# Maintain Custom Addons Dev Watch

> >

- **Type:** Skill
- **Install:** `agentstack add skill-tanstack-cli-maintain-custom-addons-dev-watch`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [TanStack](https://agentstack.voostack.com/s/tanstack)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [TanStack](https://github.com/TanStack)
- **Source:** https://github.com/TanStack/cli/tree/main/packages/cli/skills/maintain-custom-addons-dev-watch
- **Website:** https://tanstack.com/cli

## Install

```sh
agentstack add skill-tanstack-cli-maintain-custom-addons-dev-watch
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Maintain Custom Add-ons In Dev Watch

Use this skill for local add-on authoring workflows where you continuously compile and sync package output into a target app.

## Setup

```bash
npx @tanstack/cli add-on init
npx @tanstack/cli add-on compile
```

## Core Patterns

### Run add-on dev loop while editing source

```bash
npx @tanstack/cli add-on dev
```

### Sync watched framework directory into a sandbox target app

```bash
# --dev-watch is a flag on `create`, not on `dev`
npx @tanstack/cli create my-sandbox --dev-watch ../path/to/framework-dir
```

### Re-run compile before apply when changing metadata

```bash
npx @tanstack/cli add-on compile
npx @tanstack/cli add my-custom-addon
```

## Common Mistakes

### HIGH Use --dev-watch with --no-install

Wrong:
```bash
npx @tanstack/cli create my-sandbox --dev-watch ../my-addon-package --no-install
```

Correct:
```bash
npx @tanstack/cli create my-sandbox --dev-watch ../my-addon-package
```

Dev-watch rejects `--no-install`, so automated loops fail before any sync work starts.

Source: packages/cli/src/dev-watch.ts:112

### HIGH Start dev-watch without valid framework directory

Wrong:
```bash
npx @tanstack/cli create my-sandbox --dev-watch ../missing-or-invalid-dir
```

Correct:
```bash
npx @tanstack/cli create my-sandbox --dev-watch ../valid-framework-dir
```

Watch setup validates that the path exists, is a directory, and contains at least one of `add-ons/`, `assets/`, or `framework.json`. Invalid targets fail before file syncing begins.

Source: packages/cli/src/command-line.ts:599

### CRITICAL Author add-on from code-router project

Wrong:
```bash
npx @tanstack/cli add-on init
```

Correct:
```bash
# Run add-on init from a file-router project
npx @tanstack/cli add-on init
```

Custom add-on authoring expects file-router mode and exits when run from incompatible project modes.

Source: packages/create/src/custom-add-ons/add-on.ts

### HIGH Run add-on workflows without scaffold metadata

Wrong:
```bash
npx @tanstack/cli add-on dev
```

Correct:
```bash
# Run in a project scaffolded by TanStack CLI (contains .cta.json), then:
npx @tanstack/cli add-on dev
```

Custom add-on flows rely on persisted scaffold options, so missing metadata blocks initialization and update paths.

Source: packages/create/src/custom-add-ons/shared.ts:158

### HIGH Tension: Backwards support vs deterministic automation

This domain's patterns conflict with add-addons-existing-app. Tooling assumes reusable automation, but hidden metadata preconditions from legacy support make add-on loops non-portable across repositories.

See also: add-addons-existing-app/SKILL.md § Common Mistakes

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [TanStack](https://github.com/TanStack)
- **Source:** [TanStack/cli](https://github.com/TanStack/cli)
- **License:** MIT
- **Homepage:** https://tanstack.com/cli

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-tanstack-cli-maintain-custom-addons-dev-watch
- Seller: https://agentstack.voostack.com/s/tanstack
- Browse the marketplace: https://agentstack.voostack.com/browse

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