Agent skill

Errors

How to define and check error classes in Ledger Live. An agent skill from LedgerHQ/ledger-live.

MITAuto-check passed

Install Errors

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/errors .claude/skills/errors && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .claude/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/errors .agents/skills/errors && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .agents/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/errors .cursor/skills/errors && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .cursor/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/LedgerHQ/ledger-live.git --path .agents/skills/errors

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/errors .gemini/skills/errors && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .gemini/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/errors .github/skills/errors && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .github/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add LedgerHQ/ledger-live --skill errors -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install LedgerHQ/ledger-live errors --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/LedgerHQ/ledger-live.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/errors .opencode/skills/errors && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "errors" agent skill from https://github.com/LedgerHQ/ledger-live/tree/develop/.agents/skills/errors into .opencode/skills/errors/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "errors", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: errors
GitHub stars: 622
Token cost: ~801 tokens
SKILL.md length: 228 words
Files: 1
Skills in repo: 50
Repo updated: Oct 8, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

How to define and check error classes in Ledger Live. An agent skill from LedgerHQ/ledger-live.

SKILL.md covers Define errors, Check error type: prefer… and Where errors live
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Errors is an agent skill from LedgerHQ/ledger-live. How to define and check error classes in Ledger Live. Read when adding a new error, creating an errors.ts file, or checking an error's type.

Its SKILL.md is about 800 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

The repository describes itself as: Mono-repository for Ledger Wallet apps and related packages. The licence is MIT.

Example prompts

“/errors”

What it can do on your machine

Read from SKILL.md and the folder at commit 30d7883. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are typescript).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Errors loads about 801 tokens when it runs. Until then it costs about 37 tokens; SKILL.md has 228 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~37
When it runs · the whole SKILL.md, loaded when a task matches: ~801

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from LedgerHQ/ledger-live at commit 30d7883, republished under its MIT licence (© LedgerHQ). 228 words, ~801 tokens.

Download SKILL.mdSave it as .claude/skills/errors/SKILL.md (or your agent's skills folder).

name: errors
description: How to define and check error classes in Ledger Live. Read when adding a new error, creating an errors.ts file, or checking an error's type.
globs: **/errors.ts, **/errors/**/*.ts

Errors

Each package owns its errors in its own src/errors.ts, as plain native classes. There is no shared errors lib: the former @ledgerhq/errors package has been removed.

Define errors

A package groups its errors in src/errors.ts. Extend Error directly and set a stable name. The name string is the contract — keep it stable, it is what survives across process/serialization boundaries.

// message-only
export class FooNotFound extends Error {
  override name = "FooNotFound";
}

// with a default message
export class InvalidChallenge extends Error {
  override name = "InvalidChallenge";
  constructor() {
    super("backend returned an invalid challenge");
  }
}

// with extra fields
export class HttpError extends Error {
  override name = "HttpError";
  readonly status: number | undefined;
  constructor(message: string, status?: number) {
    super(message);
    this.status = status;
  }
}

Group a family under a per-package base class so callers can catch the whole set:

export class WalletAuthError extends Error {
  override name = "WalletAuthError";
}
export class WalletAuthSignatureError extends WalletAuthError {
  override name = "WalletAuthSignatureError";
  constructor(cause: unknown) {
    super("failed to sign challenge", { cause });
  }
}

See libs/ledger-auth/src/errors.ts for a full reference.

`cause`

Use the native second argument: super(message, { cause }). Error cause was standardized in ES2022 and is supported by modern runtimes; its TypeScript typing (ErrorOptions) requires lib: es2022.error (i.e. es2022). Coin modules and some older packages still target es2020 — there, declare and assign manually:

export class BroadcastError extends Error {
  override name = "BroadcastError";
  cause?: unknown;
  constructor(message: string, cause?: unknown) {
    super(message);
    this.cause = cause;
  }
}

Check error type: prefer `error.name`

Prefer error.name === "FooNotFound" over instanceof FooNotFound.

instanceof breaks once an error crosses a boundary — desktop/mobile IPC, worker messaging, or the external @ledgerhq/coin-module-framework — because the object is rebuilt and loses its prototype. The name string always survives.

// ✅ survives serialization
if (error instanceof Error && error.name === "FooNotFound") { … }

// ⚠️ only works in-process, before any serialization
if (error instanceof FooNotFound) { … }

Use instanceof only when you are certain the error has not crossed a boundary (e.g. caught in the same module that threw it) and you need the typed fields.

Where errors live

Logic in one package → that package's src/errors.ts.
Used only by an app → the app's src/errors.ts (apps/ledger-live-desktop, apps/ledger-live-mobile).
Shared by several coin modules → libs/ledger-wallet-framework/src/errors.ts (@ledgerhq/ledger-wallet-framework/errors), the shared home below the coin layer.

Files

Just SKILL.md in .agents/skills/errors of LedgerHQ/ledger-live.

Open the folder on GitHubat commit 30d7883

Compare with similar skills

Errors next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Errors compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Errors this skillLedgerHQ/ledger-live	622	—	~801	Automated safety check: Pass	MIT	today
Recursive Decision Ledgeraffaan-m/ECC	275k	1 repos	~701	Automated safety check: Pass	MIT	3 days ago
Party Ledger Reconciliationsickn33/agentic-awesome-skills	47k	1 repos	~5.2k	Automated safety check: Pass	MIT	today
Defining Clos Classesultralisp/ultralisp	258	—	~1k	Automated safety check: Pass	None	24 days ago
Ledgeralsk1992/CloddsBot	2.9k	—	~134	Automated safety check: Pass	MIT	5 days ago
Tabler Class Reference Tablestabler/tabler	42k	—	~1.4k	Automated safety check: Pass	MIT	today

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Questions about Errors

What does Errors do?

How to define and check error classes in Ledger Live. An agent skill from LedgerHQ/ledger-live. Errors is an agent skill from LedgerHQ/ledger-live. How to define and check error classes in Ledger Live.

How do I install Errors in Claude Code?

Run `npx skills add LedgerHQ/ledger-live --skill errors -a claude-code`. Or copy the skill folder (.agents/skills/errors in LedgerHQ/ledger-live) into .claude/skills/errors in your project. Claude Code loads it when a task matches its description.

How do I install Errors in Codex?

Run `npx skills add LedgerHQ/ledger-live --skill errors -a codex`. Or copy the skill folder (.agents/skills/errors in LedgerHQ/ledger-live) into .agents/skills/errors in your project. Codex loads it when a task matches its description.

Can I use Errors in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add LedgerHQ/ledger-live --skill errors -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/errors, .gemini/skills/errors, .github/skills/errors and .opencode/skills/errors in your project.

What does Errors need to run?

SKILL.md names no scripts, command-line tools or credentials: Errors is instructions for the agent only.

Does Errors access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Errors safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Errors use?

Errors is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Errors use?

About 801 tokens (SKILL.md is roughly 3.2k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Errors?

Skills that share tags, products or a category with Errors: Recursive Decision Ledger (affaan-m/ECC, 275k stars), Party Ledger Reconciliation (sickn33/agentic-awesome-skills, 47k stars), Defining Clos Classes (ultralisp/ultralisp, 258 stars) and Ledger (alsk1992/CloddsBot, 2.9k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Errors?

LedgerHQ (a GitHub organization) maintains it in LedgerHQ/ledger-live, which has 622 GitHub stars. The repository holds 50 skills in this directory. The repository was last updated on October 8, 2026.

Source: LedgerHQ/ledger-live on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Errors

Install Errors

Facts

At a glance

What it does

Example prompts

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Errors

Define errors

`cause`

Check error type: prefer `error.name`

Where errors live

Files

Compare with similar skills

Similar skills

Recursive Decision Ledger

Party Ledger Reconciliation

Defining Clos Classes

Ledger

Tabler Class Reference Tables

Ledger Tasks Yylo

More from LedgerHQ/ledger-live

Impacting PRs

Cloud Sync Module

Codeownership

Coin Families Contract

Data Layer Advanced

Debug Rn Native Crash

Questions about Errors

Install Errors

Facts

At a glance

What it does

Example prompts

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Errors

Define errors

cause

Check error type: prefer error.name

Where errors live

Files

Compare with similar skills

Similar skills

More from LedgerHQ/ledger-live

Questions about Errors

`cause`

Check error type: prefer `error.name`