golang-spf13-viper

golang-spf13-viper is a skill for Claude Code from samber/cc-skills-golang. It costs 174 tokens per session (2,560 once invoked), scanned A, original, MIT.

A guide to using Viper, a Go library that reads configuration from several sources, with flags taking priority over environment variables, files, key-value stores, and defaults.

In plain words
What is it for?
Use it when adding layered configuration, binding command-line flags, reading config files, converting settings into Go structs, or reloading settings while a program runs.
Why use it?
It helps keep configuration rules predictable and makes features such as environment-variable mapping, validation into structs, and live file updates easier to implement correctly.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions Claude Code; mentions Codex; built for openclaw.

Part of the cc-skills-golang plugin — 46 skills shipped together

Good fit Use it when adding layered configuration, binding command-line flags, reading config files, converting settings into Go structs, or reloading settings while a program runs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/samber/cc-skills-golang/golang-spf13-viper
About the project

samber/cc-skills-golang is a collection of reusable agent instructions for Go development, covering areas such as the language, testing, security, and observability. It is for coding agents assisting with production-oriented Golang projects. The catalogue entries are its Go-specific skills, rule, plugin, and instruction.

samber/cc-skills-golang · 3,232 stars · on GitHub · skills.sh

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.

Any agent
npx skills add samber/cc-skills-golang --skill golang-spf13-viper
Clone the repo
git clone --depth 1 https://github.com/samber/cc-skills-golang

Made for: Claude Code.

Or install cc-skills-golang, the plugin that ships this one along with the rest of its 46 skills.

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 golang-spf13-viper

README.md
[![agentmods](https://agentmods.dev/badge/skills/samber/cc-skills-golang/golang-spf13-viper/github.svg)](https://agentmods.dev/skills/samber/cc-skills-golang/golang-spf13-viper)
Your own site
<a href="https://agentmods.dev/skills/samber/cc-skills-golang/golang-spf13-viper"><img src="https://agentmods.dev/badge/skills/samber/cc-skills-golang/golang-spf13-viper/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 golang-spf13-viper

Your own site · 80×15
<a href="https://agentmods.dev/skills/samber/cc-skills-golang/golang-spf13-viper"><img src="https://agentmods.dev/badge/skills/samber/cc-skills-golang/golang-spf13-viper.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 174 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,560 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. Third-party audits
  • Socket pass 20 May 2026
  • Snyk pass 20 May 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00174 $0.02560
Opus 5 $0.00087 $0.01280
Sonnet 5 $0.00035 $0.00512
Haiku 4.5 $0.00017 $0.00256

Measured 8d ago against content hash d2f42c2c4445, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

golang-spf13-viper 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 8d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

skills/golang-spf13-viper/SKILL.md · 191 lines

How it starts

The opening of the file, as written. The whole thing — 191 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Persona: You are a Go engineer who treats configuration as a layered system. Flag beats env beats file beats default — and you bind every key so all four layers stay reachable through one API.

Using spf13/viper for layered configuration in Go

Viper resolves configuration values from multiple sources in a fixed precedence order. It has no user-facing surface — it doesn't define commands or flags. Its job is to answer "what is the value of key X right now?" by walking its source layers from highest to lowest priority.

Official Resources:

This skill is not exhaustive — refer to library documentation and code examples for more information:

  • For Go package docs, symbols, versions, importers, and known vulnerabilities, → See samber/cc-skills-golang@golang-pkg-go-dev skill (godig), preferred over Context7 for Go package facts.
  • To navigate this library's usage in your own code (definitions, call sites, diagnostics), → See samber/cc-skills-golang@golang-gopls skill (gopls).
  • Context7 remains a fallback for docs not indexed on pkg.go.dev.
go get github.com/spf13/viper@latest

Viper vs. cobra

Cobra owns the command tree — subcommands, flags, arg validation, completions. Viper owns configuration resolution — it answers "what is the value of key X?" by walking its source layers, with no user-facing surface of its own: it is purely a key-value resolver.

  • Cobra alone — flag-only CLIs.
  • Viper alone — config-file daemons.
  • Both — bind flags at PersistentPreRunE via BindPFlag.

→ See samber/cc-skills-golang@golang-spf13-cobra for the cobra side of this integration.

The precedence pipeline

Viper resolves a key by walking sources in this order (first set value wins):

1. explicit Set()      — viper.Set("key", val)    highest priority
2. flag                — bound pflag.Flag
3. env var             — BindEnv / AutomaticEnv
4. config file         — ReadInConfig / MergeInConfig
5. KV remote           — etcd / Consul
6. default             — viper.SetDefault("key", val)   lowest priority

Read the full file on GitHub · 191 lines

Files

What ships with it

6 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. 8d ago Changed · +8 lines d2f42c2c4445
  2. 10d ago Changed 0eca60e8a939
  3. 13d ago First seen · 183 lines · 174 tokens per session scan A 21ec88fdfdc0

Subscribe to this mod's changes

golang-spf13-viper is a skill published in the GitHub repository samber/cc-skills-golang (3,232 stars, last pushed 5d ago), licensed MIT. It adds 174 tokens to every session and 2,560 once invoked, about $0.0009 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 2026-08-30.

Related

Other skills, from other repositories

stack-trace-go-probe

Internal helper for meta-stack-trace-investigator. Use when a Go panic or stack trace needs Go-specific nil/error checks, go test reproducer guidance, and patch targets.

opensquilla/opensquilla · 42 tokens

site-launch-checklist

Pre-launch checklist for shipping a new website or web app. Scope: analytics (GA4, PostHog, Google Search Console, Ahrefs), DNS, TLS and backups, legal and CNIL/GDPR compliance, security headers, SEO and GEO (robots.txt, sitemaps, llms.txt, hreflang, schema markup, keyword research), copywriting voice via TONE.md and…

samber/cc-skills · 206 tokens

copywriting-hooks

Writes opening hooks and post titles for long-form articles in EN or FR — blog posts, Substack/Medium/dev.to, LinkedIn long-form, newsletters, essays. Trigger whenever the user asks for a hook, opening, lede, intro, first sentence/paragraph, opener, accroche, attaque, phrase d'accroche, or première phrase — including…

samber/cc-skills · 172 tokens

chrome-extension

Build Chrome extensions with Manifest V3. Use this skill whenever the user mentions Chrome extension, browser extension, manifest.json, content script, service worker (in extension context), popup, side panel, chrome.runtime, chrome.tabs, chrome.storage, chrome.scripting, or any Chrome extension API. Also trigger when…

samber/cc-skills · 143 tokens

copywriting-prose-creator

Codifies how a person or brand writes — lexicon, syntax, rhythm, structure, signature moves — into a PROSE.md guide, independent of emotional tone. Builds from SOUL.md and TONE.md, ports a guide to another channel, or reverse-engineers prose patterns from a corpus. Trigger on PROSE.md, writing style guide, prose…

samber/cc-skills · 170 tokens

deep-research

Deep research on any topic — broad parallel web searches, multi-source validation, confidence tracking, and a cited Markdown report. Use whenever the deliverable is a thorough sourced report rather than a quick answer: 'research ', 'deep dive on X', 'analyze the landscape', 'competitive analysis', 'compare these…

samber/cc-skills · 333 tokens