effect-qa-mcp: Skill for Claude Code

.agents/skills/effect-ts-errors/SKILL.md

effect-ts-errors is a skill for Claude Code, Codex from forthy/effect-qa-mcp. It costs 22 tokens per session (787 once invoked), scanned A, original, no licence file.

Instructions for handling errors, input checks, and custom error types in Effect-TS, a TypeScript library for composing programs with explicit effects and errors.

In plain words
What is it for?
Use it while implementing validation, error handling, or custom errors in an Effect-TS codebase.
Why use it?
It gives coding guidance for keeping failures and validation rules consistent when using Effect-TS.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing. Also seen: installed under .agents/ (shared by several agents).

This is forthy/effect-qa-mcp's own configuration. It tells Claude Code and Codex how to work on effect-qa-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything effect-qa-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to forthy/effect-qa-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/forthy/effect-qa-mcp/main/.agents/skills/effect-ts-errors/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/forthy/effect-qa-mcp

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 effect-ts-errors

README.md
[![agentmods](https://agentmods.dev/badge/skills/forthy/effect-qa-mcp/effect-ts-errors/github.svg)](https://agentmods.dev/skills/forthy/effect-qa-mcp/effect-ts-errors)
Your own site
<a href="https://agentmods.dev/skills/forthy/effect-qa-mcp/effect-ts-errors"><img src="https://agentmods.dev/badge/skills/forthy/effect-qa-mcp/effect-ts-errors/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for effect-ts-errors

Your own site · 80×15
<a href="https://agentmods.dev/skills/forthy/effect-qa-mcp/effect-ts-errors"><img src="https://agentmods.dev/badge/skills/forthy/effect-qa-mcp/effect-ts-errors.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 787 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00022 $0.00787
Opus 5.5 $0.00009 $0.00315
Sonnet 5.5 $0.00004 $0.00157
Haiku 4.5 $0.00002 $0.00079

Measured 2mo ago against content hash 2450e5c3b3b3, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

effect-ts-errors 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 2mo 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.

.agents/skills/effect-ts-errors/SKILL.md · 102 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 2mo ago First seen · 102 lines · 22 tokens per session scan A 2450e5c3b3b3

Subscribe to this mod's changes

effect-ts-errors is a skill published in the GitHub repository forthy/effect-qa-mcp (0 stars, last pushed 4mo ago), with no licence file. It adds 22 tokens to every session and 787 once invoked, about $0.0001 per session on Opus 5.5. 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.

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