Browser hosts and Project sources

Read this only on a browser host (Claude or ChatGPT on the web, their web Projects) or a runtime that cannot edit files. For a Project on a local host, source-brief.md is enough: it follows the normal local build.

The source is whatever the host put in the model's current context: Project instructions, knowledge files and attachments, past runs the host actually supplied, and the current request. Reading order and the brief headings are in source-brief.md. Do not infer hidden system prompts, account settings, private history, API keys, or credentials. If the host does not show the Project instructions or files to the model, ask for an export or attachment and do not claim the Project was read.

The Dispatch handoff

On a browser host the host is an orchestrator, not the build environment:

1. Write the source brief and the design decisions from step 2 of the skill (archetype, direction, first viewport, sample-data plan, agent moments).
2. Call start-workspace-app-creation on the Agent-Native Dispatch MCP connector (agent-native-dispatch). Put the brief and the design decisions in prompt; pass an appId, a short description, and the template. The tool's schema describes each argument. Send the Project's own text as attachments (attachments.md), never as a summary: the Project instructions as project-instructions.md and every knowledge file, each verbatim as text/plain. Never paste whole knowledge files or binary data into prompt. Attachments are model context and are not copied into the generated workspace, so tell the Builder agent in prompt to persist what the app needs: knowledge files as app resources, the instructions as the in-app agent's instructions. If a file cannot be reproduced verbatim (not in context, too large), say so in the brief and the report; never swap in a digest silently. A workbook cannot be attached (attachments take images, PDF, text, and JSON): pass a bounded CSV rendering as text, or a public URL, and say what was left out.
3. Report what Dispatch actually returned: the branch, the path, and the status. The browser host cannot run or inspect the app, and a returned path can 404 until the branch merges and deploys, so the report ends at pending or unverified unless a status or verification action is available to call.

Rules on this path:

• Never run npm, pnpm, npx, agent-native create, or add-app; never edit files, build in the host's code interpreter, sandbox, or artifact editor, or start a dev server.
• Never substitute the generic create_workspace_app MCP tool. It is a local workspace scaffolder, not the Dispatch handoff.
• If start-workspace-app-creation is unavailable or Dispatch is not authenticated, stop and give the connector setup below. Do not fall back to a sandbox build or claim that the app exists.
• Never invent a Builder branch URL. If Dispatch returns only an acknowledgement, or a path without a URL, report the Dispatch handoff as unverified, not as a ready or verified branch.
• The Dispatch handoff runs without further questions once the brief exists. "When to ask" in SKILL.md still applies before it.

Setting up a browser host

• Install the exported turn-into-app skill where the host supports skills. For a ChatGPT Project or any host that exposes only MCP, put the skill instructions in the Project instructions or knowledge files.
• Add and authenticate the Agent-Native Dispatch MCP connector (https://dispatch.agent-native.com/mcp, OAuth). It reuses or provisions the workspace's Builder project through the Builder Projects API, so no separate Builder CMS or Fusion connector is needed for app creation.

A prompt for a new Project chat:

Turn this project into an app. Use the visible Project instructions,
knowledge files, and any selected successful runs as the source. Create the
app in the connected Agent-Native workspace through Dispatch and Builder, keep
the source brief bounded, and report the real Builder branch or path and the
verification status. Do not build it in this chat's sandbox.