Borrowing it
Nothing to install: this file belongs to healthchainai/HealthChain. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/healthchainai/HealthChain/main/CLAUDE.mdgit clone --depth 1 https://github.com/healthchainai/HealthChainWrote 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.
[](https://agentmods.dev/instructions/healthchainai/healthchain/claude-md)<a href="https://agentmods.dev/instructions/healthchainai/healthchain/claude-md"><img src="https://agentmods.dev/badge/instructions/healthchainai/healthchain/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.
<a href="https://agentmods.dev/instructions/healthchainai/healthchain/claude-md"><img src="https://agentmods.dev/badge/instructions/healthchainai/healthchain/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.01852 | $0.01852 |
| Opus 5.5 | $0.00741 | $0.00741 |
| Sonnet 5.5 | $0.00370 | $0.00370 |
| Haiku 4.5 | $0.00185 | $0.00185 |
Grade A, and why
HealthChain 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 24d 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.
How it starts
The opening of the file, as written. The whole thing — 126 lines — stays where its author put it; the contents beside it link to each section on GitHub.
HealthChain - Claude Code Context
Purpose: This file guides AI assistants and developers working on HealthChain. It encodes coding standards, constraints, and workflows to keep architecture and domain judgment in human hands. It's a working document that will be updated as the project evolves.
0. Project Overview
HealthChain is an open-source Python library for live FHIR connectivity and validated FHIR tooling. It connects Python pipelines and applications to FHIR APIs, helps them produce coded, validated FHIR, and delivers results through healthcare and agent interfaces.
Key Problem: Healthcare data applications are often tied to one site's schemas and connection logic, while structural and coding errors may surface only after FHIR reaches a downstream system. HealthChain provides a consistent FHIR boundary around user-owned logic.
Target Users (in priority order):
- Research software and healthcare data teams building reusable tools, studies, and data services
- Healthcare integration engineers working across research organizations, hospitals, payers, and health technology companies
- AI, agent, and general Python developers building healthcare and personal health applications
For more background, read README.md and docs/index.md.
1. Non-Negotiable Golden Rules
| # | AI may do | AI must NOT do |
|---|---|---|
| G-0 | When unsure about implementation details or requirements, ask developer for clarification before making changes. | ❌ Write changes or use tools when you are not sure about something project specific, or if you don't have context for a particular feature/decision. |
| G-1 | Generate code inside healthchain/ or explicitly pointed files. |
❌ Modify or create test files without explicit approval. |
| G-2 | For changes >200 LOC or >3 files, propose a plan and wait for confirmation. | ❌ Refactor large modules without human guidance. |
| G-3 | Follow lint/style configs (pyproject.toml, .ruff.toml). Use ruff for formatting. |
❌ Reformat code to any other style. |
| G-4 | Stay within the current task context. Inform the dev if it'd be better to start afresh. | ❌ Continue work from a prior prompt after "new task" – start a fresh session. |
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.
- 24d ago Changed · -64 lines · -439 tokens per session b47b046ae75b
- 2mo ago First seen · 190 lines · 2,291 tokens per session scan A 1464821edd72
HealthChain CLAUDE.md is an instructions file published in the GitHub repository healthchainai/HealthChain (231 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,852 tokens to every session, about $0.0074 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.
HealthChain CLAUDE.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| HealthChain CLAUDE.mdhealthchainai/HealthChain | Instructions file | 231 | yesterday | Apache-2.0 | A | 1,852 | Claude Code |
| 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 |
| 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 |