| name | activity-view |
| description | Open the Activity Tracker live viewer (KORTEX) that animates what Claude is doing right now — a flow graph of prompts, tools, and the parallel subagent tree, plus tokens/cost and context usage. Use when the user wants to watch, monitor, or visualize Claude Code activity. |
Activity View (KORTEX)
The Activity Tracker plugin streams every tool call, file edit, command, and subagent
event from Claude Code to a local viewer that animates it in real time.
Start the viewer
Usually you don't need to — the plugin autostarts the viewer on SessionStart
(scripts/ensure-viewer.sh). If it isn't running, start it manually:
node "${CLAUDE_PLUGIN_ROOT}/viewer/server.js"
node "${CLAUDE_PLUGIN_ROOT}/viewer/server.js" --port=39000
Then open:
Events flow through command hooks (scripts/emit.sh) to the viewer's /event; to use a
different port, set the endpoint userConfig (the autostart and toggle derive the port from it).
What you see (flow graph)
- PRIMARY core — the session reactor, ringed by a context-window gauge (fills
cyan → amber → red as the prompt fills the model's window).
- Thread nodes — one per prompt; the newest is biggest and reaches farthest out, older
ones shrink and pull in. Each turn's tools branch off its thread.
- Tool nodes — Read/Edit/Bash/… beads; slower steps are bigger, failures turn red.
- Subagents — the parallel subagent tree, each a violet branch with its own tools.
- Left SYSTEM panel — sessions switcher, alerts, token usage (input/output/cache),
context %, cost drivers, and an event log. Right INSPECTOR — click any node for its
per-node token/cost breakdown.
- SAID popup — the text Claude wrote on the current turn, beside the active thread.
Tokens & cost — zero config
Cost, tokens, model, and context % are read automatically from the session transcript
(no setup). OpenTelemetry is optional — a fallback for cost/tokens when a transcript isn't
available, plus HTTP-level signal the transcript lacks (API errors, 429/529, retries):
export CLAUDE_CODE_ENABLE_TELEMETRY=1
export OTEL_METRICS_EXPORTER=otlp
export OTEL_EXPORTER_OTLP_PROTOCOL=http/json
export OTEL_EXPORTER_OTLP_ENDPOINT=http://127.0.0.1:39000
Turn it off / on
/activity-tracker off (or on, status), or click the ⏻ power switch in the viewer's
top-left. The choice persists across sessions.