Fpf
First Principles Framework (FPF) for structured reasoning using workflow command pattern. Implements ADI (Abduction-Deduction-Induction) cycle via propose-hypotheses workflow with fpf-agent for hypothesis generation, logical verification, empirical validation, and auditable decision-making. Includes utility commands for status, query, decay, actualize, and reset.
- Type
- Plugin
- Repository
- NeoLabHQ/context-engineering-kit
- GitHub stars
- 1.7k
- License
- GPL-3.0
- Repo last updated
- Aug 26, 2026
- Source file
- plugins/fpf/.claude-plugin/plugin.json
- Version
- 3.0.0
- Author
- Vlad Goncharov
What Fpf is
Fpf is a plugin published in the NeoLabHQ/context-engineering-kit repository on GitHub, which has about 1.7k stars. The repository describes itself as: “Hand-crafted Claude Code Skills focused on improving agent results quality. Compatible with OpenCode, Cursor, Antigravity, Gemini CLI, and others. Includes CodeRabbit open-source alternative.”
A plugin is a package that bundles skills, slash commands, subagents, hooks, and MCP connectors so they install together. Plugins are plain files with a manifest at .claude-plugin/plugin.json, and they work in both Claude Code and Claude Cowork.
Installing Fpf adds everything it ships in one step. Connectors inside a plugin still need to be connected separately, and hooks and subagents only run in Cowork and Claude Code, not in regular chat.
How to install Fpf
Claude Code
- Add the repository as a plugin marketplace: claude plugin marketplace add NeoLabHQ/context-engineering-kit
- Install the plugin: claude plugin install fpf@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json.
- Restart the session if the new skills or commands don't appear straight away.
Claude Cowork
- Open Customize → Plugins and choose Add marketplace.
- Enter NeoLabHQ/context-engineering-kit (the owner/repo shorthand works for GitHub).
- Find Fpf in the list, click Install, then connect any connectors it needs from its Connectors tab.
New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.
Inside the source file
An excerpt from plugins/fpf/.claude-plugin/plugin.json, shared under the repository's GPL-3.0 license. Read the full file on GitHub.
Structured reasoning plugin that makes AI decision-making transparent and auditable through hypothesis generation, logical verification, and evidence-based validation.
Focused on:
- Transparent reasoning - All decisions documented with full audit trails
- Hypothesis-driven analysis - Generate competing alternatives before evaluating
- Evidence-based validation - Computed reliability scores, not estimates
- Human-in-the-loop - AI generates options; humans decide (Transformer Mandate)
Plugin Target
- Make AI reasoning auditable - full trail from hypothesis to decision
- Prevent premature conclusions - enforce systematic evaluation of alternatives
- Build project knowledge over time - decisions become reusable knowledge
- Enable informed decision-making - trust scores based on evidence quality
Overview
The FPF plugin implements structured reasoning using the First Principles Framework methodology developed by Anatoly Levenchuk a methodology for rigorous, auditable reasoning. The killer feature is turning the black box of AI reasoning into a transparent, evidence-backed audit trail.
The core cycle follows three modes of inference:
- Abduction — Generate competing hypotheses (don't anchor on the first idea).
- Deduction — Verify logic and constraints (does the idea make sense?).
- Induction — Gather evidence through tests or research (does the idea work in reality?).
Then, audit for bias, decide, and document the rationale in a durable record.
The framework addresses a fundamental challenge in AI-assisted development: making decision-making processes transparent and auditable. Rather than having AI jump to solutions, FPF enforces generating competing hypotheses, checking them logically, testing against evidence, then letting developers choose the path forward.
> Warning: This plugin loads the core FPF specification into context, which is large (~600k tokens). As a result it loaded into a subagent with Sonnet[1m] model. But such agent can consume your token limit quickly.
Implementation based on quint-code by m0n0x41d.
Quick Start
# Install the plugin
/plugin install fpf@NeoLabHQ/context-engineering-kit
# Start a decision process
/propose-hypotheses What caching strategy should we use?
# Commad will perform majority of orcestration and launch subagents to perform the work.
# Additionaly you will be asked to add your own hypotheses and review the results.Workflow Diagram
┌─────────────────────────────────────────────────────────────────┐
│ 1. Initialize Context │
│ /propose-hypotheses <problem> │
│ (create .fpf/ directory structure) │
└────────────────────────┬────────────────────────────────────────┘
│
│ problem context captured
▼
┌─────────────────────────────────────────────────────────────────┐
│ 2. Abduction: Generate Hypotheses │ ◀── add your own ───┐
│ (create L0 hypothesis files) │ │
└────────────────────────┬────────────────────────────────────────┘ │
│ │
│ 3-5 competing hypotheses │
▼ │
┌─────────────────────────────────────────────────────────────────┐ │
│ 3. User Input │ │
│ (present summary, allow additions) │─────────────────────┘
…Commands Overview
/propose-hypotheses - Decision Cycle
Execute the complete FPF cycle from hypothesis generation through evidence validation to decision.
- Purpose - Make architectural decisions with full audit trail
- Output - .fpf/decisions/DRR- - .md with winner and rationale
/propose-hypotheses [problem or decision to make]Arguments
Natural language description of the decision or problem. Examples: "What caching strategy should we use?" or "How should we deploy our application?"
How It Works - ADI Cycle
The workflow follows three inference modes:
- Initialize Context - Creates .fpf/ directory structure and captures problem constraints
- Abduction: Generate Hypotheses - FPF agent generates 3-5 generate plausible, diverse, and competing hypotheses in L0 folder. How it works:
- You pose a problem or question
- The AI (as Abductor persona) generates 3-5 candidate explanations or solutions
- Each hypothesis is stored in L0/ (unverified observations)
Before you install
- Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
- Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
- Try it in a test project or a copy of your files before pointing it at real work.
- Pin the version you tested, and review changes before updating.
- Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.
FAQ
What is Fpf?
Fpf is a plugin for Claude Code and Claude Cowork from the NeoLabHQ/context-engineering-kit repository on GitHub. First Principles Framework (FPF) for structured reasoning using workflow command pattern. Implements ADI (Abduction-Deduction-Induction) cycle via propose-hypotheses workflow with fpf-agent for hypothesis generation, logical verification, empirical validation, and auditable decision-making. Includes utility commands for status, query, decay, actualize, and reset.
How do I install Fpf in Claude Code?
Add the repository as a plugin marketplace: claude plugin marketplace add NeoLabHQ/context-engineering-kit Install the plugin: claude plugin install fpf@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json. Restart the session if the new skills or commands don't appear straight away.
Can I use Fpf in Claude Cowork?
Open Customize → Plugins and choose Add marketplace. Enter NeoLabHQ/context-engineering-kit (the owner/repo shorthand works for GitHub). Find Fpf in the list, click Install, then connect any connectors it needs from its Connectors tab.
Is Fpf safe to install?
It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.
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