cost-track

Original：🇺🇸 English

Translated

Auto-capture per-session token usage from the Claude Code session jsonl and persist to the cost-tracking namespace

4installs

Sourceruvnet/ruflo

Added on2026-05-09

NPX Install

npx skill4agent add ruvnet/ruflo cost-track

SKILL.md Content

View Translation Comparison →

Cost Track

Reads the active Claude Code session jsonl (

~/.claude/projects/<encoded-cwd>/<session>.jsonl

), tallies assistant-message

usage

per model, computes USD cost using REFERENCE.md pricing, and writes a structured record to the

cost-tracking

AgentDB namespace. This is the producer that gives

cost-report

and

cost-optimize

real data to consume.

When to use

After a meaningful chunk of work, to capture spend for the report.
At session-end to persist the final tally.
Periodically during long sessions (cron-friendly — see
```
/loop 30m
```
).

Steps

Run the tracker from the project root:
bash
```
node plugins/ruflo-cost-tracker/scripts/track.mjs
```
The script auto-discovers the session jsonl from the current working directory. To pin a specific session:
```
TRACK_SESSION=/path/to/session.jsonl
```
. To dry-run (no memory write):
```
TRACK_DRY_RUN=1
```
.
Inspect the markdown summary — total cost, per-model and per-tier breakdowns, and the persisted memory key.

Verify persistence —

mcp__claude-flow__memory_search --query "session-" --namespace cost-tracking

should list the new record.

cost-report

step 1 reads from this namespace.

Record shape (in

cost-tracking

namespace)

Key:

session-<sessionId>

. Value (JSON):

json

{
  "sessionId": "1dba3b8c-...",
  "cwd": "/Users/cohen/Projects/ruflo",
  "startedAt": "2026-05-04T...",
  "endedAt": "2026-05-05T...",
  "messageCount": 234,
  "byModel": {
    "claude-opus-4-7": {
      "tier": "opus",
      "input_tokens": 12345,
      "output_tokens": 6789,
      "cache_creation_input_tokens": 800000,
      "cache_read_input_tokens": 2000000,
      "messages": 50,
      "cost_usd": 1.23
    }
  },
  "byTier": { "haiku": 0.0, "sonnet": 0.45, "opus": 1.23, "unknown": 0 },
  "total_cost_usd": 1.68,
  "capturedAt": "2026-05-05T..."
}

Pricing source of truth

The script's

PRICING

constant mirrors REFERENCE.md "Model pricing (USD per 1M tokens)". Update both together when prices change. Cache-write tokens are billed at

cache_write

rate; cache-read tokens at

cache_read

(per Anthropic billing docs).

Env overrides

Env	Default	Purpose
`TRACK_CWD`	`process.cwd()`	Override which project's sessions to scan
`TRACK_SESSION`	most-recent jsonl	Pin a specific session file
`TRACK_OUT`	unset	Also write the JSON summary to this path
`TRACK_DRY_RUN=1`	unset	Skip the `memory store` call
`TRACK_QUIET=1`	unset	Suppress markdown output
`TRACK_NAMESPACE`	`cost-tracking`	Override target namespace

Cross-references

```
cost-report
```
(consumer) — reads records produced by this skill
REFERENCE.md "Cost attribution formula" — the math the script implements
```
cost-budget-check
```
(consumer; landing in P2) — reads totals to evaluate alerts