What is bot-signal AGENTS.md?

Project instructions for bot-signal, a TypeScript library that detects automated browsers, bots, and HTTP clients using browser and server checks.

Adding or maintaining browser-side, behavioural, WebGPU, and Node.js detection APIs, user-agent parsing, confidence results, and related tests.

They clarify the library's detection layers and warn that automation and framework identification are probabilistic rather than certain.

How okasi/bot-signal configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to okasi/bot-signal. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/okasi/bot-signal/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/okasi/bot-signal

Made for: Codex, OpenCode.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/okasi/bot-signal/agents-md/github.svg)](https://agentmods.dev/instructions/okasi/bot-signal/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/okasi/bot-signal/agents-md"><img src="https://agentmods.dev/badge/instructions/okasi/bot-signal/agents-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/okasi/bot-signal/agents-md"><img src="https://agentmods.dev/badge/instructions/okasi/bot-signal/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 2,817 This file is loaded in full into every session.

When invoked 2,817 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.02817	$0.02817
Opus 5.5	$0.01127	$0.01127
Sonnet 5.5	$0.00563	$0.00563
Haiku 4.5	$0.00282	$0.00282

Measured 1mo ago against content hash bcfe9397bc48, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

bot-signal AGENTS.md 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 1mo ago.

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.

AGENTS.md · 223 lines

How it starts

The opening of the file, as written. The whole thing — 223 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Guidance for AI agents and contributors working on the bot-signal package (npm name: bot-signal, GitHub: okasi/bot-signal). It exports isHuman() etc. as the simple entry points plus full detection APIs.

Project overview

TypeScript npm library with three detection layers:

Layer	Entry point	Location
Instant (browser)	`detectInstantClient`	`src/detectInstantClient.ts`, `src/checks.ts`, `src/asyncChecks.ts`, `src/webgpu.ts`
Behavioral (browser)	`createBehavioralClientDetector`	`src/behavioral/`
Server (Node)	`detectServerClientAsync`	`src/server/`

src/automation.ts contains the shared best-effort attribution result types. Instant and server results expose automation (kind, confidence, evidence, and alternatives); stealth framework names are probabilistic, not definitive. src/userAgent.ts contains shared scripting-client and conservative bot/HTTP-client/automation User-Agent token parsing.

Entry points: src/index.ts (full API), src/browser.ts (browser-only), src/server.ts (server-only). The package.json exports map routes the root import to the browser build under the browser condition so browser bundlers never see node:fs. src/version.ts provides VERSION. Build output: dist/ (tsup — ESM + CJS + IIFE browser.global.js for CDNs).

Repository layout

src/
  index.ts                    # root entry (full API)
  browser.ts                  # browser entry (instant + behavioral)
  server.ts                   # server entry (server detection only)
  automation.ts               # shared automation attribution types/helper
  userAgent.ts                # shared scripting/bot/HTTP-client/automation UA parser
  detectInstantClient.ts      # instant detection entry
  checks.ts                   # high-value browser checks
  asyncChecks.ts              # CDP, permissions, UA-CH, media devices, worker WebDriver/OS/WebGL checks
  webgpu.ts                   # shader-f16 + isChromiumBrowser
  behavioral/
    analysis.ts               # mouse/touch/CDP-input/scroll/typing heuristics
    scoring.ts                # weighted score aggregation
    index.ts                  # detector (DOM event listener lifecycle)
    types.ts
  server/
    geoip.ts                  # doc999tor-fast-geoip wrapper
    ipLists.ts                # parseIp + interval matching (IPv4/IPv6, binary search)
    enrich.ts                 # auto-fill context from clientIp
    analysis.ts               # request contradictions + trusted crawler-verification verdict
    scoring.ts                # detectServerClient(Async)
    tls.ts                    # JA3 blocklist + UA mismatch
    timezone.ts               # TZ offset + accept-language checks
    types.ts
data/                         # bundled blocklists (shipped in npm package)
docs/                         # GitHub Pages demo source (index.html + app.js)
scripts/build-site.ts         # builds .pages/ with dist/browser.js + stamped asset URLs
scripts/update-ip-data.ts     # fetches and writes data/*.csv
test/                         # vitest unit + patchright and playwright browser tests
  fixtures/harness.html         # DOM fixtures for browser tests
  helpers/                      # test server + patchright harness
  patchright/                   # real Chromium tests via patchright
  playwright/                   # actual Playwright, headed/headless, page-owned detection
.github/workflows/
  ci.yml                      # typecheck + unit + both browser suites + build (Node 22+)
  pages.yml                   # build .pages/ and deploy via GitHub Pages Actions
  publish.yml                 # publish to npm on v* tags
  update-ip-data.yml          # weekly blocklist refresh

Read the full file on GitHub · 223 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.

1mo ago Changed · +5 lines · +176 tokens per session bcfe9397bc48
2mo ago First seen · 218 lines · 2,641 tokens per session scan A d92d06076ce4

Subscribe to this mod's changes

bot-signal AGENTS.md is an instructions file published in the GitHub repository okasi/bot-signal (545 stars, last pushed 4d ago), licensed MIT. It adds 2,817 tokens to every session, about $0.0113 per session on Opus 5.5. 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.

anti-bot automation-detection behavioral-analysis bot-detection browser-fingerprinting cybersecurity

bot-signal AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
bot-signal AGENTS.mdokasi/bot-signal	Instructions file	545	4d ago	MIT	A	2,817	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
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vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

bot-signal: Instructions file for Codex