go-core

go-core is a skill for Claude Code, Codex from adonai-labs/agent-runway. It costs 76 tokens per session (632 once invoked), scanned A, original, MIT.

A Go-focused implementation guide for backend services and command-line tools. It covers project structure, idiomatic Go patterns, testing, security, and monitoring, and can be invoked for Go-specific questions.

In plain words
What is it for?
Use it when designing or reviewing Go services and CLIs, including their structure, error handling, concurrency, testing, security, and reliability.
Why use it?
It gives practical guidance for making Go code readable, reliable, and suitable for production instead of leaving design decisions inconsistent across a project.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions Claude Code.

Good fit Use it when designing or reviewing Go services and CLIs, including their structure, error handling, concurrency, testing, security, and reliability.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/adonai-labs/agent-runway/skill-go-core
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 adonai-labs/agent-runway --skill skill-go-core
Clone the repo
git clone --depth 1 https://github.com/adonai-labs/agent-runway

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 go-core

README.md
[![agentmods](https://agentmods.dev/badge/skills/adonai-labs/agent-runway/skill-go-core/github.svg)](https://agentmods.dev/skills/adonai-labs/agent-runway/skill-go-core)
Your own site
<a href="https://agentmods.dev/skills/adonai-labs/agent-runway/skill-go-core"><img src="https://agentmods.dev/badge/skills/adonai-labs/agent-runway/skill-go-core/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 go-core

Your own site · 80×15
<a href="https://agentmods.dev/skills/adonai-labs/agent-runway/skill-go-core"><img src="https://agentmods.dev/badge/skills/adonai-labs/agent-runway/skill-go-core.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 76 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 632 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 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 $0.00076 $0.00632
Opus 5 $0.00038 $0.00316
Sonnet 5 $0.00015 $0.00126
Haiku 4.5 $0.00008 $0.00063

Measured 7d ago against content hash 582e38afea24, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

go-core 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 7d 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.

src/stacks/go/skill-go-core/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Go Core

How to invoke

After agent-runway add go, the skill is installed at .cursor/skills/go-core/. Use:

  • Cursor: @go-core or ask a Go question while editing *.go (rules auto-attach)
  • Claude Code: reference .agent-runway/skills/go-core/SKILL.md or ask in context of Go files

Examples:

  • How should I structure this HTTP service?
  • Is this error handling idiomatic Go?
  • How do I test this handler without spinning up a real server?
  • How do I propagate context through this service?

Not sure which skill to use? Start with /start — it classifies intent and routes to the right skill.


Guiding principles

Simplicity is the core Go value. Respect it.

  • Start flat; add packages only when the code genuinely separates
  • Explicit over implicit — no magic, no frameworks that hide behaviour
  • One thing per function; keep function bodies short and readable
  • SOLID applies: small interfaces defined at the consumer; single responsibility per package
  • DRY for business rules; duplication in wiring / glue is acceptable
  • Concurrency only when the problem requires it — do not default to goroutines

What this skill helps with

  • Project structure scaled to size — single package to multi-package services
  • Idiomatic error handling, context propagation, and interface design
  • HTTP services with net/http or chi — routing, middleware, error handling
  • Testing: table-driven tests, httptest, Testcontainers
  • Security: OWASP Go, SQL injection, secrets, subprocess safety
  • Observability: slog, OpenTelemetry, health endpoints

Skill files

File Contents
architecture.md Project structure, packages, dependency rules, config
patterns.md Error handling, context, interfaces, service layer
testing.md Table-driven tests, httptest, Testcontainers, benchmarks
security.md SQL injection, input validation, subprocess safety, secrets
observability.md slog, OpenTelemetry, health endpoints
reference.md go.mod, common commands, module conventions

Read the full file on GitHub · 67 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. 7d ago First seen · 67 lines · 76 tokens per session scan A 582e38afea24

Subscribe to this mod's changes

go-core is a skill published in the GitHub repository adonai-labs/agent-runway (2 stars, last pushed 20d ago), licensed MIT. It adds 76 tokens to every session and 632 once invoked, about $0.0004 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 2026-09-03.