Query Onchain Data

What it does

When your agent uses it

• Your user want to view onchain information about decoded blocks
• Tasks that involve SQL

Example prompts

• “/query-onchain-data”

Requirements

• Node.js
• Pre-approved tools (allowed-tools): Bash(npx awal@2.10.0 status*), Bash(npx awal@2.10.0 balance*), Bash(npx awal@2.10.0 x402 pay *)

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

1. 1Always filter on indexed fields (event_signature, address, block_timestamp) in base.events queries.
2. 2Never use SELECT * - specify only the columns you need.
3. 3Always include a LIMIT clause to bound result size.
4. 4Use event_signature instead of event_name for filtering - it is indexed and much faster.
5. 5Use time-bounded queries with block_timestamp to narrow the scan range.
6. 6Always wrap address values in lower() - the database stores lowercase addresses but users may provide checksummed (mixed-case) addresses…
7. 7Common event signatures: Transfer(address,address,uint256), Approval(address,address,uint256)…

What it can do on your machine

Read from SKILL.md and the folder at commit 238ef60. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Bash(npx awal@2.10.0 status*)
  • Bash(npx awal@2.10.0 balance*)
  • Bash(npx awal@2.10.0 x402 pay *)

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • npx

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • x402.cdp.coinbase.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Query Onchain Data loads about 2.3k tokens when it runs. Until then it costs about 46 tokens; SKILL.md has 799 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~46

When it runs · the whole SKILL.md, loaded when a task matches

~2.3k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from nirholas/three.ws at commit 238ef60, republished under its Apache-2.0 licence (© nirholas). 799 words, ~2,252 tokens.

name

query-onchain-data

description

Query onchain data on Base using the CDP SQL API via x402. Use when you or your user want to view onchain information about decoded blocks, transactions, and events.

allowed-tools

Bash(npx awal@2.10.0 status*), Bash(npx awal@2.10.0 balance*), Bash(npx awal@2.10.0 x402 pay *)

user-invocable

true

disable-model-invocation

false

metadata.category

wallet/payments

metadata.cross-platform-safe

false

metadata.pack

three-ws-skills

npx awal@2.10.0 status

npx awal@2.10.0 x402 pay https://x402.cdp.coinbase.com/platform/v2/data/query/run -X POST -d '{"sql": "<YOUR_QUERY>"}' --json

SELECT
  parameters['from'] AS sender,
  parameters['to'] AS to,
  parameters['value'] AS amount,
  address AS token_address
FROM base.events
WHERE
  event_signature = 'Transfer(address,address,uint256)'
  AND address = '0x833589fcd6edb6e08f4c7c32d4f71b54bda02913'
  AND block_timestamp >= now() - INTERVAL 7 DAY
LIMIT 10

npx awal@2.10.0 x402 pay https://x402.cdp.coinbase.com/platform/v2/data/query/run -X POST -d '{"sql": "SELECT transaction_hash, to_address, value, gas, timestamp FROM base.transactions WHERE from_address = lower('\''0xYOUR_ADDRESS'\'') AND timestamp >= now() - INTERVAL 1 DAY LIMIT 10"}' --json

npx awal@2.10.0 x402 pay https://x402.cdp.coinbase.com/platform/v2/data/query/run -X POST -d '{"sql": "SELECT event_signature, count(*) as cnt FROM base.events WHERE address = lower('\''0xCONTRACT_ADDRESS'\'') AND block_timestamp >= now() - INTERVAL 1 HOUR GROUP BY event_signature ORDER BY cnt DESC LIMIT 20"}' --json

npx awal@2.10.0 x402 pay https://x402.cdp.coinbase.com/platform/v2/data/query/run -X POST -d '{"sql": "SELECT block_number, timestamp, transaction_count, gas_used FROM base.blocks ORDER BY block_number DESC LIMIT 1"}' --json

© nirholas, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .agents/skills/query-onchain-data of nirholas/three.ws.

Open the folder on GitHubat commit 238ef60