haytham

haytham is a command for coding agents from arslan70/haytham. It costs 10 tokens per session (9,715 once invoked), scanned A, original, MIT.

A four-phase workflow for testing a startup idea and producing a detailed software specification. It covers idea validation, MVP scope, technical design, and implementation requirements, with approval gates between phases.

In plain words
What is it for?
Use it to research an idea, define the smallest useful product, choose its technical approach, and generate an OpenSpec that guides development.
Why use it?
It brings market research, product decisions, architecture, and specifications into one ordered process. This helps founders decide whether to proceed before asking an implementation agent to build.

Command

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the haytham plugin — 7 skills, 7 commands, 12 agents, 2 hooks shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/arslan70/haytham/haytham
Clone the repo
git clone --depth 1 https://github.com/arslan70/haytham

Or install haytham, the plugin that ships this one along with the rest of its 7 skills, 7 commands, 12 agents, 2 hooks.

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.

agentmods badge for haytham

README.md
[![agentmods](https://agentmods.dev/badge/commands/arslan70/haytham/haytham.svg)](https://agentmods.dev/commands/arslan70/haytham/haytham)
Your own site
<a href="https://agentmods.dev/commands/arslan70/haytham/haytham"><img src="https://agentmods.dev/badge/commands/arslan70/haytham/haytham.svg" alt="Measured on agentmods" height="20"></a>
Per session 10 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 9,715 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00010 $0.09715
Opus 5 $0.00005 $0.04858
Sonnet 5 $0.00002 $0.01943
Haiku 4.5 $0.00001 $0.00971

Measured 5d ago against content hash 4bea541e9aa7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

haytham 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 5d 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.

commands/haytham.md · 759 lines

How it starts

The opening of the file, as written. The whole thing — 759 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Haytham: Startup Idea Validation & Specification

You are orchestrating a 4-phase startup validation workflow. Follow each phase in order. Do not skip phases. In normal mode, do not proceed to the next phase without user approval at the gate. In BATCH_MODE, auto-approve all gates and skip all interactive review steps.

IMPORTANT: Always read agent output from files, not from conversation history. Before each phase, verify previous phase output files exist by reading them.

Progress Tracking

After the Setup section completes, call TodoWrite once to register the full pipeline as todos. Use these exact items:

  1. Phase 1 — Idea validation (WHY)
  2. Phase 1 gate — founder approves verdict
  3. Phase 2 — MVP scope & capabilities (WHAT)
  4. Phase 2 gate — founder approves capabilities
  5. Phase 3 — Architecture (HOW)
  6. Phase 3 gate — founder approves design
  7. Phase 4 — OpenSpec generation
  8. Final review

Mark the active item in_progress when starting the phase and completed when its output files are written and the digest is shown. Only one item in_progress at a time. If a gate triggers a re-run of the preceding phase, set that phase back to in_progress.

Upstream Dependencies

Phase Agent Reads From
1 idea-analyst .haytham/project.yaml (user input)
1 market-researcher phase-1-why/idea-analysis.md, phase-1-why/concept-anchor.json
1 competitor-researcher phase-1-why/idea-analysis.md, phase-1-why/concept-anchor.json
1 research-briefer phase-1-why/idea-analysis.md, phase-1-why/market-research.md, phase-1-why/competitor-research.md
1 report-synthesizer phase-1-why/research-brief.md, phase-1-why/concept-anchor.json, phase-1-why/competitor-research.md, phase-1-why/founder-corrections.json (if exists), references/benchmarks.md
2 mvp-scoper phase-1-why/validation-report.md, phase-1-why/idea-analysis.md, phase-1-why/concept-anchor.json
2 capability-modeler phase-2-what/mvp-scope.md, phase-1-why/idea-analysis.md, phase-1-why/concept-anchor.json
2 capability-checker phase-2-what/mvp-scope.md, phase-2-what/capabilities.json, phase-1-why/concept-anchor.json
3 architect phase-2-what/capabilities.json, phase-2-what/system-traits.json, phase-2-what/mvp-scope.md
4 spec-generator phase-2-what/capabilities.json, phase-2-what/mvp-scope.md, phase-2-what/system-traits.json, phase-3-how/architecture-decisions.json, phase-3-how/build-buy.json, phase-1-why/concept-anchor.json
5 build (command) phase-4-specs/openspec/, phase-3-how/research-directives.json

Read the full file on GitHub · 759 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. 5d ago First seen · 759 lines · 10 tokens per session scan A 4bea541e9aa7

Subscribe to this mod's changes

haytham is a command published in the GitHub repository arslan70/haytham (13 stars, last pushed 1mo ago), licensed MIT. It adds 10 tokens to every session and 9,715 once invoked, about $0.0001 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.