What is FirstData CLAUDE.md?

Repository instructions for FirstData, a data-only collection describing reliable public data sources for AI agents. It explains the project structure, dependency setup, and validation commands.

Adding or changing descriptions of government, international, academic, and other open-data sources, then checking the files with the project's validation tools.

They help contributors edit source metadata correctly and catch invalid JSON, duplicate IDs, or inconsistent domain names before submission.

How MLT-OSS/FirstData configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to MLT-OSS/FirstData. 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/MLT-OSS/FirstData/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/MLT-OSS/FirstData

Made for: Claude Code.

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/mlt-oss/firstdata/claude-md/github.svg)](https://agentmods.dev/instructions/mlt-oss/firstdata/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/mlt-oss/firstdata/claude-md"><img src="https://agentmods.dev/badge/instructions/mlt-oss/firstdata/claude-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/mlt-oss/firstdata/claude-md"><img src="https://agentmods.dev/badge/instructions/mlt-oss/firstdata/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 1,912 This file is loaded in full into every session.

When invoked 1,912 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	$0.01912	$0.01912
Opus 5.5	$0.00765	$0.00765
Sonnet 5.5	$0.00382	$0.00382
Haiku 4.5	$0.00191	$0.00191

Measured 2mo ago against content hash 77a94b07893a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

FirstData CLAUDE.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 2mo 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.

CLAUDE.md · 174 lines

How it starts

The opening of the file, as written. The whole thing — 174 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

FirstData is the External Facts Context Layer for AI Agents — a structured, authoritative collection of global open data sources. It is a pure data repository — no application code, no runtime logic.

Your job here is to create or edit JSON metadata files that describe real-world data sources (government databases, international organizations, academic datasets, etc.).

The project exposes a hosted MCP Server at https://firstdata.deepminer.com.cn/mcp.

Validation

Dependencies are managed with uv. Run the following before submitting:

# Install dependencies (first time only)
uv sync

# Run all validation checks
make check

# Or run checks individually:
make validate       # Validate JSON schema compliance
make check-ids      # Check for duplicate IDs
make check-domains  # Check domain naming consistency

A GitHub Action runs these checks automatically on every PR. PRs that fail validation cannot be merged.

Repository Structure

firstdata/
├── schemas/datasource-schema.json   # JSON Schema v2.0.0 (the source of truth for data format)
├── sources/                         # Individual data source JSON files, organized by category
│   ├── china/                       # Chinese government & institutions
│   ├── international/               # International organizations (by domain)
│   ├── countries/                   # National official sources (by continent/country)
│   ├── academic/                    # Academic research databases (by discipline)
│   └── sectors/                     # Industry sources (by ISIC Rev.4 code)
└── indexes/                         # Auto-generated aggregated indexes (do not edit manually)
    ├── all-sources.json
    ├── by-authority.json
    ├── by-domain.json
    ├── by-region.json
    └── statistics.json

The JSON Schema

Every file under firstdata/sources/ must conform to firstdata/schemas/datasource-schema.json.

Read the full file on GitHub · 174 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.

2mo ago First seen · 174 lines · 1,912 tokens per session scan A 77a94b07893a

Subscribe to this mod's changes

FirstData CLAUDE.md is an instructions file published in the GitHub repository MLT-OSS/FirstData (186 stars, last pushed 1mo ago), licensed MIT. It adds 1,912 tokens to every session, about $0.0076 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.

Data and AI ai awesome-list data-sources datasets fact-checking mcp

FirstData CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
FirstData CLAUDE.mdMLT-OSS/FirstData	Instructions file	186	1mo ago	MIT	A	1,912	Claude Code
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langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
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

FirstData: Instructions file for Claude Code