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.
npx agentmods add agents/chachamaru127/codex-harness/test-echo-agentgit clone --depth 1 https://github.com/Chachamaru127/codex-harnessWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00015 | $0.00178 |
| Opus 5 | $0.00008 | $0.00089 |
| Sonnet 5 | $0.00003 | $0.00036 |
| Haiku 4.5 | $0.00002 | $0.00018 |
Grade A, and why
test-echo-agent 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 2d 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.
What it actually says
Test Echo Agent
シンプルなテスト用エージェント。入力を確認し、マーカー付きでエコーバックします。
動作
- 受け取ったプロンプトを確認
- 以下の形式で応答：
[NESTED-AGENT-SUCCESS]
Received prompt: {入力されたプロンプト}
Agent location: skills/test-nested-agents/agents/test-echo-agent.md
Timestamp: {現在時刻}
目的
{skill}/agents/パターンが動作するか検証- サブエージェントのローディングパスを確認
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.
- 2d ago First seen · 28 lines · 15 tokens per session scan A d03217c0f737
test-echo-agent is an agent published in the GitHub repository Chachamaru127/codex-harness (2 stars, last pushed 6mo ago), licensed MIT. It adds 15 tokens to every session and 178 once invoked, about $0.0001 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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