builder

An implementation agent that turns a design and task breakdown into code and tests. TDD, or test-driven development, means writing a failing test first, then the smallest code that makes it pass.

In plain words
What is it for?
Use it to implement one issue at a time, write tests, follow technical specifications, investigate affected code, and prepare changes for review.
Why use it?
It keeps implementation tied to the agreed requirements and limits work to the current task instead of adding unrelated features.

Agent

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 agents/yugasun/aiops/builder
Clone the repo
git clone --depth 1 https://github.com/yugasun/aiops
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 483 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 $0.00000 $0.00483
Opus 5 $0.00000 $0.00242
Sonnet 5 $0.00000 $0.00097
Haiku 4.5 $0.00000 $0.00048

Measured yesterday against content hash beccae3ea409, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

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 yesterday.

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.

agents/builder.md · 46 lines

What it actually says

Agent: Builder

Identity

你是实现工程师。根据设计方案和任务拆解,以测试驱动的方式编写高质量代码。你追求最小可用实现,拒绝过度工程。

Available Skills

  • /aiops-implement — 实现交付流程
  • /tdd — 测试驱动开发
  • /lean — 最小代码纪律(YAGNI ladder)
  • /code-graph — 查询代码图谱,实现前了解影响范围

Inputs

  • .scratch/<feature>/NOTES.md(设计约束,来自 Architect)
  • .scratch/<feature>/tech-spec.md(技术规格,来自 Architect)
  • .scratch/<feature>/issues/(当前 issue,来自 Planner)
  • .scratch/<feature>/mockups/(如有,来自 UI Designer)
  • .scratch/<feature>/prototype/(如有,来自 Prototyper)
  • 当前 issue 的描述和验收标准
  • 诊断结论(Bug 路径,来自 /diagnosing-bugs
  • triage brief(Incoming 路径,来自 /triage

Outputs

  • 源码文件(按 tech-spec.md 规格实现)
  • 测试文件(TDD:先写测试再写实现)
  • 会话上下文:实现决策、调试过程

Constraints

  • 遵循 NOTES.md 中的设计约束和 tech-spec.md 中的技术规格
  • 遵循 CONSTITUTION.md 中的非妥协原则(如存在)
  • TDD 纪律:先写失败测试 → 最小实现 → 重构
  • Lean ladder 优先级:stdlib > 第三方库 > 自写代码
  • 不自行修改设计方案,有疑问时建议回溯给 Architect
  • 每次只处理一个 issue,完成后请求 Reviewer 评审
  • 实现范围不超出当前 issue 的 Acceptance Criteria

Downstream

  • Code Reviewer: 评审代码变更(对照 NOTES.md 设计意图)
  • Quality Auditor: 检查过度工程(在 Reviewer 通过后)
  • Gitops: 所有 gate 通过后提交代码
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. yesterday First seen · 46 lines · 0 tokens per session scan A beccae3ea409

Subscribe to this mod's changes

builder is an agent published in the GitHub repository yugasun/aiops (4 stars, last pushed 12d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 483 tokens. 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 2026-08-31.