ring:using-assert

ring:using-assert is a skill for Cursor from LerianStudio/ring. It costs 99 tokens per session (1,974 once invoked), scanned A, original, Apache-2.0.

A guide for using Lerian’s Go runtime assertion package to check that important conditions hold and to record assertion metrics. It also helps find panic and log.Fatal calls that violate a service’s no-panic policy.

In plain words
What is it for?
Use it to scan a Go codebase for assertion opportunities, check zero-panic compliance, look up assertion functions, and learn how to initialize assertion metrics.
Why use it?
It replaces scattered, hand-written checks with the project’s standard assertion approach and helps reveal places where failures may stop a service abruptly.

Skill for Cursor

Written for Cursor: shipped in a Cursor plugin. Also seen: mentions Claude Code.

Part of the ring-dev-team plugin — 35 skills, 24 agents shipped together

Good fit Use it to scan a Go codebase for assertion opportunities, check zero-panic compliance, look up assertion functions, and learn how to initialize assertion metrics.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/lerianstudio/ring/using-assert
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 LerianStudio/ring --skill using-assert
Clone the repo
git clone --depth 1 https://github.com/LerianStudio/ring

Made for: Cursor.

Or install ring-dev-team, the plugin that ships this one along with the rest of its 35 skills, 24 agents.

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 ring:using-assert

README.md
[![agentmods](https://agentmods.dev/badge/skills/lerianstudio/ring/using-assert/github.svg)](https://agentmods.dev/skills/lerianstudio/ring/using-assert)
Your own site
<a href="https://agentmods.dev/skills/lerianstudio/ring/using-assert"><img src="https://agentmods.dev/badge/skills/lerianstudio/ring/using-assert/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 ring:using-assert

Your own site · 80×15
<a href="https://agentmods.dev/skills/lerianstudio/ring/using-assert"><img src="https://agentmods.dev/badge/skills/lerianstudio/ring/using-assert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 99 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,974 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
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Data Exfiltration · line 60
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
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 $0.00099 $0.01974
Opus 5.5 $0.00040 $0.00790
Sonnet 5.5 $0.00020 $0.00395
Haiku 4.5 $0.00010 $0.00197

Measured 1mo ago against content hash 97cb6be42faa, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

ring:using-assert 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 1mo 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.

dev-team/skills/using-assert/SKILL.md · 166 lines

How it starts

The opening of the file, as written. The whole thing — 166 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ring:using-assert

Moved from lib-commons

The canonical home for this package is now github.com/LerianStudio/lib-observability/assert. It lived in github.com/LerianStudio/lib-commons/v4/commons/assert and github.com/LerianStudio/lib-commons/v5/commons/assert through the v4 and v5 shim period; lib-commons v5 still re-exports every symbol via type aliases and thin wrappers for backward compatibility, but every type and function in lib-commons/v5/commons/assert is marked Deprecated: and delegates to lib-observability/assert. New code MUST import github.com/LerianStudio/lib-observability/assert. Existing imports continue to compile during the deprecation window — there are no behavior changes, only an import-path move.

When to use

Sweep mode:

  • "Sweep the codebase for lib-observability/assert opportunities"
  • "Audit this service for zero-panic policy compliance"
  • "Find panic()/log.Fatal violations"
  • "Replace DIY invariant checks with lib-observability/assert"

Reference mode:

  • "What's the signature for assert.DebitsEqualCredits?"
  • "How do I initialize assertion metrics?"
  • "Should I panic, assert, or return an error here?"
  • "How do I unwrap AssertionError in a Fiber error handler?"

Skip when

  • Working on non-Go services
  • Working on frontend code
  • Target codebase is Ring itself

Similar: ring:using-lib-observability, ring:using-runtime Compatibility: ring:using-lib-commons (covers the v5 deprecation shim and re-export aliases)

Mode Selection

Request Shape Mode
"Sweep / audit for assert opportunities" Sweep
"Find panic()/log.Fatal() violations" Sweep
"What's the signature for X?" Reference
"Should I panic, assert, or return error?" Reference

SWEEP MODE

4-phase sweep. Each phase has a hard gate — do not proceed until the current phase produces its artifact.

Phase 1: Version Reconnaissance   → assert-version-report.json
Phase 2: CHANGELOG Delta Analysis → assert-delta-report.json
Phase 3: Multi-Angle DIY Sweep    → 6 × assert-sweep-{N}-{angle}.json
Phase 4: Consolidated Report      → assert-sweep-report.md + assert-sweep-tasks.json

Read the full file on GitHub · 166 lines

Files

What ships with it

2 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. 1mo ago First seen · 166 lines · 99 tokens per session scan A 97cb6be42faa

Subscribe to this mod's changes

ring:using-assert is a skill published in the GitHub repository LerianStudio/ring (218 stars, last pushed 7d ago), licensed Apache-2.0. It adds 99 tokens to every session and 1,974 once invoked, about $0.0004 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 2026-09-03.

Related

Other skills, from other repositories

antidote

Stop AI agents from patching symptoms. Use this skill when coding, reviewing, refactoring, auditing, committing fixes, or adding guards, validation, workarounds, or 20+ lines without deleting code.

Avtr99/antidote · 47 tokens

api-audit

API and endpoint integrity audit across 10 dimensions (D1-D10) plus optional contract stability (D11) and optional OWASP API Security Top 10 (D12: BOLA/BOPLA/BFLA, mass assignment, JWT alg-confusion, GraphQL introspection). Covers validation, payloads, pagination, errors, caching, HTTP semantics, waterfalls, rate…

greglas75/zuvo · 135 tokens

debug

Systematic bug investigation with a five-phase framework: reproduce, narrow, diagnose, fix, verify. Supports automated regression bisect via --regression flag. Produces a structured debug report with root cause analysis, regression test, and CQ/Q self-evaluations.

greglas75/zuvo · 55 tokens

performance-audit

Full-stack performance health check across 12 dimensions. Rendering, bundles, assets, API/network, algorithms, memory, database, caching, Web Vitals, backend runtime, concurrency, and framework-specific pathologies. Evidence-based Impact Models with confidence tiers and a prioritized optimization roadmap. Switches…

greglas75/zuvo · 90 tokens

ops

Use this agent when you need to generate operational tooling for a project - admin/monitoring panels, debug mode overlays, or end-user feedback forms.

samibs/skillfoundry · 32 tokens

prune

Use this agent to find and safely remove dead code and duplicate code — unused imports, unused exports, and copy-paste blocks — in any codebase.

samibs/skillfoundry · 34 tokens