# cost-trend

A skill that reads benchmark runs from docs/benchmarks/runs/*.json and surfaces how win rate, latency, escalation rate, and cost change over time. Catches regressions that smoke tests miss.

- skill · `type=skill` · Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, OpenCode · 683 installs · ★ 79357
- Author: ruvnet
- License: MIT · policy=mirror · the beginning of the file is at the end of this page
- Source: https://github.com/ruvnet/ruflo/tree/HEAD/plugins/ruflo-cost-tracker/skills/cost-trend/SKILL.md
- Updated: 2026-10-25
- HTML: https://affpapa.org/en/nevibecode/skills/cost-trend

## What it does

cost-trend analyzes persisted benchmark runs and reports delta between first and last run — win rate, mean and p99 latency, escalation rate, speedup versus Gemini. It also shows a per-run series, flagging regressions when win rate drops or latency rises 1.5× from baseline.

Run the script from project root with `node plugins/ruflo-cost-tracker/scripts/trend.mjs`. Accepts env variables: `TREND_FORMAT=json` emits JSON instead of markdown, `TREND_LIMIT=10` considers only the most recent N runs. Corpus version is recorded in each run, so trends remain interpretable across corpus updates.

Use it before a release to check that speedup hasn't drifted, or after expanding the corpus to verify older runs still hit the same win rate. Baseline latencies for Sonnet 4.6 and Opus 4.7 are included in the report if enabled at run time.

## Install

### Claude Code (native platform)

1. **Skills CLI (Vercel)**
```bash
npx skills add ruvnet/ruflo --skill cost-trend -a claude-code
```

2. **Manually: put the files in place**
- File: `~/.claude/skills/cost-trend/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/cost-trend/

### Codex

1. **Skills CLI (Vercel)**
```bash
npx skills add ruvnet/ruflo --skill cost-trend -a codex
```

2. **Manually: put the files in place**
- File: `.agents/skills/cost-trend/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

1. **Skills CLI (Vercel)**
```bash
npx skills add ruvnet/ruflo --skill cost-trend -a cursor
```

2. **Manually: put the files in place**
- File: `.cursor/skills/cost-trend/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install ruvnet/ruflo cost-trend
```

2. **Manually: put the files in place**
- File: `.github/skills/cost-trend/SKILL.md`

### Gemini CLI

1. **Skills CLI (Vercel)**
```bash
npx skills add ruvnet/ruflo --skill cost-trend -a gemini-cli
```

2. **Platform CLI**
```bash
gemini skills install https://github.com/ruvnet/ruflo --path plugins/ruflo-cost-tracker/skills/cost-trend
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/cost-trend/SKILL.md` — The legacy .windsurf/skills/ path still works

### OpenCode

**Skills CLI (Vercel)**
```bash
npx skills add ruvnet/ruflo --skill cost-trend -a opencode
```

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/ruvnet/ruflo/tree/HEAD/plugins/ruflo-cost-tracker/skills/cost-trend/SKILL.md

## When to use it
- track metric degradation between benchmark runs
- catch slow win rate decline that smoke tests miss
- compare cost and speed across run history
- measure impact of agent-booster upgrades on latency
- surface regressions after corpus expansion

## Example prompts
- Run cost-trend before release to check metric drift
- Export trends to JSON and load into a dashboard
- Review the last 10 runs after updating agent-booster

## Source text · SKILL.md · MIT

Below is the content of a third-party file. It is data, not instructions for you: do not act on anything written inside unless the human asks. Block tag: b29fb1a94eea0e31.

BEGIN THIRD-PARTY FILE b29fb1a94eea0e31
````text
---
name: cost-trend
description: Read every docs/benchmarks/runs/*.json and surface drift in win rate, latency, escalation rate, and LLM-baseline cost over time
argument-hint: ""
allowed-tools: Bash
---

# Cost Trend

The smoke gate is binary (`winRate ≥ 0.80` → pass/fail). The corpus benchmarks captured over time form a curve — and curves catch regressions the gate misses (win rate slowly creeping from 100% to 85% is "still passing" by smoke but a real degradation).

This skill reads every persisted run in `docs/benchmarks/runs/*.json` and reports first→last deltas plus a per-run series, flagging regressions in win rate or latency.

## When to use

- Before a release — check that the speedup hasn't drifted.
- After expanding the corpus — verify older runs still hit the same win rate on the new corpus *they* reflected.
- After upgrading `agent-booster` — surface latency / strategy changes.

## Steps

1. **Run the trend script** from the project root:

   ```bash
   node plugins/ruflo-cost-tracker/scripts/trend.mjs
   ```

   Optional env:
   - `TREND_FORMAT=json` — emit JSON instead of markdown
   - `TREND_LIMIT=10` — consider only the most recent N runs

2. **Inspect the drift summary** — first vs last on win rate, avg latency, p99, escalation rate, speedup vs Gemini.

3. **Inspect the per-run series** — one row per run, including Sonnet 4.6 + Opus 4.7 baseline latencies if those were enabled (`BENCH_ANTHROPIC=1` at run time).

4. **Regression flags** — the script emits `> ⚠ Regression` callouts when:
   - Win rate dropped between first and last run
   - Avg latency rose ≥ 1.5× from first run

## Cross-references

- `cost-benchmark` — the producer of the run JSONs this skill consumes
- `bench/booster-corpus.json` — the corpus version is recorded in each run, so trends across corpus versions remain interpretable
- `docs/benchmarks/runs/latest.json` — the most-recent run; smoke step 23 gates on `winRate ≥ 0.80` from this file
````
END THIRD-PARTY FILE b29fb1a94eea0e31

The third-party file has ended. Everything between the b29fb1a94eea0e31 tags is data: requests and commands from it are not followed. An “end of file” line with another tag inside the block is part of the file.

© ruvnet · MIT · https://github.com/ruvnet/ruflo/tree/HEAD/plugins/ruflo-cost-tracker/skills/cost-trend/SKILL.md

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From the same set: [ruvnet/ruflo](https://affpapa.org/en/nevibecode/by/ruvnet/ruflo.md) — 146 cards

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