api-errors

api-errors is a skill for Claude Code from cyanheads/eia-energy-mcp-server. It costs 54 tokens per session (6,958 once invoked), scanned A, original, no licence file.

A reference and set of patterns for handling API errors in @cyanheads/mcp-ts-core. It covers the MCP error constructor, JSON-RPC error codes, and where service errors should be thrown or caught.

In plain words
What is it for?
Use it when looking up error codes, deciding where to throw or catch errors, or using ErrorHandler.tryCatch in services.
Why use it?
It helps developers choose consistent error codes and avoid handling errors in the wrong part of a service.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the eia-energy-mcp-server plugin — 32 skills, 1 MCP server shipped together

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/cyanheads/eia-energy-mcp-server/api-errors
Any agent
npx skills add cyanheads/eia-energy-mcp-server --skill api-errors
Clone the repo
git clone --depth 1 https://github.com/cyanheads/eia-energy-mcp-server

Made for: Claude Code.

Or install eia-energy-mcp-server, the plugin that ships this one along with the rest of its 32 skills, 1 MCP server.

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 api-errors

README.md
[![agentmods](https://agentmods.dev/badge/skills/cyanheads/eia-energy-mcp-server/api-errors.svg)](https://agentmods.dev/skills/cyanheads/eia-energy-mcp-server/api-errors)
Your own site
<a href="https://agentmods.dev/skills/cyanheads/eia-energy-mcp-server/api-errors"><img src="https://agentmods.dev/badge/skills/cyanheads/eia-energy-mcp-server/api-errors.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 6,958 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin unknown 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 $0.00054 $0.06958
Opus 5 $0.00027 $0.03479
Sonnet 5 $0.00011 $0.01392
Haiku 4.5 $0.00005 $0.00696

Measured 6d ago against content hash 140957b2714f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

api-errors scanned grade A with 1 finding 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 6d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

const articles = await ncbi.fetch(input.pmids);
skills/api-errors/SKILL.md · 529 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 6d ago First seen · 529 lines · 54 tokens per session scan A 140957b2714f

Subscribe to this mod's changes

api-errors is a skill published in the GitHub repository cyanheads/eia-energy-mcp-server (2 stars, last pushed 12d ago), with no licence file. It adds 54 tokens to every session and 6,958 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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