test-t3-app

A workflow for running and testing the T3 Code web app in an isolated development environment. T3 Code is the application this workflow targets, and isolated means the test uses separate files and settings from other work.

In plain words
What is it for?
Starting the web app, pairing a browser with it, testing authentication, managing development servers across sessions, and inspecting or preparing its local SQLite database.
Why use it?
It reduces the risk of tests affecting shared development data and covers sign-in pairing, local servers, and test-state recovery.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/pingdotgg/t3code/test-t3-app
Any agent
npx skills add pingdotgg/t3code --skill test-t3-app
Clone the repo
git clone --depth 1 https://github.com/pingdotgg/t3code

Made for: Claude Code, Codex.

Per session 100 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,616 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
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 $0.00100 $0.01616
Opus 5 $0.00050 $0.00808
Sonnet 5 $0.00020 $0.00323
Haiku 4.5 $0.00010 $0.00162

Measured 2d ago against content hash 6e2062ea00e2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

test-t3-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 2d 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.

When another person will use the printed pairing URL, first open the shared origin without the pairing path or fragment in the controlled browser and confirm the T3 Code app loads. This browser navigation is required eve
.agents/skills/test-t3-app/SKILL.md · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Test T3 App

Use this skill for the web client. For iOS Simulator, Android Emulator, or physical-device testing against an isolated T3 backend, use the sibling test-t3-mobile skill.

Start an isolated web environment

  1. Run commands from the repository root.
  2. Choose a base directory that belongs only to the current worktree or test:
    • Use the repository's ignored .t3 directory for reusable worktree-local state.
    • Use mktemp -d /tmp/t3code-test.XXXXXX for disposable state and retain the printed absolute path.
  3. Start the full web stack with vp run dev. Add --share when the user needs to open it from another tailnet device. In a linked worktree it defaults to that worktree's gitignored .t3; pass --home-dir <base-dir> only when the test needs a different isolated directory.
  4. Keep the terminal session alive and read the selected server port, web port, base directory, and pairing URL from its output.

Treat a base directory as disposable only when it was created or deliberately selected for the current test. Never delete or directly seed the shared ~/.t3 directory. Prefer starting with a new temporary base directory over clearing state of uncertain ownership.

The worktree-local default deliberately outranks an ambient T3CODE_HOME; do not pass the shared home through to a worktree dev server.

Ports are derived from the worktree path but can shift when occupied. Always read the actual values from the [dev-runner] line.

Shared browser dev is single-origin: Vite proxies the backend paths, so never set VITE_HTTP_URL or VITE_WS_URL for dev/dev:web.

The dev runner disables browser auto-open by default. Do not pass --browser during automated testing: an automatically opened page can consume the one-time bootstrap token before the controlled browser uses it.

Verify a shared environment before human handoff

When another person will use the printed pairing URL, first open the shared origin without the pairing path or fragment in the controlled browser and confirm the T3 Code app loads. This browser navigation is required even when curl succeeds because browsers block some otherwise reachable ports before making a network request.

Read the full file on GitHub · 91 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. 2d ago First seen · 91 lines · 100 tokens per session scan A 6e2062ea00e2

Subscribe to this mod's changes

test-t3-app is a skill published in the GitHub repository pingdotgg/t3code (21,041 stars, last pushed 3d ago), licensed MIT. It adds 100 tokens to every session and 1,616 once invoked, about $0.0005 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.

Related

Other skills, from other repositories

browse

Fast headless browser for QA testing and site dogfooding. (gstack).

garrytan/gstack · 19 tokens

use-agent-browser-for-airi

Test AIRI display-model imports with agent-browser across stage-tamagotchi Electron, stage-web, and stage-pocket mobile web layouts. Use when uploading and verifying contributor-supplied Live2D ZIP, VRM, or MMD ZIP/PMX/PMD files through AIRI's model selector, including onboarding bypass, format-specific import…

moeru-ai/airi · 87 tokens

agent-browser

Browser automation CLI for AI agents. Use when the user needs to interact with websites, including navigating pages, filling forms, clicking buttons, taking screenshots, extracting data, testing web apps, or automating any browser task. Triggers include requests to "open a website", "fill out a form", "click a…

moeru-ai/airi · 200 tokens

e2e-deployment-skill

Use this deployment skill to verify shared skills load during Playwright startup.

danny-avila/LibreChat · 22 tokens

launch

Launch Code OSS (VS Code from sources) into an isolated throwaway profile with unique debug ports so you can drive it with @playwright/cli AND attach a Node debugger via dap-cli in the same session. Use when working on VS Code itself and you want to interact with the running workbench, automate chat or UI flows, test…

microsoft/vscode · 96 tokens

playwright-cli

Automates browser interactions for web testing, form filling, screenshots, and data extraction using playwright-cli. Use when the user needs to navigate websites, interact with web pages, fill forms, take screenshots, test web applications, extract information from web pages, mock network requests, manage browser…

zebbern/claude-code-guide · 67 tokens