---

name: create-investigation description: Create a new Ethereum data investigation page in the notebooks repo. Use when the user wants to add a new investigation, analysis, or research page that queries Xatu/ClickHouse data and visualizes findings with charts.

Create Investigation

Investigations are one-off analyses of something in Ethereum.

Golden Rules:

• They must use a fixed time range for the data so that the analysis is reproducible.
• Agents must actually check the data - do not make up conclusions. It's better to not write a conclusion than to write a conclusion that is not supported by the data.
• Ask the user for clarifying questions. Be thorough.

Requirements to Gather

1. Title: Investigation title (e.g., "Head Vote Accuracy by Entity Type")
2. Slug: URL-safe identifier (e.g., "head-accuracy-by-entity")
3. Description: Brief description for SEO and sidebar hover
4. Author: Username from supported list (samcm, parithosh, pk910, savid, skylenet, mattevans, qu0b, barnabasbusa, ethpandaops)
5. Tags: Relevant tags for categorization
6. Network: mainnet, sepolia, hoodi, etc.
7. Time Range: Fixed start and end dates (investigations MUST use fixed time ranges for reproducibility)
8. Research Question: The specific question being investigated

File Structure

Create the investigation at pages/YYYY-MM/{slug}/index.md where YYYY-MM is the current year-month.

If the year-month folder doesn't exist, create pages/YYYY-MM/index.md:

---
title: YYYY Mon
sidebar_position: 1
---

Investigations from Month Year.

Page Template

---
title: {Title}
sidebar_position: {N}
description: {Brief description}
date: {YYYY-MM-DDTHH:MM:SSZ}
author: {username}
tags:
  - tag1
  - tag2
---

<script>
    import PageMeta from '$lib/PageMeta.svelte';
    import Section from '$lib/Section.svelte';
    import SqlSource from '$lib/SqlSource.svelte';
</script>

<PageMeta
    date="{YYYY-MM-DD}"
    author="{username}"
    tags={["tag1", "tag2"]}
    description="{Brief description}"
    networks={["Ethereum Mainnet"]}
    startTime="{YYYY-MM-DD}T00:00:00Z"
    endTime="{YYYY-MM-DD}T23:59:59Z"
/>

```sql query_name
SELECT ... FROM xatu_cbt.table_name

Question

{The specific research question being investigated}

Background

{Context and explanation of concepts. Use bold for key terms being defined.}

Investigation

When {Action}

{Explanation of what this analysis shows}

<LineChart data={query_name} x="x_column" y={["Series 1", "Series 2", "Series 3"]} sort=false title="Chart Title" yFmt="num2" chartAreaHeight=400 yMax=100 colorPalette={['#2563eb', '#ea580c', '#16a34a']} echartsOptions={{ title: {left: 'center'}, grid: {bottom: 50, left: 70, top: 60, right: 120}, xAxis: {type: 'category', name: 'X Axis Label', nameLocation: 'center', nameGap: 35}, yAxis: {min: 0, max: 100}, legend: {show: true, right: 10, orient: 'vertical', top: 'center'}, series: [ {name: 'Series 1', lineStyle: {width: 3}}, {name: 'Series 2', lineStyle: {width: 2}}, {name: 'Series 3', lineStyle: {width: 2}} ], graphic: [{ type: 'text', left: 15, top: 'center', rotation: Math.PI / 2, style: { text: 'Y Axis Label', fontSize: 12, fill: '#666' } }] }} />

Takeaways

• Key finding 1
• Key finding 2
• Key finding 3

Critical Rules

1. SQL queries MUST be at top level - Not wrapped in HTML elements or Sections. Evidence's preprocessor won't process them otherwise.

2. Fixed time range required - PageMeta MUST have startTime and endTime props for reproducibility.

3. Escape < and > in prose - Use inline code backticks: `z < 0` not z < 0.

4. Charts require three labels:

   • title prop (centered via title: {left: 'center'})
   • X-axis label via xAxis: {name: '...', nameLocation: 'center', nameGap: 35}
   • Y-axis label via graphic element (NOT yAxis.name which doesn't center properly)

5. Action-based section headers - Use "When Attesting" not "Attester Analysis".

6. No "Analysis" suffix in titles - "Analysis" is implied; use "RPC Snooper Overhead" not "RPC Snooper Overhead Analysis".

7. Don't repeat header - The title from frontmatter is already rendered by the layout.

8. Sort time series data ascending - SQL queries for charts MUST include ORDER BY date_column ASC to ensure data is sorted chronologically. Charts will display incorrectly if data is not sorted.

9. Use high-contrast colors - Multi-line charts MUST use colorPalette with high-contrast colors. Recommended palette:

   • Red: #dc2626
   • Blue: #2563eb
   • Purple: #9333ea
   • Green: #16a34a
   • Orange: #ea580c Example: colorPalette={['#2563eb', '#ea580c', '#16a34a']}

10. Line styling for emphasis - Make the primary metric line thicker (width: 3), use dashed lines for secondary metrics like averages/means:

    series: [
        {name: 'Primary', lineStyle: {width: 3}},
        {name: 'Secondary', lineStyle: {width: 2, type: 'dashed'}}
    ]
    

11. Reference lines with markLine - For horizontal reference lines (e.g., "random chance"), use markLine NOT a separate series (which corrupts the x-axis). Position label inside the chart:

    series: [{
        markLine: {
            silent: true,
            symbol: 'none',
            label: {show: true, position: 'insideEndTop', formatter: 'Label text'},
            lineStyle: {type: 'dashed', color: '#888'},
            data: [{yAxis: 0.56}]
        }
    }]
    

12. Human-readable SQL column names - Use column aliases that will appear nicely in chart legends:

    SELECT
        hour,
        round(avg(our_time)) as "Our Node",
        round(avg(median_time)) as "Network Median"
    

13. Don't describe chart features that don't exist - Never claim "tight IQR band", "green for negative values", or specific colors in prose unless the chart actually shows them. Verify visually before writing conclusions.

14. Per-block comparisons for timing analysis - When comparing timing between nodes, calculate metrics per-block first, then aggregate. Don't compare raw averages across all data which can be misleading.

SQL Source Files

For reusable queries, create sources/xatu_cbt/{query_name}.sql:

SELECT
    date_column,
    column1,
    column2
FROM xatu_cbt.table_name
WHERE slot_start_date_time >= '2025-12-21'
  AND slot_start_date_time < '2026-01-21'
ORDER BY date_column ASC

Then reference in the page:

SELECT * FROM xatu_cbt.{query_name}

Available Chart Types

LineChart, BarChart, AreaChart, ScatterPlot, DataTable, BigValue, Value