posthog-foss: Skill for Claude Code

.agents/skills/documenting-warehouse-sources/SKILL.md

documenting-warehouse-sources is a skill for Claude Code, Codex from PostHog/posthog-foss. It costs 95 tokens per session (1,684 once invoked), scanned A, original, MIT.

A documentation guide for writing PostHog pages that explain how to import data from a warehouse source. PostHog is a product analytics platform, and a data warehouse is a system that stores business data for analysis.

In plain words
What is it for?
Use it when adding, repairing, or standardizing a warehouse-source page in the PostHog documentation repository.
Why use it?
It keeps source documentation consistent and avoids manually duplicating connection fields and supported-table details that the website renders from configuration.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

This is PostHog/posthog-foss's own configuration. It tells Claude Code and Codex how to work on posthog-foss 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 posthog-foss configures →

Needs its repository: it reads a path above its own folder, which exists only inside the repository. The line is import SourceSetupIntro from "../_snippets/source-setup-intro.mdx".

Reuse

Borrowing it

Nothing to install: this file belongs to PostHog/posthog-foss. 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/PostHog/posthog-foss/master/.agents/skills/documenting-warehouse-sources/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/PostHog/posthog-foss

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 documenting-warehouse-sources

README.md
[![agentmods](https://agentmods.dev/badge/skills/posthog/posthog-foss/documenting-warehouse-sources/github.svg)](https://agentmods.dev/skills/posthog/posthog-foss/documenting-warehouse-sources)
Your own site
<a href="https://agentmods.dev/skills/posthog/posthog-foss/documenting-warehouse-sources"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/documenting-warehouse-sources/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 documenting-warehouse-sources

Your own site · 80×15
<a href="https://agentmods.dev/skills/posthog/posthog-foss/documenting-warehouse-sources"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/documenting-warehouse-sources.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 95 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,684 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 $0.00095 $0.01684
Opus 5 $0.00048 $0.00842
Sonnet 5 $0.00019 $0.00337
Haiku 4.5 $0.00010 $0.00168

Measured 9d ago against content hash 4acceabe2823, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

documenting-warehouse-sources 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 9d 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.

.agents/skills/documenting-warehouse-sources/SKILL.md · 159 lines

How it starts

The opening of the file, as written. The whole thing — 159 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Documenting Data warehouse sources

User-facing source docs live in the posthog.com repo (not this one) at contents/docs/cdp/sources/<slug>.md, served at both /docs/cdp/sources/<slug> and /docs/data-warehouse/sources/<slug>. This skill defines the one consistent shape every source doc must follow. Pair it with /implementing-warehouse-sources when shipping a new source.

Assume a sibling posthog.com checkout (e.g. ../posthog.com).

The two things the website renders for you

You do not hand-write connection fields or the table list — both come from the public_source_configs API the site fetches at build time, mirrored into the doc via MDX components:

  • <SourceParameters /> renders the connection/config form fields from get_source_config.fields.
  • <SourceTables /> renders the Supported tables reference (table name, description, sync method, incremental field, primary key) from the source's get_documented_tables().

<SourceTables /> only has data when the source opts in by setting lists_tables_without_credentials = True on its source class (only valid when get_schemas iterates a static endpoint catalog with no I/O — see /implementing-warehouse-sources). Otherwise it renders a generic "discovered from your account" note. If a table is missing or its description is thin, fix the source code (settings.py endpoints + canonical_descriptions.py), not the doc — the doc just renders what the API returns, so the code stays the single source of truth.

Frontmatter

---
title: Linking <Source> as a source
sidebar: Docs
showTitle: true
availability: { free: full, selfServe: full, enterprise: full }
sourceId: <EnumValue> # MUST equal the ExternalDataSourceType value, e.g. ActiveCampaign, Stripe
beta: true # optional — only for beta sources
---

sourceId is what links the doc to its API config (icon, fields, tables). Get it wrong and the doc renders with no <SourceParameters /> / <SourceTables /> data. It must be a real ExternalDataSourceType value (PascalCase, e.g. ActiveCampaign, not Active Campaign).

Read the full file on GitHub · 159 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. 9d ago First seen · 159 lines · 95 tokens per session scan A 4acceabe2823

Subscribe to this mod's changes

documenting-warehouse-sources is a skill published in the GitHub repository PostHog/posthog-foss (714 stars, last pushed today), licensed MIT. It adds 95 tokens to every session and 1,684 once invoked, about $0.0005 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 2026-08-30.

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