startup-v1-feasibility

startup-v1-feasibility is a skill for Claude Code from forjd/startup-ideation-skills. It costs 40 tokens per session (1,877 once invoked), scanned A, original, MIT.

A guide for deciding what to build first after a startup problem has been tested with real prospects. It narrows the idea to a small first version, or v1, designed to test the most important remaining assumption within two to four weeks.

In plain words
What is it for?
Use it to check whether an idea is ready to build, define a narrow first release, identify missing evidence, and plan a focused experiment-driven build.
Why use it?
It helps prevent scope creep and avoids building a large product before there is enough evidence that people need it.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the startup-ideation-skills plugin — 6 skills shipped together

Good fit Use it to check whether an idea is ready to build, define a narrow first release, identify missing evidence, and plan a focused experiment-driven build.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/forjd/startup-ideation-skills/startup-v1-feasibility
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.

Any agent
npx skills add forjd/startup-ideation-skills --skill startup-v1-feasibility
Clone the repo
git clone --depth 1 https://github.com/forjd/startup-ideation-skills

Made for: Claude Code.

Or install startup-ideation-skills, the plugin that ships this one along with the rest of its 6 skills.

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 startup-v1-feasibility

README.md
[![agentmods](https://agentmods.dev/badge/skills/forjd/startup-ideation-skills/startup-v1-feasibility/github.svg)](https://agentmods.dev/skills/forjd/startup-ideation-skills/startup-v1-feasibility)
Your own site
<a href="https://agentmods.dev/skills/forjd/startup-ideation-skills/startup-v1-feasibility"><img src="https://agentmods.dev/badge/skills/forjd/startup-ideation-skills/startup-v1-feasibility/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.

agentmods 80×15 button for startup-v1-feasibility

Your own site · 80×15
<a href="https://agentmods.dev/skills/forjd/startup-ideation-skills/startup-v1-feasibility"><img src="https://agentmods.dev/badge/skills/forjd/startup-ideation-skills/startup-v1-feasibility.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,877 The whole file, excluding the scripts and references it only reads on demand.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00040 $0.01877
Opus 5 $0.00020 $0.00938
Sonnet 5 $0.00008 $0.00375
Haiku 4.5 $0.00004 $0.00188

Measured 11d ago against content hash 0ca2b2626834, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

startup-v1-feasibility 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 11d 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.

skills/startup-v1-feasibility/SKILL.md · 263 lines

How it starts

The opening of the file, as written. The whole thing — 263 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Startup V1 Feasibility

When to use

Use when a captured, grilled, and validated startup problem has enough evidence to justify deciding what to build first.

This skill prevents v1 scope creep. The first version should test the riskiest useful assumption, not become a miniature version of the imagined company.

If the user has not run a validation test or cannot provide credible evidence from real prospects, do not produce a build plan by default. Return a Not build-ready verdict, list the missing evidence, and route them back to validation. Only produce a planning-only sketch when the user explicitly asks for a hypothetical plan and label it as unvalidated.

Core principle

A good v1 is small enough to build in 2–4 weeks and sharp enough that real user behaviour teaches something commercially useful.

Workflow

  1. Start from the evidence packet, problem ledger, grilling notes, and validation results.
  2. Check the v1 evidence gate before scoping:
    • Specific target user and buyer are known.
    • Current workaround and cost are grounded in real examples.
    • Founder advantage, recent enabling change, and first distribution route are plausible.
    • There is at least a rough expansion path beyond the first wedge.
    • At least one validation test produced behavioural signal, not compliments.
    • The strongest remaining assumption is one a v1 can test.
  3. If the gate fails, stop and return the missing evidence plus the next validation move.
  4. Identify the narrow wedge: the painful sliver where a first product can deliver value.
  5. Identify the riskiest assumption that building can test.
  6. Choose a v1 mode: manual concierge, Wizard-of-Oz, internal tool, workflow wrapper, integration, report, landing page plus manual fulfilment, narrow automation, or paid pilot.
  7. Define the smallest user journey that proves value.
  8. Cut scope until it is almost uncomfortable.
  9. List what is explicitly out of scope.
  10. Define success and kill criteria before implementation.
  11. Produce a 2–4 week build plan only if the evidence gate and scope are credible.

Read the full file on GitHub · 263 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. 11d ago First seen · 263 lines · 40 tokens per session scan A 0ca2b2626834

Subscribe to this mod's changes

startup-v1-feasibility is a skill published in the GitHub repository forjd/startup-ideation-skills (2 stars, last pushed 2mo ago), licensed MIT. It adds 40 tokens to every session and 1,877 once invoked, about $0.0002 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 2026-08-31.

Related

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