oc-update-skill

oc-update-skill is a skill for Claude Code, Codex from sequenzia/agent-alchemy. It costs 65 tokens per session (1,345 once invoked), scanned A, original, MIT.

A command for updating an OpenCode skill, a set of instructions that guides an AI coding tool. It locates the skill, checks it against current platform guidance, applies changes, and validates the result.

In plain words
What is it for?
Use it to find an existing skill, review outdated instructions, migrate it to current OpenCode practices, and verify the updated file.
Why use it?
It helps bring an older skill up to date when platform conventions or supported patterns have changed.

Skill for Claude CodeCodex

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the agent-alchemy-opencode-tools plugin — 7 skills, 3 agents shipped together

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.

agentmods
npx agentmods add skills/sequenzia/agent-alchemy/oc-update-skill
Any agent
npx skills add sequenzia/agent-alchemy --skill oc-update-skill
Clone the repo
git clone --depth 1 https://github.com/sequenzia/agent-alchemy

Made for: Claude Code, Codex.

Or install agent-alchemy-opencode-tools, the plugin that ships this one along with the rest of its 7 skills, 3 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 oc-update-skill

README.md
[![agentmods](https://agentmods.dev/badge/skills/sequenzia/agent-alchemy/oc-update-skill.svg)](https://agentmods.dev/skills/sequenzia/agent-alchemy/oc-update-skill)
Your own site
<a href="https://agentmods.dev/skills/sequenzia/agent-alchemy/oc-update-skill"><img src="https://agentmods.dev/badge/skills/sequenzia/agent-alchemy/oc-update-skill.svg" alt="Measured on agentmods" height="20"></a>
Per session 65 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,345 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00065 $0.01345
Opus 5 $0.00032 $0.00673
Sonnet 5 $0.00013 $0.00269
Haiku 4.5 $0.00006 $0.00135

Measured 5d ago against content hash 04b6eb9cc313, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

oc-update-skill 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 5d 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.

claude/opencode-tools/skills/oc-update-skill/SKILL.md · 183 lines

How it starts

The opening of the file, as written. The whole thing — 183 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Update OpenCode Skill

You are initiating the OpenCode skill update workflow. This process locates an existing skill, researches current platform best practices, analyzes the skill for outdated patterns, and applies updates with validation.

Critical Rules

AskUserQuestion is MANDATORY

IMPORTANT: You MUST use the AskUserQuestion tool for ALL questions to the user. Never ask questions through regular text output.


Phase 1: Load References

Read the OpenCode platform overview and skill guide:

  1. Read ${CLAUDE_PLUGIN_ROOT}/references/platform-overview.md
  2. Read ${CLAUDE_PLUGIN_ROOT}/references/skill-guide.md

Phase 2: Locate Skill

Find the skill to update.

If $ARGUMENTS is provided:

  1. Check if the argument is a file path — read it directly
  2. If it's a skill name — search for it in known discovery paths

If no arguments:

  1. Search for OpenCode skills in the workspace:
    • Glob for .opencode/skills/*/SKILL.md
    • Glob for .claude/skills/*/SKILL.md
    • Glob for .agents/skills/*/SKILL.md
  2. Present found skills using AskUserQuestion:
    • Header: "Select Skill"
    • Question: "Which skill would you like to update?"
    • Options: List found skills (up to 4; include "Other" for custom path)

Read the selected skill file and store its contents.


Phase 3: Research

Spawn the researcher agent to check latest OpenCode documentation:

Task:
  subagent_type: "agent-alchemy-opencode-tools:oc-researcher"
  prompt: |
    Research the latest OpenCode documentation for skill format compatibility.

    Artifact type: skill
    Current artifact content:
    ---
    {contents of the skill file}
    ---

    Specific questions:
    1. Are there any new skill frontmatter fields since v1.2.10?
    2. Have any existing fields been deprecated?
    3. Are there new best practices for skill body structure?
    4. Any changes to $VARIABLE placeholder handling?

    Reference guide: ${CLAUDE_PLUGIN_ROOT}/references/skill-guide.md

Read the full file on GitHub · 183 lines

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. 5d ago First seen · 183 lines · 65 tokens per session scan A 04b6eb9cc313

Subscribe to this mod's changes

oc-update-skill is a skill published in the GitHub repository sequenzia/agent-alchemy (43 stars, last pushed 3mo ago), licensed MIT. It adds 65 tokens to every session and 1,345 once invoked, about $0.0003 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

claude-code-session-broker

Use when running Arcgentic V2 in Claude Code and fixed Planner, Developer, and Auditor role sessions must be coordinated through a broker.

Arch1eSUN/Arcgentic · 35 tokens

arcgentic

Use when the user says Arcgentic, asks to use Arcgentic, or wants an idea taken through a complete plan → development → self-audit → external audit workflow in Codex.

Arch1eSUN/Arcgentic · 43 tokens

espalier-migrate

Migrate an existing harness/espalier install to the current Espalier version — auto-detects which of v0.1→v0.2, v0.3→v0.4, v0.4→v0.5, the v0.5.3 coder-agent patch, v0.5→v0.6 (Stage 1 grill), v0.6→v0.7 (read-only /espalier-ask lane), v0.7→v0.8 (requirements approval gate), the v0.8.1 impact-analysis agent patch, the…

Junhanliu-dev/espalier-engineering · 0 tokens

session-mode

Use when a project has not yet stored session mode, when a user asks for complete arcgentic workflow execution, or when role identity handoff prompts are needed.

Arch1eSUN/Arcgentic · 36 tokens

verify-gates

Runs the mechanical quality gates that the arcgentic state machine requires for state transitions. Invoked indirectly by transition.sh OR directly by orchestrator agent before declaring a state transition. Use when about to call transition.sh OR when manually verifying that a round artifact meets the gate criteria.…

Arch1eSUN/Arcgentic · 75 tokens

cross-session-handoff

Read, write, snapshot, and lock .arcgentic/state.yaml across planner, dev, audit, and optional test sessions.

Arch1eSUN/Arcgentic · 31 tokens