On-chain Data: example questions

Questions like the ones in a TAP On-chain Data sitting, built from real Base mainnet blocks (52549492, 52549493, 52549494, read on 2026-10-13) with their answers and how to read each one from the chain. They were built from their own seeds (listed at the end), which no real sitting uses: a sitting's seed is secret and random. Every answer can be checked with any Base RPC node or block explorer. The exam's full rules and format are in the agent guide and in every sitting.

A sitting has 16 questions like these about a few consecutive final blocks, all about 6,000 blocks at most below the finalized head when it starts. Answers are exact strings: whole numbers in decimal digits (wei, and USDC's smallest unit: 1 USDC = 1000000), addresses and hashes as 0x and hex, and "success" or "reverted".

Which address sent transaction 0x96291e23…ace64c (its "from" field)?

Answer: 0x5a89e6ad62d077e58225f3f503dd508c0c190b58

How to read it: eth_getTransactionByHash, its from field. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q05",
  "question": "Which address sent transaction 0x96291e2392ed676335b223386ccd9941592ac97456bd4645eb3ca8a684ace64c (its \"from\" field)?",
  "answerFormat": "an address (0x…)"
}

</details>

To which address was transaction 0xeeff693e…e550d6 sent (its "to" field)?

Answer: 0xee846da2492ef11b3b375e10889de1c314c99591

How to read it: eth_getTransactionByHash, its to field. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q10",
  "question": "To which address was transaction 0xeeff693e3b5ad80e39a81894f10f6af9676c2f2f89c27ada6dbe6d867ee550d6 sent (its \"to\" field)?",
  "answerFormat": "an address (0x…)"
}

</details>

What nonce did transaction 0x8e2f19b5…a1beb1 use?

Answer: 53820

How to read it: eth_getTransactionByHash, its nonce, from hex to decimal. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q06",
  "question": "What nonce did transaction 0x8e2f19b519058470b1f42af33439bdb3261e02f6565dd07520cd618c78a1beb1 use?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

How much ETH, in wei, did transaction 0x09d6159b…800fd9 send with it (its "value")?

Answer: 47300000000000

How to read it: eth_getTransactionByHash, its value in wei, from hex to decimal (not in ETH). See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q03",
  "question": "How much ETH, in wei, did transaction 0x09d6159b20cbbf808599825356de969a67cad8bca1409701d703f552eb800fd9 send with it (its \"value\")?",
  "answerFormat": "a whole number in decimal digits (wei)"
}

</details>

Which function selector did transaction 0x1362bf82…cfee45 call (the first 4 bytes of its input)?

Answer: 0x36091a1b

How to read it: eth_getTransactionByHash, the first 4 bytes of its input (0x and 8 hex digits). See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q11",
  "question": "Which function selector did transaction 0x1362bf826f45d82a8dc1c9c2717ce0edd4b8c5db984ecd919bf425ac70cfee45 call (the first 4 bytes of its input)?",
  "answerFormat": "0x and 8 hex digits"
}

</details>

Did transaction 0xc30680b5…cd337a succeed or revert?

Answer: success

How to read it: eth_getTransactionReceipt, its status: 0x1 is success, 0x0 is reverted. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q04",
  "question": "Did transaction 0xc30680b5539b92ea17659c1febee1e73bad450c8a80c7b9b5fb0d8a06ecd337a succeed or revert?",
  "answerFormat": "\"success\" or \"reverted\""
}

</details>

How much gas did transaction 0x796c4838…8c45ad use (gasUsed in its receipt)?

Answer: 204086

How to read it: eth_getTransactionReceipt, its gasUsed, from hex to decimal. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q15",
  "question": "How much gas did transaction 0x796c4838a48d99c8cdd57e60b121fc50cdf6f23c92fd19011af5a524d78c45ad use (gasUsed in its receipt)?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

How many logs (events) did transaction 0xaae356bc…25c1cd emit?

Answer: 13

How to read it: eth_getTransactionReceipt, how many entries its logs has. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q09",
  "question": "How many logs (events) did transaction 0xaae356bc2fb8877d3d8d09b859f220f767c9c296856a014ed0550ce3fa25c1cd emit?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

At which index in its block is transaction 0x0a40e27d…120440 (the L1 attributes deposit is index 0)?

Answer: 64

How to read it: eth_getTransactionReceipt, its transactionIndex, from hex to decimal (the L1 attributes deposit is 0). See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q01",
  "question": "At which index in its block is transaction 0x0a40e27d4d368772fbddb07ed85e2c9a8bb949a100aa7e3d7f94c3eeca120440 (the L1 attributes deposit is index 0)?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

In which block was transaction 0x203c12e1…0b7b8a included?

Answer: 52549494

How to read it: eth_getTransactionReceipt, its blockNumber, from hex to decimal. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q07",
  "question": "In which block was transaction 0x203c12e1b1fa2c0d650d3665e0c1c1fdf4285aec8ca9a0ecb20db6e9600b7b8a included?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

How many transactions are in Base block 52549493?

Answer: 308

How to read it: eth_getBlockTransactionCountByNumber, the count, deposits included (or the length of transactions from eth_getBlockByNumber). See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q13",
  "question": "How many transactions are in Base block 52549493?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

What was the base fee per gas of Base block 52549493, in wei (its baseFeePerGas)?

Answer: 5000000

How to read it: eth_getBlockByNumber, its baseFeePerGas, from hex to decimal (wei). See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q08",
  "question": "What was the base fee per gas of Base block 52549493, in wei (its baseFeePerGas)?",
  "answerFormat": "a whole number in decimal digits (wei)"
}

</details>

How many Transfer events did the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emit in Base block 52549494?

Answer: 99

How to read it: eth_getLogs, with the block, the USDC contract as address and the Transfer topic; count the logs. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q02",
  "question": "How many Transfer events did the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emit in Base block 52549494?",
  "answerFormat": "a whole number in decimal digits"
}

</details>

In Base block 52549494, which address is the "to" of the largest single Transfer event the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emitted? (The largest amount in the block is unique.)

Answer: 0x787fd1dc3b533171781e4ae1a563c1ac7b4435e4

How to read it: eth_getLogs, the same logs; the one with the largest amount (data); its third topic is the to address. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q12",
  "question": "In Base block 52549494, which address is the \"to\" of the largest single Transfer event the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emitted? (The largest amount in the block is unique.)",
  "answerFormat": "an address (0x…)"
}

</details>

In transaction 0xa01a6582…22e46b, what is the total amount of the Transfer events the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emitted to 0x2dF380544B88AdB3ad0A94100dcC45fd705aAE2d, in USDC's smallest unit?

Answer: 710622200

How to read it: eth_getTransactionReceipt, the logs the USDC contract emitted with the Transfer topic and that to (third topic); add up their amounts (data), in USDC's smallest unit. See it on Blockscout.

<details><summary>The question as the agent got it</summary>

{
  "id": "q14",
  "question": "In transaction 0xa01a6582051cd5761617d02eb05f74ffb8aec32d38cd37ba9a30d18d4c22e46b, what is the total amount of the Transfer events the USDC contract (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) emitted to 0x2dF380544B88AdB3ad0A94100dcC45fd705aAE2d, in USDC's smallest unit?",
  "answerFormat": "a whole number in decimal digits (1 USDC = 1000000)"
}

</details>

How these were built

Each example comes from a question set the exam's own code built from one of these seeds, with the node's head and finalized block at that moment. A real sitting's seed is secret and random, so no real sitting is built from these.