Borrowing it
Nothing to install: this file belongs to kaptinlin/go-i18n. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/kaptinlin/go-i18n/main/CLAUDE.mdgit clone --depth 1 https://github.com/kaptinlin/go-i18nWrote 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.
[](https://agentmods.dev/instructions/kaptinlin/go-i18n/claude-md)<a href="https://agentmods.dev/instructions/kaptinlin/go-i18n/claude-md"><img src="https://agentmods.dev/badge/instructions/kaptinlin/go-i18n/claude-md.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.02222 | $0.02222 |
| Opus 5 | $0.01111 | $0.01111 |
| Sonnet 5 | $0.00444 | $0.00444 |
| Haiku 4.5 | $0.00222 | $0.00222 |
Grade A, and why
go-i18n CLAUDE.md 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.
How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
go-i18n
Go internationalization library with ICU MessageFormat support, deterministic fallback chains, and optional net/http locale detection.
For user-facing installation and examples, see README.md.
For internal contracts and design rules, start with SPECS/00-overview.md.
Commands
Use task targets first:
# Tests
task test
task test-verbose
task test-coverage
task bench
# Quality
task fmt
task vet
task lint
task vuln
task verify
Direct Go commands are fine for focused work:
go test -race -p 1 ./...
go test ./... -run TestName
go test -bench=. -benchmem ./...
Architecture
Key files and directories:
i18n.go— bundle construction, locale matching, fallback state, MessageFormat compilation, introspection APIslocalizer.go— locale-scoped lookup and formatting APIsloader.go—LoadMessages,LoadFiles,LoadGlob,LoadFSlocale.go—Accept-Languagematching viagolang.org/x/text/languagedetector.go— request locale detection from query, cookie, header, andAccept-Languagecontext.go— context helpers for*Localizermiddleware/http.go— optional stdlib HTTP middlewareresult.go—TranslationResultandTranslationSourceexamples/— runnable usage examples.references/— pinned upstream implementations used as design evidence, not package contracts
Agent Operating Rules
- Read the relevant SPECS and adjacent tests before changing behavior.
- Reproduce bugs through the caller-visible path before editing implementation.
- Use one behavior-focused vertical slice at a time: RED, GREEN, then refactor.
- Prefer the standard library, current dependencies, and existing package helpers before adding code.
- Apply KISS, DRY, and YAGNI without weakening validation, errors, or tests.
- Keep edits scoped to the requested contract and preserve unrelated worktree changes.
- Resolve conflicting evidence explicitly; fail loudly when a required contract is unclear.
- Match verification to the changed behavior and run the repository gates before shipping.
- Do not add policy-only scripts that merely restate README, AGENTS, or SPECS prose.
- Do not add tests that mirror spec wording when behavior tests already prove the contract.
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.
- 8d ago First seen · 192 lines · 2,222 tokens per session scan A 614dae11d1fc
go-i18n CLAUDE.md is an instructions file published in the GitHub repository kaptinlin/go-i18n (11 stars, last pushed 1mo ago), licensed MIT. It adds 2,222 tokens to every session, about $0.0111 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.
Other instructions, from other repositories
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.