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.
npx skills add PostHog/posthog-foss --skill test-electron-appgit clone --depth 1 https://github.com/PostHog/posthog-fossWrote 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.
[](https://agentmods.dev/skills/posthog/posthog-foss/test-electron-app)<a href="https://agentmods.dev/skills/posthog/posthog-foss/test-electron-app"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/test-electron-app/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.
<a href="https://agentmods.dev/skills/posthog/posthog-foss/test-electron-app"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/test-electron-app.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Tool Misuse · line 116 Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
- medium MCP Rug Pull · line 4 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00112 | $0.03038 |
| Opus 5.5 | $0.00045 | $0.01215 |
| Sonnet 5.5 | $0.00022 | $0.00608 |
| Haiku 4.5 | $0.00011 | $0.00304 |
Grade A, and why
test-electron-app 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 1mo 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.
until curl -s localhost:9222/json/version >/dev/null; do sleep 1; done How it starts
The opening of the file, as written. The whole thing — 239 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test the real PostHog Electron app
Drive the actual running app over the Chrome DevTools Protocol with
agent-browser. The dev app
already launches with --remote-debugging-port=9222 (see apps/code/package.json),
so an agent can connect, snapshot the UI, interact, and (only when asked) screenshot the live app.
This exercises real state: live tRPC, workspace-server, GitHub/Slack and
whatever profile is signed into ~/.posthog-code. Pick the right surface:
| Goal | Tool |
|---|---|
| Verify or screenshot a change in the real app, live data | this skill (agent-browser + CDP :9222) |
| Regression coverage in CI | Playwright E2E (apps/code/tests/e2e/) |
For a live backend-to-desktop test, read
references/local-django-stack.md before starting services.
Prerequisites
npm i -g agent-browser && agent-browser install # once
The app must be running with remote debugging. pnpm dev (or pnpm dev:code)
already passes --remote-debugging-port=9222. Preflight + connect:
pnpm app:cdp # checks agent-browser + that the app is up on :9222, then connects
If it reports the app is not reachable, the app isn't running. Start it, then
retry pnpm app:cdp.
Launching the app yourself (background / no TTY)
Do not use pnpm dev from a non-interactive shell. It builds deps then hands
off to the phrocs TUI process-multiplexer, which aborts without a controlling
terminal (bubbletea: could not open TTY: /dev/tty: device not configured). An
agent in a background shell has no TTY, so pnpm dev cannot launch it headlessly.
Build the workspace deps (TTY-safe, the same step pnpm dev runs first), then
launch only the Electron app with its stdin held open:
pnpm build:deps # turbo build of @posthog/code deps
tail -f /dev/null | pnpm dev:code # run in the background; leave it running
pnpm dev:code is pnpm --filter code start, i.e. electron-vite dev --watch — just
the app, no phrocs TUI; it watches and rebuilds main/preload and hot-reloads the
renderer (fine for screenshotting/interacting). The CDP port (:9222) is opened by
the app itself in dev (the remote-debugging-port switch in
apps/code/src/main/bootstrap.ts), not by a CLI flag.
What ships with it
1 file 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.
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.
- 1mo ago First seen · 239 lines · 112 tokens per session scan A 693ff90e49c2
test-electron-app is a skill published in the GitHub repository PostHog/posthog-foss (725 stars, last pushed today), licensed MIT. It adds 112 tokens to every session and 3,038 once invoked, about $0.0004 per session on Opus 5.5. 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 2026-09-03.
Other skills, from other repositories
browse
Drive a real browser through Aside: open a page, read it, click through a flow, take screenshots, check console errors. (gstack).
cua-driver
Use Cua Driver for desktop or browser tasks that are awkward or unavailable through Bash/APIs, or when the user explicitly wants GUI interaction: app testing, visual bug reproduction, form filling, calendar entry, screenshots, and demo recording. Also covers Cua setup; not OpenAI Codex Computer Use or web research.
create-verification-skill
Create a repo-local verification skill and exhaustive feature map for driving a real app through its UI, CLI, or API. Use for "create a verification skill", "make a verify skill for this repo", or "document how agents can verify this app".
browser-qa
A browser-based quality check for deployed web pages and user flows. It uses browser automation to test rendering, navigation, forms, interactions, responsive behaviour, and accessibility-related issues.
webapp-testing
Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.
smoke-test
Run smoke tests against a deployed or local app based on your git diff. Each test uses Skyvern browser tools (navigate, act, validate, screenshot) with Chrome DevTools MCP as fallback. Posts screenshot evidence as PR comments.