crossfin AGENTS.md

crossfin AGENTS.md is an instructions file for Codex, OpenCode from bubilife1202/crossfin. It costs 1,327 tokens per session, scanned A, original, MIT.

A project instruction file describing CrossFin, a cross-border crypto routing engine for AI agents, its architecture, key files, and API address.

In plain words
What is it for?
Understanding the CrossFin codebase, locating important files, and working with its API, exchange-routing logic, MCP server, web demo, and documentation.
Why use it?
It gives coding agents the project context they need before changing code, reducing guesswork about how the repository is organized and what its main components do.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/bubilife1202/crossfin/agents-md
Clone the repo
git clone --depth 1 https://github.com/bubilife1202/crossfin

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.

agentmods badge for crossfin AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/bubilife1202/crossfin/agents-md.svg)](https://agentmods.dev/instructions/bubilife1202/crossfin/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/bubilife1202/crossfin/agents-md"><img src="https://agentmods.dev/badge/instructions/bubilife1202/crossfin/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,327 This file is loaded in full into every session.
When invoked 1,327 The same file — it is already loaded in full.
Security scan A 1 finding. Scan, not verified.
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 $0.01327 $0.01327
Opus 5 $0.00664 $0.00664
Sonnet 5 $0.00265 $0.00265
Haiku 4.5 $0.00133 $0.00133

Measured 3d ago against content hash 84ee18a9af23, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

crossfin AGENTS.md scanned grade A with 1 finding 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 3d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl https://crossfin.dev/api/health
AGENTS.md · 145 lines

How it starts

The opening of the file, as written. The whole thing — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md — CrossFin

What is CrossFin?

Cross-border crypto routing engine for AI agents. Routes capital across 14 Korean and global exchanges with x402 USDC micropayments on Base.

Architecture

apps/
  api/          Hono on Cloudflare Workers — main API (x402, registry, routing, market data)
  mcp-server/   MCP server (npm: crossfin-mcp) — 16 tools for Claude, Cursor, etc.
  web/          React demo — local ledger UI
  live/         Live demo site (live.crossfin.dev)
  docs/         VitePress documentation (docs.crossfin.dev)
  demo-video/   Remotion video generator

Key Files

  • apps/api/src/index.ts — All API routes (~11500 lines)
  • apps/api/src/constants.ts — Exchange fees, bridge coins, routing config
  • apps/api/src/types.ts — Type definitions and utility functions
  • apps/api/src/lib/fetchers.ts — Exchange data fetchers
  • apps/api/src/lib/engine.ts — Routing engine logic
  • apps/api/src/catalog.ts — Service catalog metadata (from catalog/crossfin-catalog.json)
  • apps/mcp-server/src/index.ts — MCP server with 16 tools
  • apps/mcp-server/src/ledgerStore.ts — Local JSON ledger for agent wallets

API Base URL

Production: https://crossfin.dev

Endpoints Overview

  • Free: health, exchange list, fees, pairs, status, arbitrage demo, routing graph, registry, ACP quote
  • Paid (x402 USDC on Base): route finding ($0.10), kimchi premium ($0.05), orderbooks ($0.02), Korean stocks ($0.03-$0.05), bundles ($0.10-$0.20)

Discovery Endpoints

  • /.well-known/crossfin.json — CrossFin agent discovery
  • /.well-known/x402.json — x402 payment discovery
  • /.well-known/agent.json — Google A2A Agent Card
  • /.well-known/ai-plugin.json — OpenAI plugin manifest
  • /llms.txt — LLM-readable site map
  • /api/openapi.json — OpenAPI 3.1 spec
  • /api/docs/guide — Structured agent onboarding guide

Exchanges

Korea: Bithumb, Upbit, Coinone, GoPax Regional: bitFlyer (JPY), WazirX (INR), bitbank (JPY), Indodax (IDR), Bitkub (THB) Global: Binance, OKX, Bybit, KuCoin, Coinbase Bridge coins: BTC, ETH, XRP, SOL, DOGE, ADA, DOT, LINK, AVAX, TRX, KAIA, SUI, APT

Read the full file on GitHub · 145 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. 3d ago First seen · 145 lines · 1,327 tokens per session scan A 84ee18a9af23

Subscribe to this mod's changes

crossfin AGENTS.md is an instructions file published in the GitHub repository bubilife1202/crossfin (1 stars, last pushed 6mo ago), licensed MIT. It adds 1,327 tokens to every session, about $0.0066 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.