error-handling

error-handling is a skill for Claude Code, Codex from amadeus-dlc/amadeus. It costs 66 tokens per session (321 once invoked), scanned A, original, Apache-2.0.

Guidance for choosing how software reports and handles errors across business logic, application services, and infrastructure. It classifies errors by cause and by whether the caller can recover from them.

In plain words
What is it for?
Use it to design typed domain errors, validation results, exceptions, retry and timeout policies, causal context, and error conversion between layers.
Why use it?
It prevents ordinary business failures from being treated like crashes and keeps retries, logging, and low-level details at the correct boundaries.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/amadeus-dlc/amadeus/error-handling
Any agent
npx skills add amadeus-dlc/amadeus --skill error-handling
Clone the repo
git clone --depth 1 https://github.com/amadeus-dlc/amadeus

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for error-handling

README.md
[![agentmods](https://agentmods.dev/badge/skills/amadeus-dlc/amadeus/error-handling.svg)](https://agentmods.dev/skills/amadeus-dlc/amadeus/error-handling)
Your own site
<a href="https://agentmods.dev/skills/amadeus-dlc/amadeus/error-handling"><img src="https://agentmods.dev/badge/skills/amadeus-dlc/amadeus/error-handling.svg" alt="Measured on agentmods" height="20"></a>
Per session 66 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 321 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00066 $0.00321
Opus 5 $0.00033 $0.00161
Sonnet 5 $0.00013 $0.00064
Haiku 4.5 $0.00007 $0.00032

Measured 5d ago against content hash 7ae5938e0485, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

error-handling scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

amadeus/spaces/default/knowledge/amadeus-shared/software-design/error-handling/SKILL.md · 44 lines

What it actually says

Error Handling

Choose error mechanisms by recoverability and caller responsibility.

Workflow

  1. Classify each error as domain, validation, application, infrastructure, programming defect, or fatal system condition.

  2. Use typed Result/Either-style returns for recoverable domain and validation errors.

  3. Use exceptions or panics for defects and truly exceptional infrastructure failures when callers cannot make a local decision.

  4. Preserve causal context without leaking secrets.

  5. Put retry, timeout, and circuit-breaker policy at integration boundaries.

Rules

  • Domain errors should be explicit in function signatures where the language supports it.

  • Do not use exceptions for ordinary business branching.

  • Log once at the boundary that handles or reports the error.

  • Convert low-level errors into application-facing errors at layer boundaries.

Reference

Read references/guidelines.md for detailed patterns.

Detailed Reference

For non-trivial implementation, review, or refactoring work, read references/details.md before giving final guidance. It contains the detailed rules, examples, smells, and migration notes that do not belong in the short invocation body.

Output

Return the error taxonomy, mechanism choices, API changes, and tests.

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 44 lines · 66 tokens per session scan A 7ae5938e0485

Subscribe to this mod's changes

error-handling is a skill published in the GitHub repository amadeus-dlc/amadeus (8 stars, last pushed 15d ago), licensed Apache-2.0. It adds 66 tokens to every session and 321 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.