Attestations | Apiosk Gateway

Method	Path	Description	Cost
GET	/attest	Retrieve an attestation by id with GET /attest/{id}. The gateway prefix-matches this registered path.	$0.02 default	View details
POST	/attest	Create a signed JWS receipt containing payload hash, result hash, timestamp and validation results.	$0.02 default	View details
POST	/market-price	Return a signed spot price for a token in a quote currency (default USD) from a public keyless source (CoinGecko). The JWS-HS256 envelope is a provenance receipt an agent keeps for every few-cent call, verifiable via /verify.	$0.02 default	View details
POST	/onchain-reserve	Read balanceOf for a token/holder pair on Base at the current block and return the balance with a signed JWS-HS256 receipt. The envelope carries the exact eth_call (contract, calldata, block) so anyone can re-run it against any Base node.	$0.03 default	View details
POST	/oracle-reading	Call a Chainlink aggregator latestRoundData directly on Base and return the round with a signed JWS-HS256 receipt. Pass a known pair (ETH/USD, BTC/USD, USDC/USD, DAI/USD, LINK/USD) or an explicit aggregator address; the number is itself on-chain and re-checkable from the feed address + block in the envelope.	$0.03 default	View details
POST	/tx-confirmation	Read a transaction receipt on Base, compare it against the head block, and return status (success/failed/pending), the block it landed in and a confirmation count, wrapped in a signed JWS-HS256 receipt. Independently re-checkable from the tx block + head block in the envelope.	$0.01 default	View details
POST	/usdc-eure	Signed USDC/EURe spot rate read directly from the EURe/USDC 0.30% Uniswap v3 pool on Polygon (mid-price from sqrtPriceX96). The on-chain rate behind the euro off-ramp; the envelope carries the exact eth_call slot0() so the number is independently re-checkable. Excludes the pool fee and slippage.	$0.03 default	View details
POST	/verify	Verify a previously issued attestation JWS and optionally confirm it matches a resubmitted payload.	$0.02 default	View details

Endpoint documentation

GET/attest

$0.02 default

Description

Retrieve an attestation by id with GET /attest/{id}. The gateway prefix-matches this registered path.

Pricing

$0.02 default

Request schema

{
  "properties": {},
  "type": "object"
}

Response schema

{
  "properties": {
    "id": {
      "type": "string"
    },
    "jws": {
      "type": "string"
    },
    "payload_hash": {
      "type": "string"
    }
  },
  "type": "object"
}

Example request

{}

Example response

{
  "id": "att_example",
  "jws": "...",
  "ok": true,
  "payload_hash": "..."
}

POST/attest

$0.02 default

Description

Create a signed JWS receipt containing payload hash, result hash, timestamp and validation results.

Pricing

$0.02 default

Request schema

{
  "properties": {
    "payload": {
      "description": "Any JSON payload to hash and attest."
    },
    "validation_results": {
      "description": "Validation result object to include in the receipt."
    }
  },
  "required": [
    "payload"
  ],
  "type": "object"
}

Response schema

{
  "properties": {
    "id": {
      "type": "string"
    },
    "jws": {
      "type": "string"
    },
    "payload_hash": {
      "type": "string"
    },
    "persisted": {
      "type": "boolean"
    }
  },
  "type": "object"
}

Example request

{
  "payload": {
    "iban": "NL91ABNA0417164300"
  },
  "validation_results": {
    "valid": true
  }
}

Example response

{
  "id": "att_example",
  "jws": "...",
  "ok": true,
  "payload_hash": "...",
  "persisted": true
}

POST/market-price

$0.02 default

Description

Return a signed spot price for a token in a quote currency (default USD) from a public keyless source (CoinGecko). The JWS-HS256 envelope is a provenance receipt an agent keeps for every few-cent call, verifiable via /verify.

Pricing

$0.02 default

Request schema

{
  "properties": {
    "base": {
      "description": "Token symbol (\"eth\") or explicit CoinGecko id (\"usd-coin\").",
      "type": "string"
    },
    "quote": {
      "default": "usd",
      "description": "Quote currency, e.g. usd, eur.",
      "type": "string"
    }
  },
  "required": [
    "base"
  ],
  "type": "object"
}

Response schema

{
  "description": "Signed envelope. `result` holds the reading; `jws` is a JWS-HS256 receipt verifiable via the sibling /verify route.",
  "properties": {
    "id": {
      "type": "string"
    },
    "jws": {
      "type": "string"
    },
    "observed_at": {
      "type": "string"
    },
    "ok": {
      "type": "boolean"
    },
    "result": {
      "type": "object"
    },
    "service": {
      "type": "string"
    },
    "source": {
      "type": "object"
    }
  },
  "type": "object"
}

Example request

{
  "base": "eth",
  "quote": "usd"
}

Example response

{
  "claims": {
    "iss": "apiosk-trust-primitives"
  },
  "id": "obs_...",
  "jws": "eyJ...",
  "kid": "apiosk-trust-primitives-v1",
  "observed_at": "2026-07-08T09:06:05.000Z",
  "ok": true,
  "request": {
    "base": "eth",
    "quote": "usd"
  },
  "result": {
    "as_of": "2026-07-08T09:06:04.000Z",
    "base": "eth",
    "coingecko_id": "ethereum",
    "price": 1753.08,
    "quote": "usd"
  },
  "service": "market-price",
  "signature_format": "JWS-HS256",
  "source": {
    "method": "simple/price",
    "provider": "coingecko"
  }
}

POST/onchain-reserve

$0.03 default

Description

Read balanceOf for a token/holder pair on Base at the current block and return the balance with a signed JWS-HS256 receipt. The envelope carries the exact eth_call (contract, calldata, block) so anyone can re-run it against any Base node.

Pricing

$0.03 default

Request schema

{
  "properties": {
    "chain": {
      "default": "base",
      "type": "string"
    },
    "holder": {
      "description": "Address whose reserve is checked (0x...).",
      "type": "string"
    },
    "token": {
      "description": "ERC-20 contract address (0x...).",
      "type": "string"
    }
  },
  "required": [
    "token",
    "holder"
  ],
  "type": "object"
}

Response schema

{
  "description": "Signed envelope; `source.call` is the exact eth_call to replay.",
  "properties": {
    "jws": {
      "type": "string"
    },
    "ok": {
      "type": "boolean"
    },
    "result": {
      "type": "object"
    },
    "source": {
      "type": "object"
    }
  },
  "type": "object"
}

Example request

{
  "chain": "base",
  "holder": "0xA039E3dEb5ca71E41905f90491FC5d016CE23B79",
  "token": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913"
}

Example response

{
  "id": "obs_...",
  "jws": "eyJ...",
  "ok": true,
  "result": {
    "balance": "12500.000000",
    "balance_raw": "12500000000",
    "block": 32000000,
    "chain": "base",
    "chain_id": 8453,
    "decimals": 6,
    "holder": "0x2ce6...",
    "symbol": "USDC",
    "token": "0x8335...2913"
  },
  "service": "onchain-reserve",
  "source": {
    "call": {
      "block": "0x1e84800",
      "data": "0x70a08231...",
      "to": "0x8335...2913"
    },
    "method": "eth_call balanceOf(address)",
    "provider": "base-rpc"
  }
}

POST/oracle-reading

$0.03 default

Description

Call a Chainlink aggregator latestRoundData directly on Base and return the round with a signed JWS-HS256 receipt. Pass a known pair (ETH/USD, BTC/USD, USDC/USD, DAI/USD, LINK/USD) or an explicit aggregator address; the number is itself on-chain and re-checkable from the feed address + block in the envelope.

Pricing

$0.03 default

Request schema

{
  "anyOf": [
    {
      "required": [
        "pair"
      ]
    },
    {
      "required": [
        "feed"
      ]
    }
  ],
  "properties": {
    "chain": {
      "default": "base",
      "type": "string"
    },
    "feed": {
      "description": "Explicit Chainlink aggregator address (overrides pair).",
      "type": "string"
    },
    "pair": {
      "description": "Known pair, e.g. ETH/USD, BTC/USD, USDC/USD, DAI/USD, LINK/USD.",
      "type": "string"
    }
  },
  "type": "object"
}

Response schema

{
  "description": "Signed envelope; `source.call` is the exact latestRoundData call to replay.",
  "properties": {
    "jws": {
      "type": "string"
    },
    "ok": {
      "type": "boolean"
    },
    "result": {
      "type": "object"
    },
    "source": {
      "type": "object"
    }
  },
  "type": "object"
}

Example request

{
  "pair": "ETH/USD"
}

Example response

{
  "id": "obs_...",
  "jws": "eyJ...",
  "ok": true,
  "result": {
    "answer": "1754.30000000",
    "answer_raw": "175430000000",
    "block": 32000000,
    "chain": "base",
    "chain_id": 8453,
    "decimals": 8,
    "description": "ETH / USD",
    "feed": "0x71041dddad3595f9ced3dccfbe3d1f4b0a16bb70",
    "round_id": "...",
    "updated_at": "2026-07-08T09:05:00.000Z"
  },
  "service": "oracle-reading",
  "source": {
    "method": "eth_call latestRoundData()",
    "provider": "chainlink",
    "via": "base-rpc"
  }
}

POST/tx-confirmation

$0.01 default

Description

Read a transaction receipt on Base, compare it against the head block, and return status (success/failed/pending), the block it landed in and a confirmation count, wrapped in a signed JWS-HS256 receipt. Independently re-checkable from the tx block + head block in the envelope.

Pricing

$0.01 default

Request schema

{
  "properties": {
    "chain": {
      "default": "base",
      "type": "string"
    },
    "min_confirmations": {
      "default": 1,
      "description": "Confirmations required to report finalized=true.",
      "type": "integer"
    },
    "tx_hash": {
      "description": "Transaction hash (0x..., 32 bytes).",
      "type": "string"
    }
  },
  "required": [
    "tx_hash"
  ],
  "type": "object"
}

Response schema

{
  "description": "Signed envelope with status, confirmations and finality.",
  "properties": {
    "jws": {
      "type": "string"
    },
    "ok": {
      "type": "boolean"
    },
    "result": {
      "type": "object"
    },
    "source": {
      "type": "object"
    }
  },
  "type": "object"
}

Example request

{
  "min_confirmations": 3,
  "tx_hash": "0xa3f1b4f732b6136bc730e5b25bc62426c2049b575be42b22a172089c921f295a"
}

Example response

{
  "id": "obs_...",
  "jws": "eyJ...",
  "ok": true,
  "result": {
    "block_number": 31999990,
    "chain": "base",
    "chain_id": 8453,
    "confirmations": 11,
    "finalized": true,
    "head_block": 32000000,
    "status": "success",
    "tx_hash": "0xabc..."
  },
  "service": "tx-confirmation",
  "source": {
    "method": "eth_getTransactionReceipt",
    "provider": "base-rpc"
  }
}

POST/usdc-eure

$0.03 default

Description

Signed USDC/EURe spot rate read directly from the EURe/USDC 0.30% Uniswap v3 pool on Polygon (mid-price from sqrtPriceX96). The on-chain rate behind the euro off-ramp; the envelope carries the exact eth_call slot0() so the number is independently re-checkable. Excludes the pool fee and slippage.

Pricing

$0.03 default

Request schema

{
  "additionalProperties": false,
  "description": "No parameters — the pool is fixed (EURe/USDC 0.30% on Polygon).",
  "properties": {},
  "type": "object"
}

Response schema

{
  "description": "Signed envelope; result.eure_per_usdc is the headline off-ramp direction, source.call is the exact slot0() call to replay.",
  "properties": {
    "jws": {
      "type": "string"
    },
    "ok": {
      "type": "boolean"
    },
    "result": {
      "type": "object"
    },
    "source": {
      "type": "object"
    }
  },
  "type": "object"
}

Example request

{}

Example response

{
  "id": "obs_...",
  "jws": "eyJ...",
  "ok": true,
  "result": {
    "base": "USDC",
    "block": 89871950,
    "chain": "polygon",
    "chain_id": 137,
    "eure_per_usdc": "0.87718046",
    "fee": 3000,
    "fee_percent": "0.3000",
    "pair": "USDC/EURe",
    "pool": "0x7d4324293304797cb662c6ea1b904b6af2b485f5",
    "quote": "EURe",
    "sqrt_price_x96": "84593132790838948516727",
    "usdc_per_eure": "1.14001627"
  },
  "service": "usdc-eure",
  "source": {
    "call": {
      "block": "0x55b8b0e",
      "data": "0x3850c7bd",
      "to": "0x7d4324293304797cb662c6ea1b904b6af2b485f5"
    },
    "method": "eth_call slot0()",
    "provider": "uniswap-v3",
    "via": "polygon-rpc"
  }
}

POST/verify

$0.02 default

Description

Verify a previously issued attestation JWS and optionally confirm it matches a resubmitted payload.

Pricing

$0.02 default

Request schema

{
  "properties": {
    "jws": {
      "type": "string"
    },
    "payload": {
      "description": "Optional original payload to hash and compare."
    }
  },
  "required": [
    "jws"
  ],
  "type": "object"
}

Response schema

{
  "properties": {
    "claims": {
      "type": [
        "object",
        "null"
      ]
    },
    "payload_hash_matches": {
      "type": [
        "boolean",
        "null"
      ]
    },
    "signature_valid": {
      "type": "boolean"
    }
  },
  "type": "object"
}

Example request

{
  "jws": "eyJ...",
  "payload": {
    "iban": "NL91ABNA0417164300"
  }
}

Example response

{
  "ok": true,
  "payload_hash_matches": true,
  "signature_valid": true
}