Borrowing it
Nothing to install: this file belongs to StefanoGuerrini/c9s. 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/StefanoGuerrini/c9s/main/CLAUDE.mdgit clone --depth 1 https://github.com/StefanoGuerrini/c9sWrote 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/instructions/stefanoguerrini/c9s/claude-md)<a href="https://agentmods.dev/instructions/stefanoguerrini/c9s/claude-md"><img src="https://agentmods.dev/badge/instructions/stefanoguerrini/c9s/claude-md/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/instructions/stefanoguerrini/c9s/claude-md"><img src="https://agentmods.dev/badge/instructions/stefanoguerrini/c9s/claude-md.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 | $0.02256 | $0.02256 |
| Opus 5.5 | $0.00902 | $0.00902 |
| Sonnet 5.5 | $0.00451 | $0.00451 |
| Haiku 4.5 | $0.00226 | $0.00226 |
Grade A, and why
c9s CLAUDE.md 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 2mo 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 — 183 lines — stays where its author put it; the contents beside it link to each section on GitHub.
c9s — Claude Code Dashboard
A simple terminal dashboard for Claude Code. Run c9s, see all your projects and sessions, create new ones, attach to running ones. Zero setup — it reads directly from ~/.claude/.
Inspired by k9s: simple, fast, keyboard-driven.
Vision
- Dashboard-first: Launch c9s → see all your Claude Code projects and sessions across all directories
- Zero setup: Discovers existing sessions from
~/.claude/history.jsonland~/.claude/projects/ - tmux for sessions: Real interactive Claude Code terminals via tmux windows (no in-process terminal emulator)
- Simple: One binary + tmux. No daemon, no plugins, no agent mail. Just a dashboard.
- Future: Extend to other CLI agents (Codex, Gemini) — but Claude Code first.
Data sources (all local, no API)
| What | Where |
|---|---|
| All sessions + projects | ~/.claude/history.jsonl |
| Token usage per session | ~/.claude/projects/<path>/<session>.jsonl → sum message.usage |
| Session name/title | sessions-index.json → customTitle, or history.jsonl → display |
| Session status | JSONL file mtime + ps/lsof process detection |
Testing
Always write tests for every change. No code lands without corresponding test coverage.
- Tests live next to the code they test (
foo_test.goalongsidefoo.go) - Run all tests:
go test ./... -count=1 - Run a specific package:
go test ./internal/claude/ -v - Use
t.TempDir()for any file I/O in tests — never write to real paths - Table-driven tests preferred for functions with multiple input/output cases
- Test both happy paths and edge cases (missing files, empty inputs, etc.)
Architecture
c9s/
├── main.go # Bubbletea TUI + tmux bootstrap + keybindings
├── internal/
│ ├── claude/
│ │ ├── sessions.go # Session discovery, token reading, process detection
│ │ └── sessions_test.go # Tests
│ ├── config/
│ │ ├── config.go # Config loading from ~/.c9s/config.json
│ │ └── config_test.go # Tests
│ ├── git/
│ │ ├── worktree.go # Git worktree discovery + creation
│ │ └── worktree_test.go # Tests
│ └── tmux/
│ ├── tmux.go # tmux CLI wrapper, pane status, status bar
│ ├── tmux_test.go # Tests
│ ├── exec_unix.go # syscall.Exec (Unix)
│ └── exec_windows.go # Stub (Windows)
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.
- 2mo ago First seen · 183 lines · 2,256 tokens per session scan A ea17fcb0a5dc
c9s CLAUDE.md is an instructions file published in the GitHub repository StefanoGuerrini/c9s (7 stars, last pushed 2mo ago), licensed MIT. It adds 2,256 tokens to every session, about $0.0090 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.
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