reidond/kedra/m06-error-handling

Claude Code and agent skill by reidond/kedra

Trust tier 3
  • community
Source check pending

Checking that the SKILL.md file is still in the repository.

CRITICAL: Use for error handling. Triggers: Result, Option, Error, ?, unwrap, expect, panic, anyhow, thiserror, when to panic vs return Result, custom error, error propagation, 错误处理, Result 用法, 什么时候用 panic

Install

npx vskill@latest install reidond/kedra/m06-error-handling

SKILL.md

The same SKILL.md was published earlier as irfanfaraaz/claude-kit/m06-error-handling.

Error Handling

Layer 1: Language Mechanics

Core Question

Is this failure expected or a bug?

Before choosing error handling strategy:

  • Can this fail in normal operation?
  • Who should handle this failure?
  • What context does the caller need?

Error → Design Question

PatternDon't Just SayAsk Instead
unwrap panics"Use ?"Is None/Err actually possible here?
Type mismatch on ?"Use anyhow"Are error types designed correctly?
Lost error context"Add .context()"What does the caller need to know?
Too many error variants"Use Box<dyn Error>"Is error granularity right?

Thinking Prompt

Before handling an error:

  1. What kind of failure is this?
  • Expected → Result<T, E>
  • Absence normal → Option<T>
  • Bug/invariant → panic!
  • Unrecoverable → panic!
  1. Who handles this?
  • Caller → propagate with ?
  • Current function → match/if-let
  • User → friendly error message
  • Programmer → panic with message
  1. What context is needed?
  • Type of error → thiserror variants
  • Call chain → anyhow::Context
  • Debug info → anyhow or tracing

Trace Up ↑

When error strategy is unclear:

"Should I return Result or Option?"
    ↑ Ask: Is absence/failure normal or exceptional?
    ↑ Check: m09-domain (what does domain say?)
    ↑ Check: domain-* (error handling requirements)
SituationTrace ToQuestion
Too many unwrapsm09-domainIs the data model right?
Error context designm13-domain-errorWhat recovery is needed?
Library vs app errorsm11-ecosystemWho are the consumers?

Trace Down ↓

From design to implementation:

"Expected failure, library code"
    ↓ Use: thiserror for typed errors
 
"Expected failure, application code"
    ↓ Use: anyhow for ergonomic errors
 
"Absence is normal (find, get, lookup)"
    ↓ Use: Option<T>
 
"Bug or invariant violation"
    ↓ Use: panic!, assert!, unreachable!
 
"Need to propagate with context"
    ↓ Use: .context("what was happening")

Quick Reference

PatternWhenExample
Result<T, E>Recoverable errorfn read() -> Result<String, io::Error>
Option<T>Absence is normalfn find() -> Option<&Item>
?Propagate errorlet data = file.read()?;
unwrap()Dev/test onlyconfig.get("key").unwrap()
expect()Invariant holdsenv.get("HOME").expect("HOME set")
panic!Unrecoverablepanic!("critical failure")

Library vs Application

ContextError CrateWhy
LibrarythiserrorTyped errors for consumers
ApplicationanyhowErgonomic error handling
MixedBoththiserror at boundaries, anyhow internally

Decision Flowchart

Is failure expected?
├─ Yes → Is absence the only "failure"?
│        ├─ Yes → Option<T>
│        └─ No → Result<T, E>
│                 ├─ Library → thiserror
│                 └─ Application → anyhow
└─ No → Is it a bug?
        ├─ Yes → panic!, assert!
        └─ No → Consider if really unrecoverable
 
Use ? → Need context?
├─ Yes → .context("message")
└─ No → Plain ?

Common Errors

ErrorCauseFix
unwrap() panicUnhandled None/ErrUse ? or match
Type mismatchDifferent error typesUse anyhow or From
Lost context? without contextAdd .context()
cannot use ?Missing Result returnReturn Result<(), E>

Anti-Patterns

Anti-PatternWhy BadBetter
.unwrap() everywherePanics in production.expect("reason") or ?
Ignore errors silentlyBugs hiddenHandle or propagate
panic! for expected errorsBad UX, no recoveryResult
Box<dyn Error> everywhereLost type infothiserror

Related Skills

WhenSee
Domain error strategym13-domain-error
Crate boundariesm11-ecosystem
Type-safe errorsm05-type-driven
Mental modelsm14-mental-model

Security

  • Security scanPassed, 90 of 100Pattern checks on the skill's files.
  • Model reviewPassed

See the full security report

Quality evaluation

  • Task evaluationNot runNo evaluation yet. Run one in Skill Studio.

See evaluation results

Source

Popularity

7-day trend score
0

Not refreshed yet.

Works with

Any agent vskill installs to: 56 targets in all. These 39 have a page on this site.

  • Claude Code
  • Cursor
  • GitHub Copilot
  • Windsurf
  • Codex
  • Gemini CLI
  • Cline
  • Amp
  • Roo Code
  • Goose
  • Continue
  • Kilo Code
  • Junie
  • Trae
  • OpenHands
  • Qwen Code
  • AI Agent
  • Tabnine Chat
  • Sourcegraph Cody
  • Amazon Q
  • Firebase Genkit
  • Sweep
  • Devin
  • Phind
  • Mentat
  • Claude Desktop
  • Aider
  • GPT Pilot
  • Plandex
  • bolt.new
  • v0
  • Replit Agent
  • Anse
  • TypingMind
  • BetterChatGPT
  • LibreChat
  • Warp AI
  • Pieces
  • Fig AI
Embed badge
vskill VERIFIED badge
[![vskill VERIFIED](https://verified-skill.com/api/v1/skills/reidond/kedra/m06-error-handling/badge)](https://verified-skill.com/skills/reidond/kedra/m06-error-handling)

Something wrong with this skill or its page? Tell us.