generated: '2026-07-20'
method: searched
source: https://api.metalend.tech/SKILL.md
spec_source: openapi/metalend-rebalancing-openapi.json
summary: >-
  Cross-cutting request/response semantics for the MetaLend Rebalancing API.
  Web3-native: API-key + Origin gate on every call, SIWE/JWT for mutating
  operations, and wallet signatures (EIP-191 / EIP-712 / EIP-3009) on all
  value-moving actions. No pagination or idempotency-key contract; async
  operations are tracked by opaque tracking IDs and polled.
authentication:
  style: apiKey + jwt + origin
  headers:
    - {name: X-API-Key, required: all endpoints}
    - {name: Origin, required: all endpoints, note: "must match allowed origins for the key; default https://app.metalend.tech"}
    - {name: Authorization, value: "Bearer <jwt>", required: deposits/withdrawals/config}
    - {name: X-MetaLend-JWT, value: "Bearer <jwt>", note: "agentic-wallet-safe alias for Authorization; backend accepts both"}
  ref: authentication/metalend-authentication.yml
signing:
  auth: personal_sign (EIP-191) over SIWE (EIP-4361) challenge message
  config: personal_sign over keccak256(abi.encode(managerAddr, protocolIds[], poolAddresses[], domainIds[], spendingCapRaw))
  deposit_gasless: EIP-712 ReceiveWithAuthorization (EIP-3009)
  deposit_approval: on-chain token.approve then unsigned deposit
  withdrawal: EIP-712 Withdrawal typed-data returned by GET /v1/balances (use verbatim)
idempotency:
  supported: false
  note: >-
    No Idempotency-Key header. Deduplication for value-moving calls is achieved
    through client-supplied cryptographic nonces (EIP-3009 nonce on deposits,
    signed deadlines on withdrawals) and server-issued tracking IDs, not a
    generic idempotency contract.
pagination:
  supported: false
  note: Collections (pools, balances, rewards) return full result sets; no cursor/offset params.
async_tracking:
  pattern: tracking-id + polling
  deposit: POST /v1/deposits -> trackingId ; GET /v1/deposits/{trackingId} -> status
  withdrawal: POST /v1/withdrawals -> trackingId ; GET /v1/withdrawals/{trackingId} -> status
  deposit_states: [PROCESSING, BRIDGING, SUCCESS, FAILED, EMERGENCY_WITHDRAW]
  withdrawal_states: [PROCESSING, SUCCESS, FAILED]
request_tracing:
  field: requestId
  location: error envelope (ApiError.requestId, uuid)
  note: Quote requestId when contacting support@metalend.tech.
versioning:
  scheme: uri-path
  current: v1
  contract_version_endpoint: GET /v1/withdrawals/version
  ref: lifecycle/metalend-lifecycle.yml
error_envelope:
  shape: {code, internalCode, message, requestId, retryAfterSeconds}
  format: custom-json (not RFC 9457)
  ref: errors/metalend-error-codes.yml
rate_limit_signaling:
  status: 429
  retry_hint_field: retryAfterSeconds (in error envelope)
  internal_codes: [RATE_LIMIT_EXCEEDED, THROTTLE_PER_IP]
payments:
  protocol: x402 (HTTP 402 Payment Required)
  observed_on: GET /v1/services
  network: eip155:8453 (Base)
  asset: USDC (0x833589fcd6edb6e08f4c7c32d4f71b54bda02913)
  note: Some resources are gated behind agentic x402 micropayments in USDC on Base.
cross_links:
  authentication: authentication/metalend-authentication.yml
  errors: errors/metalend-error-codes.yml
  lifecycle: lifecycle/metalend-lifecycle.yml
  conformance: conformance/metalend-conformance.yml
  agent_guide: skills/metalend-agent-flow.md