mcp-app-verification SKILL.md skillB
mcp-app-verification from a5c-ai/babysitter is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add a5c-ai/babysitter/mcp-app-verification@git:20260601.da7723aPins git:20260601.da7723a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- B, 16 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- a5c-ai/babysitter
- Path
library/specializations/ai-agents-conversational/skills/mcp-app-verification/SKILL.md- Versions recorded
- 5
- Latest version
- git:20260601.da7723a, committed Jun 1, 2026
- First version recorded
- Apr 4, 2026
- Size
- 11,954 bytes
- Repository stars
- 1,896
- License
- MIT
Comprehensive verification checklists for MCP Apps. Tests with basic-host reference, validates handler-before-connect, text fallback, resource URI linking, single-file bundling, host styling, CSP, and legacy pattern detection.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# mcp-app-verification Run comprehensive verification checklists for MCP Apps covering correctness, compatibility, and migration completeness. ## Overview MCP Apps have several critical invariants that must be verified before deployment. This skill provides systematic verification across multiple dimensions: 1. **Runtime verification**: App loads and functions in basic-host reference 2. **Pattern verification**: Critical code patterns are correct (handler-before-connect, text fallback) 3. **Build verification**: Single-file bundle is valid and complete 4. **Styling verification**: Host theming applies correctly 5. **CSP verification**: All origins declared, no silent failures 6. **Migration verification**: No remaining legacy patterns (OpenAI, old MIME types, snake_case) ## Capabilities ### basic-host Test Execution - Build the MCP App - Start the server - Launch basic-host reference implementation against the server - Verify app loads without console errors - Verify handlers fire correctly ### Handler-Before-Connect Invariant - Search source code for `app.connect()` call …
Read the whole file at its exact version.
How to install
mdr add a5c-ai/babysitter/mcp-app-verification@sha256:6567b98e407928dbThe line at the top of this page pins the label git:20260601.da7723a, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_udw7usuuwfmu7frv)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 5 versions of this file, between Apr 4, 2026 and Jun 1, 2026, about one every 14 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260601.da7723a latest | 2026-06-01 | da7723a | 11,954 B | B | view · diff |
| git:20260507.44b06c0 | 2026-05-07 | 44b06c0 | 12,301 B | B | view · diff |
| git:20260507.50823d8 | 2026-05-07 | 50823d8 | 12,266 B | B | view · diff |
| git:20260507.313363d | 2026-05-07 | 313363d | 12,014 B | B | view · diff |
| git:20260404.bc2ce97 | 2026-04-04 | bc2ce97 | 11,623 B | B | view |
Audit of the latest version
- fail: No script tag (matched: <script)
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (11954 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.
Source
a5c-ai/babysitter · 1,896 stars · license MIT · pushed 2026-11-01 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_udw7usuuwfmu7frv GET https://markdownregistry.com/api/v1/resolve?ref=a5c-ai/babysitter/mcp-app-verification GET https://markdownregistry.com/api/v1/blob/6567b98e407928dbe81a64e1e5daf06367e115ab9499c1b069d149451a0044f3
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.