Borrowing it
Nothing to install: this file belongs to Chachamaru127/codex-harness. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Chachamaru127/codex-harness/main/.codex/skills/session/SKILL.mdgit clone --depth 1 https://github.com/Chachamaru127/codex-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/chachamaru127/codex-harness/session)<a href="https://agentmods.dev/skills/chachamaru127/codex-harness/session"><img src="https://agentmods.dev/badge/skills/chachamaru127/codex-harness/session/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/chachamaru127/codex-harness/session"><img src="https://agentmods.dev/badge/skills/chachamaru127/codex-harness/session.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00057 | $0.01484 |
| Opus 5.5 | $0.00023 | $0.00594 |
| Sonnet 5.5 | $0.00011 | $0.00297 |
| Haiku 4.5 | $0.00006 | $0.00148 |
Grade A, and why
session 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 191 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Session Skill (Unified)
Consolidates all session-related functionality into one skill.
Usage
/session # Show available options
/session list # Show active sessions
/session inbox # Check incoming messages
/session broadcast "message" # Send message to all sessions
Subcommands
/session list - List Active Sessions
Shows all active Claude Code sessions in the current project.
📋 Active Sessions
| Session ID | Status | Last Activity |
|------------|--------|---------------|
| abc123 | active | 2 min ago |
| def456 | idle | 15 min ago |
/session inbox - Check Inbox
Checks for incoming messages from other sessions.
📬 Session Inbox
| From | Time | Message |
|------|------|---------|
| abc123 | 5m ago | "Ready for review" |
| def456 | 10m ago | "API implementation done" |
/session broadcast "message" - Broadcast Message
Sends a message to all active sessions.
/session broadcast "Review complete, ready for merge"
Capabilities
| Feature | Description | Reference |
|---|---|---|
| Initialization | Start new session, load context | See ../session-init/SKILL.md |
| Memory | Persist learnings across sessions | See ../session-memory/SKILL.md |
| State Control | Resume/fork session based on flags | See references/session-control.md |
| Communication | Cross-session messaging | See ../session-state/SKILL.md |
メモリ最適化（CC 2.1.38+）
Claude Code 2.1.38 以降、セッション再開時のメモリ使用量が 68% 削減 されました。
長時間セッション管理のベストプラクティス
| ワークロード | 推奨戦略 |
|---|---|
| 通常実装 | 1-2時間ごとに --resume で再開 |
| 大規模リファクタ | 機能単位でセッション分割 → 各セッションで --resume |
| 並列タスク | /work all で並列実行、長時間なら途中で --resume |
| メモリ警告時 | 即座に --resume で再開（以前より高速） |
セッション名の自動生成（CC 2.1.41+）
/rename を引数なしで実行すると、会話コンテキストからセッション名を自動生成します。
長時間セッションや --resume を多用するワークフローでセッションの識別が容易になります。
What ships with it
4 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.
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.
- 1mo ago First seen · 191 lines · 57 tokens per session scan A 7ec2e9293718
session is a skill published in the GitHub repository Chachamaru127/codex-harness (2 stars, last pushed 8mo ago), licensed MIT. It adds 57 tokens to every session and 1,484 once invoked, about $0.0002 per session on Opus 5.5. 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.
Other skills, from other repositories
knowledge-ingest
Ingest documents, articles, conversations, or supplied text into Knowledge with retained originals, sourced claims, entity updates, timelines, and cross-links; also learn durable lessons from a set of conversations, transcripts, or past sessions (/learn), including the Learn from conversations and Learn from Memory…
mem0-oss-to-platform
Plan, then execute, a migration of a project from the mem0 open-source / self-hosted SDK (local Memory class) to the mem0 Platform / hosted SDK (MemoryClient). TRIGGER when: the developer wants to move, switch, or migrate mem0 off OSS/self-hosted to the hosted API, e.g. "migrate my mem0 setup to the platform", "switch…
forget
Remove a personal fact, preference, relationship detail, topic, or prior event from Muse's active memory and stop existing copies or automations from bringing it back. Use for explicit requests such as 'forget that', 'don't remember this about me', or 'remove that from your memory'. Do not use when 'forget it' merely…
Cortex
LifeOS memory, prior-session recall, and learning capture. USE WHEN capture this learning, document this learning, what did we learn recently, recent learnings, cortex, knowledge, knowledge base, search knowledge, what do we know about, archive, harvest, knowledge status, develop note, add to knowledge, add a people…
memory
Use when the user asks to remember, recall, forget, update, search, or inspect durable OpenSquilla memory, including profile facts in USER.md and long-term notes in MEMORY.md or memory//.md.
ha-data-stores
Map of Hope Agent's local data stores and safe read-only query workflow. Use when the user asks where Hope Agent stores data, wants to inspect sessions/messages/memory/logs/background jobs/knowledge indexes/settings, asks the model to query local app data, or debugging requires checking persisted state. Trigger…