Error handling conventions using AppError across all layers.
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.
The line at the top of this page pins the label git:20260915.d786bb4, 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.
The registry has recorded 5 versions of this file, between Jan 3, 2026 and Sep 15, 2026, about one every 64 days. Its first recorded version is graded A and its latest B.
B 13 of 14 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
fail: Size between 200 bytes and 200 KB (199 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
pass: No script tag
Starting a new one? Use the Cursor rule starter on mdpantry, which passes every one of these checks and says what to change in it.
Source
GitHub
pubky/pubky-app · 26 stars · license MIT · pushed 2026-11-02 · branch dev
API
GET https://markdownregistry.com/api/v1/artifacts/art_o6lpdpn5om2fwz4s
GET https://markdownregistry.com/api/v1/resolve?ref=pubky/pubky-app/.cursor/rules/error-handling.mdc
GET https://markdownregistry.com/api/v1/blob/72868288e1ef60a2d550290f5e8edda9379b4e92df9f5ae5beffc2b282e36ffb
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.
pubky/pubky-app · .agents/skills/pubky-code-review/SKILL.md · Run a local code review of a diff against this repo's architecture rules (AGENTS.md, .greptile/config.json) and quality…
pubky/pubky-app · .agents/skills/pubky-staging-invite/SKILL.md · Mints a single-use signup token for the Pubky staging homeserver. Use when the user explicitly asks for a new staging…
pubky/pubky-app · .agents/skills/sentry-nextjs-sdk/SKILL.md · Full Sentry SDK setup for Next.js. Use when asked to "add Sentry to Next.js", "install @sentry/nextjs", or configure…
thedaviddias/front-end-checklist · skills/error-handling/SKILL.md · Use when reviewing scripts, client components, bundles, or runtime behavior related to Implement proper error handling…
ericrisco/rsc-harness · skills/error-handling/SKILL.md · Use when designing the reaction to a class of failures — typed error taxonomies, retry/backoff/timeout policy, circuit…
