What is instructor CLAUDE.md?

A development guide for Instructor, a Python project, covering setup, testing, type checking, code style, coverage, and MkDocs documentation.

Use it when installing dependencies, running or filtering tests, checking types, linting, formatting, measuring coverage, or building the documentation.

It gathers the project's expected commands and setup steps in one place, reducing inconsistent environments and incomplete checks.

How 567-labs/instructor configures Claude Code

About the project

Instructor is a library that helps applications obtain structured, validated data from language models using Pydantic models. It is for developers building LLM features such as data extraction across different model providers, and the catalogue entries add usage rules and instructions.

567-labs/instructor · 14,098 stars · on GitHub · python.useinstructor.com

Reuse

Borrowing it

Nothing to install: this file belongs to 567-labs/instructor. 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/567-labs/instructor/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/567-labs/instructor

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/567-labs/instructor/claude-md/github.svg)](https://agentmods.dev/instructions/567-labs/instructor/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/567-labs/instructor/claude-md"><img src="https://agentmods.dev/badge/instructions/567-labs/instructor/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/567-labs/instructor/claude-md"><img src="https://agentmods.dev/badge/instructions/567-labs/instructor/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 3,148 This file is loaded in full into every session.

When invoked 3,148 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	$0.03148	$0.03148
Opus 5.5	$0.01259	$0.01259
Sonnet 5.5	$0.00630	$0.00630
Haiku 4.5	$0.00315	$0.00315

Measured 2mo ago against content hash 374feaaccf38, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

instructor 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 · 304 lines

How it starts

The opening of the file, as written. The whole thing — 304 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.

Instructor Development Guide

Commands

Install deps: uv pip install -e ".[dev,anthropic]" or poetry install --with dev,anthropic
Run tests: uv run pytest tests/ -n auto
Run specific test: uv run pytest tests/path_to_test.py::test_name
Skip LLM tests: uv run pytest tests/ -k 'not llm and not openai'
Type check: uv run ty check
Lint: uv run ruff check instructor examples tests
Format: uv run ruff format instructor examples tests
Generate coverage: uv run coverage run -m pytest tests/ -k "not docs" then uv run coverage report
Build documentation: uv run mkdocs serve (for local preview) or ./build_mkdocs.sh (for production)
Waiting: use sleep <seconds> for explicit pauses (e.g., CI waits) or to let external processes finish

Installation & Setup

Fork the repository and clone your fork
Install UV: pip install uv
Create virtual environment: uv venv
Install dependencies: uv pip install -e ".[dev]"
Install pre-commit: uv run pre-commit install
Run tests to verify: uv run pytest tests/ -k "not openai"

Code Style Guidelines

Typing: Use strict typing with annotations for all functions and variables
Imports: Standard lib → third-party → local imports
Formatting: Follow Black's formatting conventions (enforced by Ruff)
Models: Define structured outputs as Pydantic BaseModel subclasses
Naming: snake_case for functions/variables, PascalCase for classes
Error Handling: Use custom exceptions from exceptions.py, validate with Pydantic
Comments: Docstrings for public functions, inline comments for complex logic

Conventional Commits

Format: type(scope): description
Types: feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert
Examples:
- feat(anthropic): add support for Claude 3.5
- fix(openai): correct response parsing for streaming
- docs(README): update installation instructions
- test(gemini): add validation tests for JSON mode

Read the full file on GitHub · 304 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 · 304 lines · 3,148 tokens per session scan A 374feaaccf38

Subscribe to this mod's changes

instructor CLAUDE.md is an instructions file published in the GitHub repository 567-labs/instructor (14,098 stars, last pushed yesterday), licensed MIT. It adds 3,148 tokens to every session, about $0.0126 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.

Python openai openai-function-calli openai-functions pydantic-v2 validation

instructor CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
instructor CLAUDE.md567-labs/instructor	Instructions file	14k	yesterday	MIT	A	3,148	Claude Code
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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

instructor: Instructions file for Claude Code