A guide for choosing the right domain ending, or TLD, for a project. It explains options such as .com, .io, .dev, and .ai using the project's audience, category, brand fit, and infrastructure needs.

Use it to compare domain endings for developer tools, AI products, SaaS, APIs, creative work, open-source projects, games, or local businesses.

It reduces guesswork when deciding whether a domain ending fits a product or audience. It also helps answer factual questions about TLD registration and lookup support.

tld-advisor — Skill for Claude Code by kemalabuteliyte

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 kemalabuteliyte/domain-whois-mcp --skill tld-advisor

Clone the repo

git clone --depth 1 https://github.com/kemalabuteliyte/domain-whois-mcp

Made for: Claude Code.

Or install domain-whois-mcp, the plugin that ships this one along with the rest of its 4 skills, 4 commands, 1 agent, 1 MCP server.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor/github.svg)](https://agentmods.dev/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor)

Your own site

<a href="https://agentmods.dev/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor"><img src="https://agentmods.dev/badge/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor"><img src="https://agentmods.dev/badge/skills/kemalabuteliyte/domain-whois-mcp/tld-advisor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 88 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 654 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.

Model	Per session	Once invoked
Fable 5.1	$0.00088	$0.00654
Opus 5	$0.00044	$0.00327
Sonnet 5	$0.00018	$0.00131
Haiku 4.5	$0.00009	$0.00065

Measured 11d ago against content hash 01f16ba745fe, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

tld-advisor 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/tld-advisor/SKILL.md · 47 lines

What it actually says

TLD Advisor

Help the user pick the right TLD. Blends factual infrastructure data (from tld_info / rdap_bootstrap_info) with opinionated category guidance.

When to Use

"Should I register .io or .dev?"
"Is .ai worth the premium?"
"What TLDs are good for a SaaS product?"
"Does .xyz look professional?"
"What WHOIS server does .tr use?" (factual — route to domain-lookup)

Category → TLD guidance (opinionated)

Category	First choice	Fallback	Avoid
Dev tool / CLI / library	`.dev`	`.io`, `.sh`	`.biz`
AI product	`.ai`	`.com`, `.app`	`.ml` (now retired)
Consumer SaaS	`.com`	`.co`, `.app`	`.click`, `.top`
API / infra	`.io`	`.dev`, `.cloud`	`.info`
Creative / portfolio	`.design`, `.studio`, `.me`	`.co`	—
Open source project	`.org`, `.dev`	`.io`	—
Gaming	`.gg`, `.games`	`.io`	—
Local business	ccTLD (`.de`, `.fr`, …)	`.com`	—

.com is still the safest default. If unavailable, .co and .app read professionally; .io and .dev signal "technical" — not always what you want for consumer products.

Workflow

If user names a TLD, call tld_info for that TLD. Report WHOIS server, RDAP server, IDN support.
If user is choosing between TLDs, produce the comparison table above with their category highlighted.
Call rdap_bootstrap_info if user asks about RDAP support specifically.

Flags worth mentioning

TLDs that don't publish public WHOIS (some ccTLDs) — harder to research owner info
TLDs with high premium pricing (.ai, .io, .dev can be $60–$100/yr vs .com at ~$12)
TLDs that have been flagged by some email providers as spam-adjacent (.top, .click, .xyz has improved but still mixed reputation)
Retired TLDs — don't recommend anything that's been deprecated by its registry

Be specific. Don't hedge with "it depends" — the user asked you to recommend.

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.

11d ago First seen · 47 lines · 88 tokens per session scan A 01f16ba745fe

Subscribe to this mod's changes

tld-advisor is a skill published in the GitHub repository kemalabuteliyte/domain-whois-mcp (0 stars, last pushed 4mo ago), licensed MIT. It adds 88 tokens to every session and 654 once invoked, about $0.0004 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.

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