rill: Skill for Claude Code

.claude/skills/investigate/SKILL.md

investigate is a skill for Claude Code from rilldata/rill. It costs 11 tokens per session (302 once invoked), scanned A, original, Apache-2.0.

A bug-investigation workflow that explores several possible causes at the same time using separate agents.

In plain words
What is it for?
It helps gather context from a written problem, Slack messages, or Linear issues, test three to five hypotheses, and report which explanations were supported or rejected.
Why use it?
It reduces the chance of focusing too early on one suspected cause and helps compare competing explanations for a problem.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: names the AskUserQuestion tool.

This is rilldata/rill's own configuration. It tells Claude Code how to work on rill itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything rill configures →

About the project

Rill is a business intelligence tool for turning data sources into SQL models, metrics, dashboards, and natural-language analysis. It is used by business users and coding agents, with OLAP engines such as ClickHouse and DuckDB supporting its queries. Its catalogue add-ons support agent-driven work on Rill projects.

rilldata/rill · 2,970 stars · on GitHub · rilldata.com

Reuse

Borrowing it

Nothing to install: this file belongs to rilldata/rill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/rilldata/rill/main/.claude/skills/investigate/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/rilldata/rill

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for investigate

README.md
[![agentmods](https://agentmods.dev/badge/skills/rilldata/rill/investigate/github.svg)](https://agentmods.dev/skills/rilldata/rill/investigate)
Your own site
<a href="https://agentmods.dev/skills/rilldata/rill/investigate"><img src="https://agentmods.dev/badge/skills/rilldata/rill/investigate/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for investigate

Your own site · 80×15
<a href="https://agentmods.dev/skills/rilldata/rill/investigate"><img src="https://agentmods.dev/badge/skills/rilldata/rill/investigate.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 11 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 302 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00011 $0.00302
Opus 5.5 $0.00004 $0.00121
Sonnet 5.5 $0.00002 $0.00060
Haiku 4.5 $0.00001 $0.00030

Measured 2mo ago against content hash 9f1321dfb4e5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

investigate scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/investigate/SKILL.md · 33 lines

What it actually says

Investigate a bug by gathering context, then spawning parallel Task agents to test multiple hypotheses simultaneously.

Input: $ARGUMENTS

Instructions

1. Gather Context

Parse the input for links and fetch context:

  • Slack link (contains slack.com/archives): Fetch the message and thread replies via Slack MCP tools
  • Linear issue (ID like ENG-1234 or URL): Fetch via mcp__linear__get_issue, including comments and attachments
  • Free text: Use directly as the problem statement

User-provided hunches should be prioritized when forming hypotheses.

2. Investigate in Parallel

Generate 3-5 hypotheses, then use the Task tool to spawn one agent per hypothesis in a single message (parallel, not sequential). For each agent:

  • subagent_type: "Explore", model: "sonnet"
  • A focused prompt with the hypothesis, what to look for, and what would confirm or refute it

3. Synthesize

After all agents complete, report: which hypotheses were confirmed, refuted, or inconclusive, and recommend next steps.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2mo ago First seen · 33 lines · 11 tokens per session scan A 9f1321dfb4e5

Subscribe to this mod's changes

investigate is a skill published in the GitHub repository rilldata/rill (2,970 stars, last pushed yesterday), licensed Apache-2.0. It adds 11 tokens to every session and 302 once invoked, about $0.0000 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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