data-lake

data-lake is a skill for Claude Code, Codex from StarRocks/starrocks-debug-skills. It costs 80 tokens per session (5,984 once invoked), scanned A, original, Apache-2.0.

A troubleshooting guide for external data catalogs and storage systems such as Hive, Iceberg, S3, HDFS, and Paimon. It covers the connections, authentication, network, rate-limit, and metadata-cache problems that can affect their queries.

In plain words
What is it for?
Use it to inspect logs, authentication errors, storage access, network usage, and cache behavior when diagnosing external catalog or table problems.
Why use it?
It narrows down why external-table queries fail, hang, or return old data. It organizes investigation around five causes, including Hive Metastore failures, expired Kerberos credentials, storage access issues, network overload, and stale metadata.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to inspect logs, authentication errors, storage access, network usage, and cache behavior when diagnosing external catalog or table problems.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/starrocks/starrocks-debug-skills/data-lake
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add StarRocks/starrocks-debug-skills --skill data-lake
Clone the repo
git clone --depth 1 https://github.com/StarRocks/starrocks-debug-skills

Made for: Claude Code, Codex.

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 data-lake

README.md
[![agentmods](https://agentmods.dev/badge/skills/starrocks/starrocks-debug-skills/data-lake.svg)](https://agentmods.dev/skills/starrocks/starrocks-debug-skills/data-lake)
Your own site
<a href="https://agentmods.dev/skills/starrocks/starrocks-debug-skills/data-lake"><img src="https://agentmods.dev/badge/skills/starrocks/starrocks-debug-skills/data-lake.svg" alt="Measured on agentmods" height="20"></a>
Per session 80 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,984 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00080 $0.05984
Opus 5 $0.00040 $0.02992
Sonnet 5 $0.00016 $0.01197
Haiku 4.5 $0.00008 $0.00598

Measured 8d ago against content hash f186cfed6806, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

data-lake scanned grade A with 1 finding 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 8d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -v --connect-timeout 10 http://<s3-endpoint>/<bucket>/<key>
data-lake/SKILL.md · 629 lines

How it starts

The opening of the file, as written. The whole thing — 629 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Data Lake / External Table Troubleshooting

Investigation guide for Hive Metastore connectivity, Kerberos authentication, HDFS/S3 access errors, and external catalog query failures.

Five root causes account for the vast majority of cases:

  • Cause A — HMS connectivity failure or metadata listing too slow
  • Cause B — Kerberos authentication failure (expired keytab or clock skew)
  • Cause C — S3 / object storage access or rate-limit error
  • Cause D — Network saturation from HMS traffic on CN/BE nodes
  • Cause E — Metadata cache staleness (Hive partitions, Iceberg snapshots)

Metric Taxonomy — Read This First

Before using any diagnostic commands, understand the observable signals for external table issues.

FE log signals (fe.log)

Signal Meaning
Start to connect to Hive metastore + no subsequent Connected HMS TCP connection blocking or timing out
getPartitions / listPartitions with high elapsed ms HMS partition listing slow (large partition count or HMS overload)
Finished replaying journal never appears after HMS connect attempt HMS blocking FE startup sequence
AuthenticationException from catalog connector Kerberos ticket invalid or HMS auth rejected

BE log signals (be.log / be.WARNING)

Signal Meaning
GSS initiate failed Kerberos GSSAPI handshake failed — expired keytab or JCE missing
javax.security.sasl.SaslException SASL negotiation failed — auth or encryption mismatch
503 reduce request rate S3 rate limit hit — partition prefix count too low
Filesystem closed HDFS NameNode cache too small — hdfs_client_max_cache_size must exceed NN count
Network I/O bytes/sec approaching NIC capacity External scan saturating link

Network / thread signals

Signal Meaning
jstack shows threads blocked on TFilterTransport.readAll HMS RPC call blocking; HMS slow or overloaded
sar -n DEV 1 5 shows RX/TX near line rate on CN/BE host Network saturation from remote scan
netstat -s | grep retransmit spike during external scan Packet loss from bandwidth burst

Read the full file on GitHub · 629 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 8d ago First seen · 629 lines · 80 tokens per session scan A f186cfed6806

Subscribe to this mod's changes

data-lake is a skill published in the GitHub repository StarRocks/starrocks-debug-skills (75 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 80 tokens to every session and 5,984 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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