fenic: Instructions file for Claude Code

CLAUDE.md

fenic CLAUDE.md is an instructions file for Claude Code from typedef-ai/fenic. It costs 1,047 tokens per session, scanned A, original, Apache-2.0.

Project instructions for developing fenic, a Python framework for transforming AI and language-model data, including setup, dependencies, and tests.

In plain words
What is it for?
Use them when working on fenic to follow its setup process, synchronize Python or Rust dependencies, build Rust extensions, and run local or cloud tests.
Why use it?
They give coding agents the project’s background and the commands needed to prepare, test, and maintain the repository.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md; mentions Claude Code; mentions AGENTS.md.

This is typedef-ai/fenic's own configuration. It tells Claude Code how to work on fenic itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything fenic configures →

Reuse

Borrowing it

Nothing to install: this file belongs to typedef-ai/fenic. 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/typedef-ai/fenic/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/typedef-ai/fenic

Made for: Claude Code.

Wrote this? Show the measurements

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README.md
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<a href="https://agentmods.dev/instructions/typedef-ai/fenic/claude-md"><img src="https://agentmods.dev/badge/instructions/typedef-ai/fenic/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,047 This file is loaded in full into every session.
When invoked 1,047 The same file — it is already loaded in full.
Security scan A 0 findings. 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 5.1 $0.01047 $0.01047
Opus 5 $0.00524 $0.00524
Sonnet 5 $0.00209 $0.00209
Haiku 4.5 $0.00105 $0.00105

Measured 6d ago against content hash da648820827f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

fenic 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 6d 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 · 129 lines

How it starts

The opening of the file, as written. The whole thing — 129 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

@AGENTS.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository. The @AGENTS.md line above pulls in the cross-agent quick-reference for writing fenic pipelines (also read natively by Codex, Cursor, Gemini CLI, etc.); the rest of this file covers developing fenic itself. For deep authoring help, the fenic-mechanics skill auto-loads in Claude Code.

Project Overview

Fenic is a PySpark-inspired DataFrame framework specifically designed for AI and LLM applications. It provides semantic operators for LLM-powered data transformations, native support for unstructured data (markdown, transcripts, JSON), and efficient batch inference across multiple model providers (OpenAI, Anthropic, Google).

Development Commands

Setup and Dependencies

# Initial setup (installs dependencies and builds Rust extensions)
just setup

# Sync Python dependencies
just sync

# Build Rust extensions (required after Rust code changes)
just sync-rust

# Sync with cloud extras
just sync-cloud

Testing

# Run local tests (excludes cloud tests)
just test
# or
just test-local

# Run cloud-related tests
just test-cloud

# Run specific test file
uv run pytest tests/path/to/test_file.py

# Run specific test
uv run pytest tests/path/to/test_file.py::test_function_name

Linting and Formatting

# Ruff is configured for linting (Google-style docstrings)
# Auto-formats code examples in docstrings
uv run ruff check .
uv run ruff format .

Documentation

# Preview documentation locally
just preview-docs

Architecture Overview

Directory Structure

  • src/fenic/: Main Python source code
    • api/: Public API - Session, DataFrame, Functions, IO
    • core/: Core logic - logical plans, expressions, types, optimizer
    • _backends/: Execution backends (local using Polars, cloud using gRPC)
    • _inference/: LLM inference clients for different providers
  • rust/: Rust source for performance-critical operations (text chunking, markdown/JSON parsing)
  • tests/: Test suite (pytest-based)
  • examples/: Example applications demonstrating fenic usage

Read the full file on GitHub · 129 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. 6d ago First seen · 129 lines · 1,047 tokens per session scan A da648820827f

Subscribe to this mod's changes

fenic CLAUDE.md is an instructions file published in the GitHub repository typedef-ai/fenic (670 stars, last pushed 4d ago), licensed Apache-2.0. It adds 1,047 tokens to every session, about $0.0052 per session on Opus 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.

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