narrow-bare-rescue SKILL.md skillA
narrow-bare-rescue from oliver-kriska/claude-elixir-phoenix is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add oliver-kriska/claude-elixir-phoenix/narrow-bare-rescue@git:20260723.d82e8e5Pins git:20260723.d82e8e5 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- oliver-kriska/claude-elixir-phoenix
- Path
targets/codex/skills/narrow-bare-rescue/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260723.d82e8e5, committed Jul 23, 2026
- First version recorded
- Jul 21, 2026
- Size
- 5,343 bytes
- Repository stars
- 573
- License
- MIT
Narrow bare rescue in Elixir so real errors like KeyError and typos;.
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
# Narrow Bare Rescue
Turn `rescue _ -> fallback` into `rescue _ in [ExceptionType1, ExceptionType2] -> fallback`
so programmer bugs propagate while known failure modes stay handled.
## Why this matters
Bare rescues (`rescue _ ->`, `rescue e ->` — any form without an `in` clause) swallow
**every** exception, including `UndefinedFunctionError` from typos, `KeyError` from
misspelled map keys, and `CompileError` from bad HEEx templates. The symptom isn't a stack
trace — it's a silent `{:error, :generic}` or a `nil` fallback. Bugs that should surface
in tests or error reporters become quiet degradations.
The Erlang [Secure Coding Guide](https://www.erlang.org/doc/system/secure_coding.html) makes
the same case at the BEAM level — rule **LNG-002** ("Do Not Use `catch`") warns that the
legacy catch-all form conflates normal returns, throws, and errors. Bare `rescue` in Elixir
is the direct analogue.
## Iron Laws
1. **Never leave `rescue _ ->` or `rescue e ->` without an `in` clause.** Every rescue must
list exact exception types. The Credo check enforces this after cleanup lands.
2. **Cover every exception the code path can actually raise.** Narrowing that drops a real
…Read the whole file at its exact version.
How to install
mdr add oliver-kriska/claude-elixir-phoenix/narrow-bare-rescue@sha256:eedf91822102b6aeThe line at the top of this page pins the label git:20260723.d82e8e5, 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_m3srapbfc74hpxfb)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Jul 21, 2026 and Jul 23, 2026, about one every 2 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260723.d82e8e5 latest | 2026-07-23 | d82e8e5 | 5,343 B | A | view · diff |
| git:20260721.1a43137 | 2026-07-21 | 1a43137 | 5,380 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (5343 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
Source
oliver-kriska/claude-elixir-phoenix · 573 stars · license MIT · pushed 2026-11-06 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_m3srapbfc74hpxfb GET https://markdownregistry.com/api/v1/resolve?ref=oliver-kriska/claude-elixir-phoenix/narrow-bare-rescue GET https://markdownregistry.com/api/v1/blob/eedf91822102b6ae1466e4ebc37fedfdf9e9d4a8bf01da8e841917dbe9514f26
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.
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