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 skills/shimo4228/claude-harness/spawn-sessionnpx skills add shimo4228/claude-harness --skill spawn-sessiongit clone --depth 1 https://github.com/shimo4228/claude-harnessWrote 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.
[](https://agentmods.dev/skills/shimo4228/claude-harness/spawn-session)<a href="https://agentmods.dev/skills/shimo4228/claude-harness/spawn-session"><img src="https://agentmods.dev/badge/skills/shimo4228/claude-harness/spawn-session.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00197 | $0.03889 |
| Opus 5 | $0.00098 | $0.01945 |
| Sonnet 5 | $0.00039 | $0.00778 |
| Haiku 4.5 | $0.00020 | $0.00389 |
Grade B, and why
spawn-session scanned grade B with 1 finding 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 4d 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.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
- **Dispatch で足りる用件** → Cowork タブの Dispatch に投げると、開発作業なら **Code タブのセッション**が起きる（Dispatch バッジ付きでサイドバーに出る）。**`~/.claude` の設定系は読まれる** — personal skills in `~/.claude/skills/` は local session に効き、`~/.claude/settings.json` も D How it starts
The opening of the file, as written. The whole thing — 129 lines — stays where its author put it; the contents beside it link to each section on GitHub.
spawn-session
生きている任意のセッションから、名前付き・detached な新しい Claude Code Remote Control セッションを Herdr 内に起動する。新セッションは自分の RC を登録するので Claude モバイルアプリのセッション一覧に出る。iPhone から Remote Control 越しに操作している最中に、Mac に触れず別プロジェクトのセッションを増やすのが主用途。Herdr の艦隊ビュー（サイドバー・agent status）にもそのまま並ぶ。
When to use
- 新しいセッションが欲しい（多くは別プロジェクト用）でモバイルアプリ一覧に出したい
- トリガー例: 「新しいセッション立てて」「AAP のセッション開いて」「spawn a session for X」/
/spawn-session [project]
When NOT to use
- 既存の会話を続けたい →
claude --continue/--resume - 現在のセッションの文脈を消したいだけ →
/clear - 現在のセッションの model / effort 切替 →
/model,--effort - 同じ repo で複数セッションが欲しいだけ → 公式 server mode（
claude remote-control --spawn worktree --capacity N）で足りる。この skill は要らない - Dispatch で足りる用件 → Cowork タブの Dispatch に投げると、開発作業なら Code タブのセッションが起きる（Dispatch バッジ付きでサイドバーに出る）。
~/.claudeの設定系は読まれる — personal skills in~/.claude/skills/は local session に効き、~/.claude/settings.jsonも Desktop と共有される（設定が claude.ai 同期になるのは Cowork タブ側の skills / plugins / connectors であって Code セッションではない）。この skill を使う理由は設定の届き方ではなく、Desktop アプリが実行主体になり Herdr 艦隊ビューに並ばないことと、起こす repo をこちらが選べないこと（Dispatch が種別で振り分ける）。Pro/Max 限定で Team/Enterprise では使えない - cloud session（Claude Code on the web）→ Anthropic 側で実行されるので、ローカル FS / MCP / Herdr と無関係。手元の repo を触らせたいなら対象外
How it works
埋めているギャップは cwd の壁であって、セッション数の壁ではない（2026-08-01 に公式 docs で確認）。公式 Remote Control には server mode があり --spawn <same-dir|worktree|session> / --capacity <N>（既定 32）/ --[no-]create-session-in-dir で 1 プロセスから複数セッションを持てる。ただし server mode の全セッションはその server プロセスの cwd（= 1 repo）に縛られる — same-dir は cwd 共有、worktree はその repo の worktree。別プロジェクトのセッションを起こす手段が公式には無い。回避策: 生きている任意のセッションが Bash で別の claude --remote-control "<名前>" を、指定した repo の cwd で Herdr の pane 内に detached 起動する。新プロセスが自分の RC を登録し、アプリ一覧に出る。Herdr の persistent session（server）が pty を保持するので、Ghostty/SSH の切断や起動元セッションの終了後も生き残る。server が動いていなければ spawn.sh が headless server を自動起動する（tmux のサーバー自動起動と同等のセマンティクス）。
配置は repo 単位 workspace 運用に合わせる: 同じルート（cwd）の workspace が既にあればそこに新 tab、無ければ新 workspace を作成（workspace label は repo 名、表示名は tab label）。
What ships with it
1 file 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.
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.
- 4d ago First seen · 129 lines · 197 tokens per session scan B 89a6de516395
spawn-session is a skill published in the GitHub repository shimo4228/claude-harness (2 stars, last pushed 5d ago), licensed MIT. It adds 197 tokens to every session and 3,889 once invoked, about $0.0010 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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