agent-builder

agent-builder is a skill for Claude Code, Codex from Rockielab/rockie-codex. It costs 159 tokens per session (3,821 once invoked), scanned A, a copy of agent-builder, Apache-2.0.

A complete process for building a goal-driven software agent from a plain-language goal into a portable Git repository. It covers the agent's tools, rules, safety checks, testing, and handover package.

In plain words
What is it for?
Use it when you want to create an agent that performs a defined job, choose how it runs, add safeguards, test it adversarially, and prepare it for sharing.
Why use it?
It turns an informal idea into a testable agent project and checks it from a fresh, no-memory starting point. This helps find serious problems before the agent is published.

Skill for Claude CodeCodex

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/rockielab/rockie-codex/agent-builder
Any agent
npx skills add Rockielab/rockie-codex --skill agent-builder
Clone the repo
git clone --depth 1 https://github.com/Rockielab/rockie-codex

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 agent-builder

README.md
[![agentmods](https://agentmods.dev/badge/skills/rockielab/rockie-codex/agent-builder.svg)](https://agentmods.dev/skills/rockielab/rockie-codex/agent-builder)
Your own site
<a href="https://agentmods.dev/skills/rockielab/rockie-codex/agent-builder"><img src="https://agentmods.dev/badge/skills/rockielab/rockie-codex/agent-builder.svg" alt="Measured on agentmods" height="20"></a>
Per session 159 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,821 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00159 $0.03821
Opus 5 $0.00079 $0.01911
Sonnet 5 $0.00032 $0.00764
Haiku 4.5 $0.00016 $0.00382

Measured 5d ago against content hash 175f4e37ade4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

agent-builder 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.

The scan reads SKILL.md. This mod also ships 8 executable files (examples/release-notes-writer.bundle/policies-bundle/.claude/hooks/policy_gate.py, examples/release-notes-writer/.claude/hooks/policy_gate.py, examples/release-notes-writer/.claude/skills/self-critic/critic_loop.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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

This is a copy

100% identical to agent-builder — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

project-extension/agents/skills/agent-builder/SKILL.md · 251 lines

How it starts

The opening of the file, as written. The whole thing — 251 lines — stays where its author put it; the contents beside it link to each section on GitHub.

agent-builder — build any goal-declared agent

This skill is the meta-system that generalizes the proven diligence agent ("Atlas") into a reusable pipeline: declare a goal, and out comes a portable, self-hardening, publishable agent. Atlas shipped to prod using the patterns this skill reuses; agent-builder turns those patterns from "build one diligence agent" into "build any agent". You build the builder, not the agent's output.

Explicit goal

Take a user's declared goal ("an agent that does X") and produce a portable git repo on the OpenClaw/Claude-Code harness that achieves it, ships its own adversarial safeguards by default, survives a fresh no-memory publish gauntlet twice with zero CRITICALs before it is allowed to ship, and serializes to a .af agent-file for handover. Refuse to declare an agent publishable until the gate says so.

Lifecycle

[1] DECLARE   — resolve the goal to ONE testable sentence. Ask 2-3 clarifying Qs
                only if it is too vague to test. Write it to agent.config.json.
[2] CHOOSE    — pick runtime/model/tools + write policies/hooks/safeguards.
                The decision table below drives every choice from the goal.
[3] SCAFFOLD  — scripts/scaffold_agent.py emits the portable repo (CLAUDE.md,
                .claude/skills/ incl. the self-adversarial critic BY DEFAULT,
                .claude/hooks/, .mcp.json, policies/, tests/, manifest).
[4] BUILD     — flesh out the domain skills/prompts so it achieves the goal;
                keep the self-critic wired.
[5] RUN       — exercise the agent; produce a sample deliverable.
[6] GATE      — scripts/publish_gate.py: a fresh no-memory adversarial gauntlet.
                quality sublayer ALWAYS; ai-detection sublayer when opted in.
                Counter resets on any failed round.
[7] ITERATE   — apply the cited fixes; re-run. One pass never unlocks.
[8] PUBLISH   — ONLY after two consecutive zero-CRITICAL rounds (publishable:true).
[9] EXPORT    — scripts/af_export.py emits the .af handover artifact.

Read the full file on GitHub · 251 lines

Files

What ships with it

38 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. 5d ago First seen · 251 lines · 159 tokens per session scan A 175f4e37ade4

Subscribe to this mod's changes

agent-builder is a skill published in the GitHub repository Rockielab/rockie-codex (20 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 159 tokens to every session and 3,821 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to agent-builder, differing in 0 lines, and is treated as a copy.

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