competitor-monitor

competitor-monitor is a skill for Claude Code, Codex from aeonfun/aeon. It costs 52 tokens per session (3,394 once invoked), scanned A, original, MIT.

A monitoring tool that captures important signals from competitor web pages and compares each visit with the previous snapshot. It checks items such as prices, headings, buttons, links, page metadata, and added or removed pages.

In plain words
What is it for?
Use it to watch selected competitor pages, track changes over time, rank changes by importance, and add new pages to the watch list.
Why use it?
It shows meaningful website changes without requiring someone to reread every monitored page.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is node scripts/competitor-monitor.mjs snapshot <url1> <url2> ... --out "memory/competitor-monitor/${STAMP}.json".

Good fit Use it to watch selected competitor pages, track changes over time, rank changes by importance, and add new pages to the watch list.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/aeonfun/aeon
agentmods
npx agentmods add skills/aeonfun/aeon/competitor-monitor

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for competitor-monitor

README.md
[![agentmods](https://agentmods.dev/badge/skills/aeonfun/aeon/competitor-monitor/github.svg)](https://agentmods.dev/skills/aeonfun/aeon/competitor-monitor)
Your own site
<a href="https://agentmods.dev/skills/aeonfun/aeon/competitor-monitor"><img src="https://agentmods.dev/badge/skills/aeonfun/aeon/competitor-monitor/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for competitor-monitor

Your own site · 80×15
<a href="https://agentmods.dev/skills/aeonfun/aeon/competitor-monitor"><img src="https://agentmods.dev/badge/skills/aeonfun/aeon/competitor-monitor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 52 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,394 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00052 $0.03394
Opus 5 $0.00026 $0.01697
Sonnet 5 $0.00010 $0.00679
Haiku 4.5 $0.00005 $0.00339

Measured yesterday against content hash 0b4cb0f9817b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

competitor-monitor scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

skills/competitor-monitor/SKILL.md · 283 lines

How it starts

The opening of the file, as written. The whole thing — 283 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Today is ${today}.

${var} — the pages to watch, comma-separated.

  • empty → read the watch list from memory/competitors.md.
  • https://rival.com/pricing, https://rival.com → watch exactly these pages this run (a bare host gets https:// prepended). Watch specific pages, not just origins: /pricing, /changelog, /blog are where a competitor's moves actually show up.
  • add:<url> → append <url> to memory/competitors.md, confirm, and end (the shape the Telegram force-reply sends). No monitor runs.

What this does

Fetches each watched page, extracts the handful of signals a human would notice if they reopened the tab — the pricing numbers, the section headings, the call-to-action buttons, the nav/footer links, the <title> and meta description — snapshots them, and diffs today's snapshot against the previous run. It reports only the differences, ranked by how much they matter (a pricing change beats a reworded button), and keeps a durable log of every change it has ever seen.

The heavy lifting is in scripts/competitor-monitor.mjs, which returns machine-readable signals and a machine-computed diff, so you reason over facts instead of eyeballing two HTML dumps. Diffing signals, not raw HTML, is the whole point — raw HTML churns every deploy (build hashes, nonces, inlined timestamps) and would fire on every run. Signals only move when the site actually moved.

This reads what a page serves. A pure client-rendered SPA that ships an empty shell will look thin — the meta tags and any server-rendered copy still diff, but JS-injected content won't. Most marketing, pricing, blog, and changelog pages are server-rendered enough to track; say so if a target comes back near-empty rather than inventing signal.

Capability notes (read before editing this skill)

This skill is mode: read-only, and that is load-bearing (same contract as seo-audit):

  • The scraper is stdlib Node, not PythonBash(node:*) is in the read-only capability base; Bash(python3:*) is write-tier. Porting to Python forces mode: write.
  • No Write or Edit tool, and no shell output redirection. Read-only mode strips Write/Edit and the Bash permission layer blocks > file / >> file as defense-in-depth. So every file this skill produces is written by a Bash(node:*) command that opens the file itself — the snapshot/diff script takes --out FILE, and CHANGES.md is written by piping its content into a one-line node writer (both shown below). Do not use > — it will be refused mid-run. The read-only guard reverts writes to code/config paths but preserves memory/ and output/, which is exactly where this skill writes.
  • No secrets, no requires:. It only makes outbound HTTPS GETs.

Read the full file on GitHub · 283 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday Changed · +13 lines 0b4cb0f9817b
  2. 12d ago First seen · 270 lines · 52 tokens per session scan A ff2d1681a378

Subscribe to this mod's changes

competitor-monitor is a skill published in the GitHub repository aeonfun/aeon (723 stars, last pushed today), licensed MIT. It adds 52 tokens to every session and 3,394 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.