String Apps

A curated collection of production-grade String apps for the String runtime. Each app is a self-contained markdown document (or directory) the agent installs once and uses through /open and /act.

This is the source repo. Apps published from here also appear in the StringHub marketplace under the stringhub namespace.

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What's in this repo

App	What it does	Key dependencies	Auth
translate	Translate text between languages (MyMemory API)	none	none
websearch	Search Wikipedia, Hacker News, DuckDuckGo	none	none
weather	Current weather, forecast, city lookup (Open-Meteo)	none	none
github	Issues, PRs, repos, notifications via gh CLI	gh	gh auth login (one-time, human)
youtube	Video metadata + transcript via yt-dlp	yt-dlp	none
humanizer	Detect AI-writing patterns and suggest fixes	python3	none
docx	Word/PDF read/write, format conversion via pandoc	pandoc (+ optional wkhtmltopdf, pdftotext, libreoffice)	none
whisper	Local speech-to-text with OpenAI Whisper	whisper, ffmpeg	none
notion	Search, read, write, comment on pages; query databases	curl, python3	$NOTION_TOKEN
google	Gmail, Calendar, Drive via gcloud ADC + REST APIs	gcloud	gcloud auth login (one-time, human)
gh-kanban	View a GitHub Projects v2 board as text	gh	gh auth login + OWNER/PROJECT_NUMBER
appkit	Scaffold, validate, and learn to write String apps	none	none

Every app has a requirements.md that spells out exactly what to install and how to authenticate. Agents should read it before running any action.

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Install

The easy way (from the StringHub marketplace):

/install https://stringhub.org/api/install/stringhub/<app-name>

For example:

/install https://stringhub.org/api/install/stringhub/translate
/open app:translate
/act.translate --text "Hello, world" --from en --to ko

The local way (cloning this repo and installing from disk):

git clone https://github.com/string-os/apps.git
cd apps

Then in your String session:

/install ./apps/translate
/open app:translate

Local install is useful when you want to fork an app, edit it, and try the change without going through publish.

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Anatomy of an app

Each app under apps/<name>/ has at minimum:

apps/translate/
├── string.md          ← entry point — opens with /open app:translate
└── requirements.md    ← dependencies, auth, setup steps (read before use)

The setup doc must be named requirements.md (plural): the runtime auto-detects a sibling by that name and surfaces it (Setup: /open requirements.md) on a missing-env warning or an action error. For the hosted/marketplace path, also declare it explicitly with a [!requirements](./requirements.md) directive near the top of string.md.

Multi-page apps add more .md files alongside (and optionally a nav/main.md):

apps/github/
├── string.md
├── requirements.md
├── nav/main.md
├── repos.md
├── issues.md
├── prs.md
└── actions.md

For the SFMD format itself, see the spec. For runtime semantics (how /open, /act, /install work), see the runtime docs.

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Frontmatter conventions used here

---
name: translate              # local registry key (after /install)
namespace: stringhub         # publisher — collision detection identity
version: 1.0.0
type: app                    # or "tool" — decides app: vs tool: lookup
description: ...
tags: [...]
default: <action-id>         # auto-runs on /open, /refresh, /back — only if it takes no required args (optional)
requires: [NOTION_TOKEN]     # required env vars — runtime warns "[!] Missing required env" if unset (optional)
env:                         # human-readable descriptions of those vars; documentation only (optional)
  - name: NOTION_TOKEN
    description: ...
---

(namespace, name) is the canonical identity. Two apps that share name but differ in namespace install side-by-side; the same (namespace, name) re-installs in place.

Note: only requires: triggers the missing-env warning. An env: block alone is descriptive and does not surface a warning — list the var in requires: too if it's mandatory.

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Contributing a new app

1. Make a directory under apps/<name>/ with a string.md and requirements.md.
2. Set namespace to your own publisher handle (not stringhub) and pick a name.
3. Test locally: /install ./apps/<name> then run every action.
4. Open a PR. We'll review for: dependencies clearly stated, every action returns useful output, no destructive operations without explicit user confirmation.

If your app needs human-driven OAuth (browser login), requirements.md MUST tell the AI to ask the human to run the login command — agents can't complete OAuth flows themselves.

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License

MIT. See LICENSE.