tower-ontology

tower-ontology is a skill for Claude Code, Codex from tower/agent-skills. It costs 125 tokens per session (3,511 once invoked), scanned A, original, MIT.

A skill for building a verified map of tables and relationships in an Apache Iceberg lakehouse, a data system that stores large analytical tables. It profiles tables with SQL and records the resulting entity model as catalogue knowledge.

In plain words
What is it for?
Use it to inspect tables, test unique keys and joins, measure nulls and value ranges, document entities, and identify questions that require a human answer.
Why use it?
It reduces the risk of guessing what tables mean or how they join. The model is checked against the data before it is recorded.

Skill for Claude CodeCodex

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

Good fit Use it to inspect tables, test unique keys and joins, measure nulls and value ranges, document entities, and identify questions that require a human answer.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/tower/agent-skills/tower-ontology
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 tower/agent-skills --skill tower-ontology
Clone the repo
git clone --depth 1 https://github.com/tower/agent-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 tower-ontology

README.md
[![agentmods](https://agentmods.dev/badge/skills/tower/agent-skills/tower-ontology/github.svg)](https://agentmods.dev/skills/tower/agent-skills/tower-ontology)
Your own site
<a href="https://agentmods.dev/skills/tower/agent-skills/tower-ontology"><img src="https://agentmods.dev/badge/skills/tower/agent-skills/tower-ontology/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 tower-ontology

Your own site · 80×15
<a href="https://agentmods.dev/skills/tower/agent-skills/tower-ontology"><img src="https://agentmods.dev/badge/skills/tower/agent-skills/tower-ontology.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 125 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,511 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.
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 $0.00125 $0.03511
Opus 5 $0.00063 $0.01755
Sonnet 5 $0.00025 $0.00702
Haiku 4.5 $0.00013 $0.00351

Measured 8d ago against content hash 47a38254a4b3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

tower-ontology 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 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.

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.

skills/tower-ontology/SKILL.md · 245 lines

How it starts

The opening of the file, as written. The whole thing — 245 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Tower Ontology Builder

This skill turns an undocumented catalog into a verified entity model stored on the catalog itself, so every future agent and person starts with the semantics instead of re-deriving them.

Core loop: inventory the catalog → profile each table with SQL → prove the relationships → write each entity to knowledge as you go → report the map and the open questions.

The output is not a document. It is a set of tower catalogs knowledge entries that tower-data reads on its next run.

The one rule that makes this skill worth running

An agent can guess an entity model from column names in seconds, and it will be confidently wrong. This skill's value is that it proves things with SQL before recording them.

Split every claim into two piles:

Derivable from the data — verify, then record Only a human knows — ask, or mark inferred
Grain: is id actually unique? What the entity means to the business
Join validity, cardinality, orphan rate Which of two overlapping tables is authoritative
Enum domains (SELECT DISTINCT status) What "active", "internal", "churned" mean
Null rates, date coverage, row counts Which rows to exclude by default
Whether deleted_at behaves like a soft delete Why a column exists

Never record a guess as confirmed. A wrong confirmed entry is worse than no entry — it silently poisons every future analysis.

Fast path

# 0. Don't clobber existing work
tower catalogs knowledge list default -j

# 1. Whole inventory — every namespace, table, column, and type in one call
tower catalogs show default --full -j

# 2. Per table: one profile query (see the battery below)
tower catalogs query default -j --sql '...'

# 3. Record immediately, one entry per table
tower catalogs knowledge set default entity-bronze-runs --scope table --object bronze.runs ...

Step 0: Check what already exists

tower catalogs knowledge list default -j
  • Empty ([]) — greenfield, run the full pass.
  • Has entries — you are refreshing, not rebuilding. Read existing entries first (knowledge show default <name> -j), diff the inventory against them, and only profile tables that have no entity-* entry or whose columns changed. Never overwrite a confirmed entry sourced from a human with an inferred one of your own; if you believe it's wrong, tell the user and let them decide.

Read the full file on GitHub · 245 lines

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 · 245 lines · 125 tokens per session scan A 47a38254a4b3

Subscribe to this mod's changes

tower-ontology is a skill published in the GitHub repository tower/agent-skills (2 stars, last pushed 1mo ago), licensed MIT. It adds 125 tokens to every session and 3,511 once invoked, about $0.0006 per session on Opus 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 2026-08-31.

Related

Other skills, from other repositories

create-pr

Creates a GitHub PR with a Linear-ticket-prefixed title and a decision-led, narrative description for prisma-next. Use when the user wants to create a pull request, open a PR, or submit changes for review.

prisma/orm · 47 tokens

schema-exploration

Lists tables, describes columns and data types, identifies foreign key relationships, and maps entity relationships in a database. Use when the user asks about database schema, table structure, column types, what tables exist, ERD, foreign keys, or how entities relate.

langchain-ai/deepagents · 57 tokens

ha-data-stores

Map of Hope Agent's local data stores and safe read-only query workflow. Use when the user asks where Hope Agent stores data, wants to inspect sessions/messages/memory/logs/background jobs/knowledge indexes/settings, asks the model to query local app data, or debugging requires checking persisted state. Trigger…

shiwenwen/hope-agent · 115 tokens

supabase

Supabase / PostgREST Row-Level-Security playbook — pull the anon (or leaked servicerole) key out of the frontend JS, map tables from the auto-generated OpenAPI spec, test anonymous RLS READ disclosures (PII/secret leaks), and anonymous RLS WRITE abuse (insert/update/delete — e.g. forging…

PentesterFlow/agent · 120 tokens

nornicdb-cypher-queries

Pick fast, predictable Cypher query shapes in NornicDB — point lookups, batch retrieval, pagination, search, traversal, batched UNWIND/MERGE writes, cleanup, multi-tenant isolation. Use when writing or reviewing Cypher whose latency or throughput matters; maps user intent to the executor's hot-path query templates.

orneryd/NornicDB · 79 tokens

dsql

Build with Aurora DSQL — manage schemas, execute queries, handle migrations, diagnose query plans, diagnose cluster performance, load data, and develop applications with a serverless, distributed SQL database. Covers IAM auth, multi-tenant patterns, MySQL-to-DSQL and PostgreSQL-to-DSQL schema conversion, foreign key…

awslabs/agent-plugins · 229 tokens