test-writer

test-writer is an agent for Claude Code from Robo-Co-op/robobuilder-standard. It costs 44 tokens per session (356 once invoked), scanned A, original, no licence file.

A test-coverage auditor and test generator for recently changed files.

In plain words
What is it for?
Use it after adding a feature or fixing a bug to flag missing high-priority tests and generate them.
Why use it?
It finds important cases that the current tests do not cover before a change is reviewed.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the robobuilder plugin — 41 skills, 9 agents, 6 hooks shipped together

Good fit Use it after adding a feature or fixing a bug to flag missing high-priority tests and generate them.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/robo-co-op/robobuilder-standard/test-writer
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.

Clone the repo
git clone --depth 1 https://github.com/Robo-Co-op/robobuilder-standard

Made for: Claude Code.

Or install robobuilder, the plugin that ships this one along with the rest of its 41 skills, 9 agents, 6 hooks.

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 test-writer

README.md
[![agentmods](https://agentmods.dev/badge/agents/robo-co-op/robobuilder-standard/test-writer.svg)](https://agentmods.dev/agents/robo-co-op/robobuilder-standard/test-writer)
Your own site
<a href="https://agentmods.dev/agents/robo-co-op/robobuilder-standard/test-writer"><img src="https://agentmods.dev/badge/agents/robo-co-op/robobuilder-standard/test-writer.svg" alt="Measured on agentmods" height="20"></a>
Per session 44 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 356 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 unknown 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 $0.00044 $0.00356
Opus 5 $0.00022 $0.00178
Sonnet 5 $0.00009 $0.00071
Haiku 4.5 $0.00004 $0.00036

Measured 8d ago against content hash fefc714b3393, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

test-writer 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 8d 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.

agents/test-writer.md · 43 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 8d ago First seen · 43 lines · 44 tokens per session scan A fefc714b3393

Subscribe to this mod's changes

test-writer is an agent published in the GitHub repository Robo-Co-op/robobuilder-standard (2 stars, last pushed 11d ago), with no licence file. It adds 44 tokens to every session and 356 once invoked, about $0.0002 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 2026-08-31.

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