Localized reading guide
chatgpt-appsPurpose, usage and source
Build, scaffold, refactor, and troubleshoot ChatGPT Apps SDK applications that combine an MCP server and widget UI. Use when Codex needs to design tools, register UI resources, wire the MCP Apps bridge or ChatGPT compatibility APIs, apply Apps SDK metadata or CSP or domain settings, or produce a docs-aligned project scaffold. Prefer a docs-first workflow by invoking the openai-docs skill or OpenAI developer docs MCP tools before generating code.
Source retrieved:
- Source repository
- openai/skills
- SKILL.md
skills/.curated/chatgpt-apps/SKILL.md- Repository stars
- 28,420
- Repository updated
- 2026-10-29
- Categories
- Design
- Last collected
License: License file needs review
Workflow excerpts are reading aids, not executable instructions from Codez. No third-party Skill was run to produce this page.
The purpose and workflow passages below are upstream material, organized and translated for reading. They are distinct from the separately labeled Codez editorial analysis.
What this Skill does
Build, scaffold, refactor, and troubleshoot ChatGPT Apps SDK applications that combine an MCP server and widget UI. Use when Codex needs to design tools, register UI resources, wire the MCP Apps bridge or ChatGPT compatibility APIs, apply Apps SDK metadata or CSP or domain settings, or produce a docs-aligned project scaffold. Prefer a docs-first workflow by invoking the openai-docs skill or OpenAI developer docs MCP tools before generating code.
How the upstream workflow works
Mandatory Docs-First Workflow
Use $openai-docs first whenever building or changing a ChatGPT Apps SDK app. Invoke $openai-docs (preferred) or call the OpenAI docs MCP server directly. Fetch current Apps SDK docs before writing code, especially (baseline pages): Fetch apps-sdk/quickstart when scaffolding a new app or generating a first-pass implementation, and check the official examples repo/page before inventing a scaffold from scratch.
Overview
Scaffold ChatGPT Apps SDK implementations with a docs-first, example-first workflow, then generate code that follows current Apps SDK and MCP Apps bridge patterns. Use this skill to produce: A primary app-archetype classification and repo-shape decision A tool plan (names, schemas, annotations, outputs)
Upstream passage · L8 ↗Prompt Guidance
Use prompts that explicitly pair this skill with $openai-docs so the resulting scaffold is grounded in current docs. Preferred prompt patterns:
Requirements and setup
2b. Use the Starter Script When a Low-Dependency Fallback Helps
Use scripts/scaffold_node_ext_apps.mjs only when the user wants a quick, greenfield Node starter and a vanilla HTML widget is acceptable, and no upstream example is a better starting point. Run it only after fetching current docs, then reconcile the generated files with the docs you fetched.
Limits and quality checks
API Surface Guardrails
Some examples wrap the bridge with an app object (for example, @modelcontextprotocol/ext-apps/react) and expose helper names like app.sendMessage(), app.callServerTool(), app.openLink(), or host getter methods. Treat those wrappers as implementation details or convenience layers, not the canonical public API to teach by default.
5. Add Resource Metadata and Security
Set resource metadata deliberately on the widget resource/template: _meta.ui.csp with exact connectDomains and resourceDomains
Start with a safe trial
- Check the supported host and the repository installation instructions. Keep the Skill directory and its referenced scripts, assets and documentation together; SKILL.md alone may omit dependencies.
- Give the agent your real input, desired output and acceptance criteria. Invocation syntax and available tools depend on the host; this site does not assume a universal install command.
- Try the source workflow in a disposable project or on a copy. Review operations that change files, remote services or billable resources before allowing them.
- Validate the output against the source quality checks and your own requirements. A successful trigger or a high repository Star count does not establish a correct result.
Read further in the source
- Overview
- Mandatory Docs-First Workflow
- Prompt Guidance
- Classify The App Before Choosing Code
- Default Starting-Point Order
- 0. Classify The App Archetype
- 1. Plan Tools Before Code
- 2. Choose an App Architecture
- 2a. Start From An Upstream Example When One Fits
- 2b. Use the Starter Script When a Low-Dependency Fallback Helps
- 3. Scaffold the MCP Server
- 4. Scaffold the Widget UI
- API Surface Guardrails
- 5. Add Resource Metadata and Security
- 5a. Enforce A Minimum Working Repo Contract
- 6. Validate the Local Loop
- 7. Connect and Test in ChatGPT (Developer Mode)
- 8. Plan Production Hosting and Deployment
- 9. Prepare Submission and Publish (Public Apps Only)
- Interactive State Guidance
- Output Expectations
- References
Related Skills
Translation and scope
This reading guide selects passages from the pinned upstream SKILL.md. Translation is assisted. It is not a complete manual or a claim of tested compatibility. Read the original and its referenced files before use.
This introduction refers to the pinned version below; current repository activity and collection time are shown separately.
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- Source retrieved
- Source commit
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c3a13a659ce26e9d067b5a97c321e8abec6d8e878afce31b7e841dfcf2635c3a