: X-CSRF-Token
      description: Double-submit CSRF token required for unsafe cookie-authenticated methods.