Statin

Telemetry for your opencode sessions. opencode-statin records every event the opencode runtime emits — with timestamps — to a JSONL log and keeps per-session statistics: messages by role, parts by type, tool calls and durations, compactions, idle periods, tokens, cost, system-prompt size, and the models in play. Two slash commands surface it: /statin for a session summary and /statin-events for the most recent events plus the log path.

It is read-only: it observes, it never injects anything into a session and never tells the model what to do.

Install

opencode plugin opencode-statin -g

Restart opencode to load the plugin.

opencode plugin only installs the module and adds it to your plugin config — it does not copy command files out of the package. So also register the two slash commands by copying the bundled files into your global commands directory:

cp ~/.cache/opencode/node_modules/opencode-statin/commands/*.md ~/.config/opencode/commands/

From a repo checkout, use cp commands/*.md ~/.config/opencode/commands/ instead. opencode scans both command/ and commands/, in the global config directory and in a project's .opencode/. As an alternative to files, you can declare the commands inline under the command key of opencode.json.

Usage

Command	Effect
/statin	Session statistics: messages, parts, tools, tokens, cost, ...
/statin-events	The last 40 recorded events and the path to the JSONL log

Configure

Create ~/.config/opencode/statin.json (a legacy opencode-statin.json in the same directory is also read):

{
  "logDir": "~/.config/opencode/statin",
  "maxLogBytes": 5242880,
  "ringSize": 5000,
  "logPartUpdated": false,
  "eventLog": false,
  "usageTtlDays": 7
}

Field	Default	Description
logDir	~/.config/opencode/statin	Directory for usage.json (and events.jsonl when eventLog is on)
maxLogBytes	5242880 (5 MiB)	Rotate to events.jsonl.1 once the log grows past this size
ringSize	5000	In-memory ring buffer of recent events
logPartUpdated	false	Also log message.part.updated (very noisy — streaming deltas)
eventLog	false	Write the event telemetry log. Off by default since 0.2.0
usageTtlDays	7	Prune usage.json entries not touched for this many days

Usage tracking

Independently of the event log, the plugin counts read and grep tool calls and persists them to usage.json (same logDir). Each entry is tool:argument -> { count, first, last }, keyed by project (the working directory's basename), so the file can be kept per-machine and compared across machines. read paths are stored relative to the project root — use the counts to spot documentation gaps (files the agent keeps having to read, classes it keeps grepping for) and describe them in docs instead. Entries are pruned after usageTtlDays of inactivity. /statin-events shows the top entries and the file path.

Privacy

events.jsonl (when enabled) and usage.json contain event payload summaries and tool arguments, including fragments of your conversations (titles, message roles, token counts, tool names, file paths, grep patterns). Treat them as sensitive data and keep them out of version control and shared backups.

Development

npm install
npm run typecheck
npm test

License

MIT