Table Fit
asgeirtj/system_prompts_leaks
Keep a Markdown table readable in a narrow terminal of about 100 display columns - a wide table or one carrying prose in its cells wraps into unreadable ragged rows.
Run an honest market-fit and viability audit of any project or idea and produce a decision doc, not code.
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install tamdogood/builder-essential-skills validate-market --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/validate-market .claude/skills/validate-market && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .claude/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-marketType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install tamdogood/builder-essential-skills validate-market --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/validate-market .agents/skills/validate-market && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .agents/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install tamdogood/builder-essential-skills validate-market --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/validate-market .cursor/skills/validate-market && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .cursor/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/tamdogood/builder-essential-skills.git --path skills/validate-market--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install tamdogood/builder-essential-skills validate-market --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/validate-market .gemini/skills/validate-market && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .gemini/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install tamdogood/builder-essential-skills validate-marketInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/validate-market .github/skills/validate-market && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .github/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add tamdogood/builder-essential-skills --skill validate-market -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install tamdogood/builder-essential-skills validate-market --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/tamdogood/builder-essential-skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/validate-market .opencode/skills/validate-market && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "validate-market" agent skill from https://github.com/tamdogood/builder-essential-skills/tree/main/skills/validate-market into .opencode/skills/validate-market/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "validate-market", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
validate-marketRun an honest market-fit and viability audit of any project or idea and produce a decision doc, not code.
Validate Market is an agent skill from tamdogood/builder-essential-skills. Run an honest market-fit and viability audit of any project or idea and produce a decision doc, not code. Use when someone asks "is this viable as a business", "audit the market fit", "make the case and compare to competitors", "should I apply to YC or bootstrap", or wants to validate a project, product, or market before investing more time. Gathers verifiable traction data first, researches the competitive field, gets an independent cold read, writes a doc with pre-committed pass/middle/kill criteria and a…
Its SKILL.md is about 2.8k tokens, which your agent loads only when the skill is triggered. The skill folder holds 1 other file (for example `README.md`). Compatibility notes: claude-code
The repository describes itself as: A repository for skills that are essential to my daily work. The licence is MIT.
7 steps, taken from the step headings in SKILL.md.
Read from SKILL.md and the folder at commit 1be9984. It shows what the files ask for, not the result of running them.
Pre-approves these tools, so the agent can use them without asking each time:
ReadWriteEditGrepGlobBashWebSearchWebFetchAgentAskUserQuestionFrom allowed-tools in the SKILL.md frontmatter.
Shell commands in SKILL.md call:
ghcodexFrom the folder's file list and the shell code blocks in SKILL.md.
No URLs in SKILL.md. Its commands use gh, which can reach the network depending on how they are called.
From URLs in SKILL.md, links to its own repository left out.
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
claude-code
From compatibility in the SKILL.md frontmatter.
Validate Market loads about 2.8k tokens when it runs. Until then it costs about 151 tokens; SKILL.md has 1,556 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
The automated check noted patterns worth knowing about, such as sudo or a known installer.
allowed-tools: Read, Write, Edit, Grep, Glob, Bash, WebSearch, WebFetch, Agent, AskUserQuestionAutomated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
The full file from tamdogood/builder-essential-skills at commit 1be9984, republished under its MIT licence (© tamdogood). 1,556 words, ~2,792 tokens.
.claude/skills/validate-market/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.You are running a validation audit. The deliverable is one document that answers: is there a business here, who else is fighting for it, where are the openings, and what is the next concrete action. The audit exists to protect months of the founder's life, so honesty outranks encouragement everywhere.
Hard gate: no implementation. No code, no scaffolding, no renames, no site changes.
The only output is the doc (plus its adversarial review). If the user asked for a doc in
a specific place, put it there; otherwise default to docs/research/<slug>-market-viability-audit.md
in a repo, or ./<slug>-market-viability-audit.md outside one.
Collect verifiable numbers before writing a single judgment. Do not skip this; it is what separates an audit from a vibe.
gh repo view <repo> --json stargazerCount,forkCount,createdAt,isPrivate).curl the landing page, any public directory or
stats API). Distinguish "deployed" from "used".Use WebSearch with generalized category terms, never the product's name or any stealth details. Run at least these four searches and read the top results:
<category> protocol landscape <year>").<category> startups <year> funding").<big platform> <category> features <year>").Synthesize three things explicitly:
If WebSearch is unavailable, say so in the doc and proceed on in-distribution knowledge, clearly labeled as such.
Write 3 to 5 premises the whole recommendation rests on. Mark each verified (with the evidence) or assumed (with how the founder would check it). Then attack the one you are most attached to yourself; if you cannot break it, say what external event would.
Get a second opinion that has not seen your reasoning:
codex is on PATH: assemble a structured context block (product, stage and demand
evidence, founder's stated problem, landscape summary, premises) into a temp file and
run codex exec read-only against it with these asks: (1) steelman the strongest
version, (2) quote the one detail that reveals what to actually build, (3) name one
premise that is wrong and the evidence that would prove it, (4) a 48-hour plan with
channels, metrics, and kill criteria.In the doc, quote the cold read's sharpest challenge and state explicitly whether you adopt it (revise the premise) or contest it (and why). Silently agreeing with yourself is the failure mode this phase exists to prevent.
Structure (adapt names, keep the order; verdict first, evidence before judgment):
These are the holes adversarial review reliably finds. Close them before review:
End with, in the final message: the verdict in two sentences, the doc's location, the three-band decision rule, and the week-1 assignment. If the founder profile fits (real problem, domain expertise, agency), say so plainly and point at the relevant next step (accelerator application, design-partner outreach), but only when the evidence in the doc supports it. No congratulations for work the market has not yet validated.
© tamdogood, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
SKILL.md and 1 other file in skills/validate-market of tamdogood/builder-essential-skills.
Open the folder on GitHubat commit 1be9984
Validate Market next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Validate Market this skilltamdogood/builder-essential-skills | 221 | — | ~2.8k | Automated safety check: Notes | MIT | |
| Table Fitasgeirtj/system_prompts_leaks | 69k | — | ~772 | Automated safety check: Pass | CC0-1.0 | |
| Furniture Fit Checkpascalorg/editor | 25k | — | ~5.1k | Automated safety check: Pass | MIT | |
| Fitness Programrevfactory/harness-100 | 1.3k | — | ~1.8k | Automated safety check: Pass | Apache-2.0 | |
| Fit Scoreraaron-he-zhu/aaron-marketing-skills | 2.9k | — | ~4.2k | Automated safety check: Pass | Apache-2.0 | |
| Business Name Fitalirezarezvani/claude-skills | 28k | — | ~2.8k | Automated safety check: Pass | MIT |
asgeirtj/system_prompts_leaks
Keep a Markdown table readable in a narrow terminal of about 100 display columns - a wide table or one carrying prose in its cells wraps into unreadable ragged rows.
pascalorg/editor
Checks whether a sofa, table, bed or appliance fits in a measured Pascal room and reports only what the evidence supports, or asks for the missing measurements.
revfactory/harness-100
A full pipeline where an agent team collaborates to generate everything from goal-based fitness program design to progress tracking templates.
aaron-he-zhu/aaron-marketing-skills
A skill your agent uses when the user asks to "score this influencer", "rank these creators for our campaign", or "tell me which influencer is the best fit"; produces the typed STAR Suitability (S)…
alirezarezvani/claude-skills
Suggest, pick, or vet a business, startup, or product name that stays true to the founder's cultural origin while working professionally in the markets they want to sell into.
huifer/WellAlly-health
分析运动数据、识别运动模式、评估健身进展,并提供个性化训练建议。支持与慢性病数据的关联分析. An agent skill from huifer/WellAlly-health.
tamdogood/builder-essential-skills
Create truthful, human-centered marketing campaigns for an app or product, including positioning, channel copy, original artwork, editable layouts, README banners, and selective website integration.
tamdogood/builder-essential-skills
Generate, refine, compare, and when needed validate distinctive names for startups, AI products, developer tools, protocols, open-source projects, apps, product families, local businesses, services…
tamdogood/builder-essential-skills
Profile and debug Hermes sessions from their JSONL transcripts.
tamdogood/builder-essential-skills
Inspect an unfamiliar repository, turn a focused Markdown behavior scenario into a deterministic test in the repository's native test stack, run it, and preserve traceability between intent and code.
tamdogood/builder-essential-skills
Create or update a complete repository skill from a user's idea, including the workflow instructions, references, scripts or assets, agent metadata, skill-card artwork, cinematic banner artwork…
tamdogood/builder-essential-skills
Run a cumulative daily or retrospective sweep of research papers on a chosen topic, audit their claims, methods, integrity signals, and independent support, then identify overlooked but feasible…
Run an honest market-fit and viability audit of any project or idea and produce a decision doc, not code. Validate Market is an agent skill from tamdogood/builder-essential-skills. Run an honest market-fit and viability audit of any project or idea and produce a decision doc, not code.
Validate Market fits situations like: someone asks is this viable as a business; audit the market fit; make the case and compare to competitors; should I apply to YC.
Run `npx skills add tamdogood/builder-essential-skills --skill validate-market -a claude-code`. Or copy the skill folder (skills/validate-market in tamdogood/builder-essential-skills) into .claude/skills/validate-market in your project. Claude Code loads it when a task matches its description.
Run `npx skills add tamdogood/builder-essential-skills --skill validate-market -a codex`. Or copy the skill folder (skills/validate-market in tamdogood/builder-essential-skills) into .agents/skills/validate-market in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add tamdogood/builder-essential-skills --skill validate-market -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/validate-market, .gemini/skills/validate-market, .github/skills/validate-market and .opencode/skills/validate-market in your project.
Going by SKILL.md and its folder, Validate Market needs the command-line tools its instructions call (gh and codex). Its frontmatter pre-approves these tools: Read, Write, Edit, Grep, Glob, Bash, WebSearch, WebFetch, Agent, AskUserQuestion. Compatibility (from SKILL.md): claude-code.
SKILL.md contains no URLs. Its commands use gh, which can reach the network depending on how they are called. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found notes only (pre-approves every shell command (allowed-tools: bash)), nothing it rates as a warning. It is not a guarantee. Review the folder before installing.
Validate Market is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
About 2.8k tokens (SKILL.md is roughly 11k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
Skills that share tags, products or a category with Validate Market: Table Fit (asgeirtj/system_prompts_leaks, 69k stars), Furniture Fit Check (pascalorg/editor, 25k stars), Fitness Program (revfactory/harness-100, 1.3k stars) and Fit Scorer (aaron-he-zhu/aaron-marketing-skills, 2.9k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
tamdogood (a GitHub user) maintains it in tamdogood/builder-essential-skills, which has 221 GitHub stars. The repository holds 18 skills in this directory. The repository was last updated on August 16, 2026.
Source: tamdogood/builder-essential-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.