# cctop
**An htop for your AI coding agents.** One screen showing every Claude Code,
Codex, Cursor, Gemini CLI, OpenCode, Pi and Windsurf session on your machine —
what each is doing, what it has spent, and which one is waiting on you.
```
Sessions (4/71) $12.64 today · 2 running
LAST DUR $ CTX% CPU% MEM TOOLS ERR% MODEL PERM ! PROJECT
● 3s 1h12m $4.82 68% 22.4 1.2G 178 2% opus-5 edits ⚠ ~/cctop
● 14s 46m $2.10 31% 8.1 840M 94 ─ gpt-5-codex ask ⚠ ~/cctop
● 2m 2h03m $9.41 88% 0.0 1.5G 402 14% opus-5 BYPASS · ~/api
○ 4h 22m $0.31 ─ ─ ─ 31 0% sonnet-5 ─ ─ ~/scripts
Conflict: ⚠ …/ui/mod.rs — 2 agents have written it
```
It reads what the agents leave on disk, so it sees sessions it did not start,
including ones that ended weeks ago. Nothing to configure, nothing to run
alongside it.
A Rust rewrite of an earlier Node implementation.
## Install
```bash
cargo install cctop
```
Or grab a binary for your platform from the
[latest release](https://github.com/flolep2607/cctop/releases/latest):
```bash
# Linux x86_64 (static — works on any distro)
curl -fsSL https://github.com/flolep2607/cctop/releases/latest/download/cctop-x86_64-unknown-linux-musl.tar.gz | tar xz
sudo install -m755 cctop /usr/local/bin/cctop
```
macOS, Windows, checksums and `cctop --update` are in
[Installing cctop](docs/install.md).
## Start here
```bash
cctop
```
That is the whole first run. It finds your sessions, prices them, and draws the
table above.
Four keys are worth knowing before anything else:
| `↑` `↓` | move between sessions |
| `←` `→` | move between the panels underneath |
| `/` | filter, on anything a row is |
| `q` | quit |
Then two commands worth running once:
```bash
cctop --install-hooks # let the agents report their own state, live
cctop doctor # check the installation and say what is wrong with it
```
## What it tells you
**What everything costs.** Tokens times published rates, per session, per hour,
per day, per model. The numbers are estimates and the
[cost page](docs/costs.md) is honest about which providers report real figures
and which are inferred.
**What is in the context window.** `CTX%` says it is 68% full; the Context panel
says what is *in* it — startup, tool output, attachments, and an
Unaccounted bar that never pretends to be smaller than it is. Under it, a chart
of how the window filled across the whole session, compactions included.
See [The bottom panels](docs/panels.md).
**Which session needs you.** The status dot goes amber when an agent is waiting
on input and red on an API error. `w` turns on the terminal bell and a desktop
notification for the moment a session crosses into waiting.
**Which sessions are stuck.** `ERR%` is the share of a session's tool calls that
failed — a quarter of them is an agent retrying something that will not work and
paying for each attempt. Compaction cadence catches the other kind of waste, a
session rebuilding a window it keeps refilling.
**When two agents are about to collide.** Two agents in one checkout is not a
merge conflict — git would announce that. It is one of them writing a file the
other still holds, and the loser finds out when the work is gone. The `!` column
says so first. See [Reading the table](docs/the-table.md#-when-two-agents-are-in-one-repository).
## What it can do
Beyond watching, cctop can answer an agent (`s`), reopen any session in a tab of
its own (`R`), hold several agents side by side, hand a session's context over to
a *different* harness (`O`), and read the sessions on another machine over ssh.
- [Reading the table](docs/the-table.md) — every column, the status dot, filtering, and the full key list
- [Driving agents](docs/driving-agents.md) — typing into sessions, resuming, tabs and splits, notifications, handoff
- [The bottom panels](docs/panels.md) — Tool Activity and the context breakdown
- [What the cost figures mean](docs/costs.md) — how each provider is priced, and where the data comes from
- [Integrations](docs/integrations.md) — agent hooks, the MCP server, and `--host`
- [Troubleshooting](docs/troubleshooting.md) — `cctop doctor` and the usual causes
## Which agents it reads
| Claude Code | estimated | ✓ | ✓ full breakdown | ✓ | ✓ |
| Codex | estimated | ✓ | ✓ | ✓ | ✓ |
| OpenCode | reported | ✓ | ✓ | ✓ | ✓ |
| Pi | reported | ✓ | ─ | ✓ | ✓ |
| Gemini CLI | estimated | ✓ | ─ | ✓ | ─ |
| Cursor | ─ | ─ | ─ | ✓ | inferred |
| Windsurf | ─ | ─ | ─ | ✓ | ─ |
Claude for Mac is read too. A `─` is a gap in what that harness records, not in
cctop — the details are on the [cost page](docs/costs.md).
## A note on cost figures
Most costs are **estimates**: tokens multiplied by published per-token rates.
Subscription plans — Claude Max, Pro, Team — are flat-rate or bundle tokens
differently, so these numbers will not match your invoice. Treat the `$` column
as a measure of resource consumption, not as billing. `--plan max` displays
bundled usage as `incl` instead.
## Usage
```bash
cctop # interactive UI
cctop --list # print a table and exit
cctop --json # dump full session data as JSON
cctop --plan max # treat Claude usage as bundled
cctop --host devbox # also show another machine's sessions, read over ssh
cctop doctor # check this installation and say what is wrong with it
cctop claude # start an agent on a pty cctop can watch and type into
```
`cctop --help` has the rest.
## Contributing
Bug reports and patches welcome — see [CONTRIBUTING.md](CONTRIBUTING.md), which
also has the architecture notes and the things about this codebase that are not
obvious from reading it.
## License
[MIT](LICENSE).