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name: minimal-web-baas-demo description: "Fast path for a minimal CloudBase Web + database demo (最小前后端 / 最小可用 fullstack / Lovable-like BaaS). Defaults to @cloudbase/js-sdk client CRUD (NoSQL app.database / PG app.rdb), MCP-only schema, preview-first, and forbids cloud functions unless secrets, cron/background jobs, or logic that security rules/RLS cannot express. Use for 搭一套 demo、留言板、Todo、Notes、Kanban, or when users say 带云函数+云数据库 but only need CRUD. NOT for production multi-service backends, CloudRun, WeChat Mini Programs, or tasks that truly need server secrets." version: 2.34.8 alwaysApply: false

Sibling skills (local only)

Sibling CloudBase skills ship beside this skill. Use local relative paths such as ../web-development/SKILL.md.

If a referenced sibling skill file is missing from this environment, ask the user to install the full CloudBase plugin (or the missing skill). Do not HTTP-fetch remote skill or protocol markdown into the agent context.

Minimal Web BaaS Demo (fast path)

Goal: minutes to an interactive Web + database preview, not a cloud-function middleware stack.

This skill is the product equivalent of CloudBase Sites SessionStart Rule 5 (BaaS-first data persistence).

Activation Contract

Use this first when

• The user asks for a minimal fullstack / 前后端 demo, message board, Todo, Notes, Kanban, or Lovable/Supabase-like quick app on CloudBase Web.
• The user says "带云函数+云数据库" but the real need is CRUD + preview (reinterpret as Web SDK → database).

Do NOT use for

• WeChat Mini Programs (wx.cloud) — use ../miniprogram-development/SKILL.md.
• True server workloads: payments callbacks, SMS providers, secret third-party keys, cron/ETL, WebSockets — use ../cloud-functions/SKILL.md or ../cloudrun-development/SKILL.md.
• Large multi-module products that need ../spec-workflow/SKILL.md.

Hard rules (align with Sites SessionStart Rule 5)

1. BaaS-first data path

   • Schema / admin: Prefer MCP management tools. Do not ask the user to create collections/tables in the console. If MCP tools are missing in this session, configure MCP for next time and use tcb CLI (../cloudbase-cli/SKILL.md) for equivalent schema/admin ops.
     • NoSQL: writeNoSqlDatabaseStructure (create collection / indexes) + permission tools as needed; CLI: NoSQL commands in cloudbase-cli.
     • PostgreSQL: follow ../postgresql-development-cloudbase/SKILL.md (queryPgDatabase / managePgDatabase / migrations); CLI parity via tcb db pg … when MCP is unavailable.
   • Reads / writes: @cloudbase/js-sdk in the browser.
     • NoSQL: app.database() → db.collection(...).get()/add()/update()/watch(...).
     • PG: app.rdb().from(...).
   • Prefer the template helper (often src/utils/cloudbase.ts). Do not invent a second SDK wrapper.

2. Cloud functions are forbidden by default

   • Todo / Notes / Chat / Kanban / "最小前后端 demo" → zero cloud functions.
   • Even if the user says "带云函数", deliver Web SDK → DB and explain in one sentence that cloud functions are not required for CRUD.
   • Create a cloud function only when:
     • (a) the logic cannot be expressed as database security rules / RLS, and
     • (b) it needs server-side secrets / third-party API keys, or it is a scheduled / background job not triggered by a user click.

3. Package discipline

   • Browser: @cloudbase/js-sdk only.
   • Never install @cloudbase/node-sdk (or random stubs) in frontend code.

4. Preview first, deploy second

   • Ship local list + add (or equivalent CRUD) before static hosting / CloudApp deploy.
   • Custom domains, DNS, rollback runbooks → only if the user explicitly asks.
   • Skip Playwright / agent-browser unless the user asks to test.

5. UI ceremony for this path

   • Reuse the template look. Do not load ui-design four-part specs for a minimal demo unless the user asks for visual redesign.
   • "Make me a X app" = X is the homepage (HomePage / App), not a nested demo route beside the welcome page.

6. Anonymous (or real) session before NoSQL CRUD — js-sdk 3.x + publishable key

   • With @cloudbase/js-sdk 3.x initialized via publishable accessKey, call await auth.signInAnonymously() (or an equivalent authenticated session) before any NoSQL app.database() get / add / update / watch.
   • Skipping this yields gateway 401. checkLogin() / getSession() alone does not create a usable write session.
   • Minimal example:

const auth = app.auth
const { error } = await auth.signInAnonymously()
if (error) throw error
const db = app.database()
await db.collection('messages').get()

Capability sniff order (partners + agents)

Use this order for every minimal Web + DB demo. Do not reorder. Cloud functions stay off the critical path.

0. Connector pre-enabled (or shortest Trust path)     ← host / partner packaging
1. Template warmup // parallel with credential wait   ← downloadTemplate + install
2. queryEnv(action="info")                            ← sniff env + RuntimeBackends
3. Lock ONE DB plane (NoSQL | PG | MySQL)             ← no mid-flight thrash
4. MCP schema + minimal permissions                   ← writeNoSql* / PG migrate / MySQL manage
5. Browser @cloudbase/js-sdk CRUD                     ← app.database() / app.rdb()
6. Local preview (list + add)                         ← then ask before deploy
7. Cloud functions                                    ← skip (count = 0) unless secrets/cron/rules-cannot-express

Stack priority for this path: Web SDK CRUD > MCP schema > template warmup > cloud functions.

Standard playbook

1. Warm template in parallel with credentials (see partner notes below): downloadTemplate (react default, vue if requested) → npm install / pnpm install.
2. queryEnv(action="info") → lock one DB plane (NoSQL or PG or MySQL). Do not thrash between them.
3. MCP: create the collection/table + minimal permissions.
4. Frontend: ensure session (auth.signInAnonymously() or equivalent), then wire list + create with @cloudbase/js-sdk (see Hard rule 6).
5. Start / report preview URL; ask before deploy.
6. Cloud function count for this path = 0.

On-demand skills (fetch only when needed)

| Need | Skill | | --- | --- | | Web scaffold / hosting | ../web-development/SKILL.md | | NoSQL browser CRUD | ../cloudbase-document-database-web-sdk/SKILL.md | | PG browser CRUD + MCP schema | ../postgresql-development-cloudbase/SKILL.md | | Auth provider readiness | ../auth-tool-cloudbase/SKILL.md then ../auth-web-cloudbase/SKILL.md |

Prefer searchKnowledgeBase(mode="skill", skillName="minimal-web-baas-demo") (or the sibling dir id) when local skill files are unavailable. Do not dump every CloudBase skill at session start.

WorkBuddy / partner packaging notes (XDF and beyond)

Any partner host (WorkBuddy, CodeBuddy connectors, vertical expert prompts, ISV wrappers) should treat this skill as the compact fast-path brief. Reuse the sniff order above; do not invent a cloud-function-first demo path.

| Host capability | Recommended packaging | | --- | --- | | Full CloudBase Sites plugin | Rely on SessionStart Rule 5 injection + this skill on demand for non-Sites cwd demos. Prefer Sites with CLOUDBASE_SITES_AUTO_INIT=1 for empty-cwd preview. Never guess 5173 — read .cloudbase-sites/preview.json. | | WorkBuddy / connector hosts | Pre-enable the CloudBase MCP connector for the tenant when possible; inject a short system brief that points here; warm downloadTemplate + npm install during credential/Trust wait (do not idle). Optional SessionStart additionalContext can point at this skill — do not ship a separate template-prewarm plugin. | | Expert / vertical prompts (ISVs) | Ship a thin pack: expert Agent markdown (no frontmatter hooks) + optional settings/hooks. Replace any "必须云函数中转 / 前端绝不直连库" language with this BaaS-first contract. |

WorkBuddy SessionStart: https://www.workbuddy.ai/docs/cli/hooks (same additionalContext schema as CodeBuddy/Claude Code). Empty-dir Sites auto-init stays passive unless opted in — do not assume enabling Sites alone warms templates during credential wait.

Do not block first preview on custom domains or org DNS health. DNS issues are a post-preview concern.

One-screen partner paste (optional)

For 最小前后端 / Lovable-like demos: FIRST call
searchKnowledgeBase(mode="skill", skillName="minimal-web-baas-demo"), then Read.
Do not rely only on ad-hoc expert-prompt brief text.
Order: connector ready → template warmup during credential wait → queryEnv →
lock one DB → MCP schema → auth.signInAnonymously() (or session) →
@cloudbase/js-sdk CRUD → preview.
Do not dump all CloudBase skills. Do not create cloud functions for CRUD.
NoSQL without session → gateway 401.