Spec Driven Development
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Description from the maker (original English)
Company facts for AI agents: which vendors a company uses, proven from DNS. Paid in USDC.
These three are never merged into one score: opinions, measurements and popularity are different things.
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
Pick the AI app you use, then copy the settings.
HOSAKA_PRIVATE_KEY, HOSAKA_URLValues marked secret are keys to your account. Never share them or paste them into a chat.
You need
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json
{
"mcpServers": {
"hosaka": {
"command": "npx",
"args": [
"-y",
"hosaka-mcp"
],
"env": {
"HOSAKA_PRIVATE_KEY": "your-value",
"HOSAKA_URL": "your-value"
}
}
}
}Run this in your terminal
claude mcp add hosaka --env HOSAKA_PRIVATE_KEY=your-value --env HOSAKA_URL=your-value -- npx -y hosaka-mcpFill in the empty values before running it.
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"hosaka": {
"command": "npx",
"args": [
"-y",
"hosaka-mcp"
],
"env": {
"HOSAKA_PRIVATE_KEY": "your-value",
"HOSAKA_URL": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Paste into .vscode/mcp.json in your project
{
"servers": {
"hosaka": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"hosaka-mcp"
],
"env": {
"HOSAKA_PRIVATE_KEY": "your-value",
"HOSAKA_URL": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.
Your choice stays on this device in a cookie; no account needed.
HOSAKA_URL envThese settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
Runs on your computer; the tool list appears in your AI app after you install it.
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026
The registry name was verified with the GitHub account plus8bit, which owns the repo
We have not read this repo from GitHub yet
We have not read this repo from GitHub yet
This one runs on your computer; there is no internet endpoint
Runs on your computer and uses local settings instead
Runs on your computer; we can only read tool lists from internet endpoints
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
You need to fill in: HOSAKA_PRIVATE_KEY
It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).
The GitHub repo last changed –, and the latest version (0.3.2) reached the registry 2 months ago.
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.
In the same category: Spec Driven Development, Remote Desktop Commander, TF Rooms
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.
Live room availability, rates and stay quotes for 12 New Leaf motels in Twin Falls, Idaho.
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
Two services that sell to AI agents over x402, paid per call in USDC. No signup, no API key, no subscription — an agent calls, pays, and gets an answer.
| what it sells | price | |
|---|---|---|
| Hosaka | which third-party vendors a company uses, proven from its own DNS, plus contacts | $0.005 – $0.40 |
| deadchannel | whether an x402 endpoint is alive, honestly priced and safe to call | $0.005 |
Agents can install Hosaka as a skill, which tells them what it is for and when to reach for it:
npx skills add plus8bit/deadchannel/skills/hosaka --yes
Available as an MCP server, so any MCP client can buy from it directly:
npx -y hosaka-mcp
{
"mcpServers": { "hosaka": { "command": "npx", "args": ["-y", "hosaka-mcp"], "env": { "HOSAKA_PRIVATE_KEY": "0x…" } } } }
HOSAKA_PRIVATE_KEY is a wallet holding a little USDC on Base. Four tools at four prices, so a cheap question never pays for an expensive answer:
| tool | price | what you get |
|---|---|---|
hosaka_lookup | $0.005 | domain age, registrar, mail and DNS provider, DMARC, HTTPS, vendor count |
hosaka_contacts | $0.02 | the dossier, plus the emails and phones the company publishes about itself |
hosaka_dossier | $0.02 | every third-party vendor the company can be proven to use, each with its proof |
hosaka_people | $0.35 | the dossier, plus named people who work there |
Why the dossier is worth having. A company proves it owns its domain to every SaaS product it buys by placing a DNS verification record, and authorises every sender it uses in its SPF record. Those two lists are a purchase history the company published itself.
Asking for figma.com returns Anthropic, OpenAI, Adobe, Atlassian, MongoDB Atlas, Greenhouse, Docusign, Stripe, Notion, Dropbox and Zendesk — each with the exact record that proves it, so a buyer can check rather than trust.
Page fingerprints require a loaded script or CDN host, never a mention: a site listing a vendor's logo among its integrations is not a site that uses it.
Live at hosaka-agents.vercel.app.
Give it a URL, it tells an agent whether that endpoint is alive, honestly priced, and safe to call — without spending a cent.
Roughly 17% of probed x402 endpoints are dead or traps, and the Bazaar discovery layer ships no ranking, quality, or reputation signal by its own admission. An agent picking from that catalog is guessing with real money.
Every verdict comes from unpaid 402 responses, which is what makes it cheap enough to run across a whole catalog.
| Signal | What it catches |
|---|---|
reachable | Endpoint answers at all, consistently |
bot-gate | A bot wall answers agents while browsers get a clean 402 — the endpoint is invisible to indexers |
speaks-402 | Returns parseable payment requirements (v1 body and v2 payment-required header) |
gate-closed | Advertises a price it does not enforce — anyone can take the content free |
price-sane | Price sits inside $0.0001–$5; above the ceiling one call can drain a budget |
price-stable | Quote does not move between probes taken seconds apart |
pay-to-valid | Payout address is well formed for its chain and is not a burn address |
network-mainnet | Settles somewhere that can hold real value, not testnet only |
network-known | Chain identifier is recognizable (CAIP-2 or friendly name) |
schema-advertised | Agent can know the response shape *before* paying |
bazaar-metadata | Publishes serviceName / tags so topic search can find it |
latency | p99 inside the 5s budget agents typically allow |
spec-clean | Payload matches the documented shape; deviations are reported, not swallowed |
Verdicts: live, degraded, trap, testnet, dead, unknown, plus a bounded 0–100 risk score.
Requires Node 22+. There are no runtime dependencies — types are stripped natively, so there is no build step and nothing to audit but this repo.
node src/cli.ts https://x402.org/protected
node src/cli.ts --quiet --samples 5 url-a url-b url-c node src/cli.ts --json url > verdict.json
Exit code is non-zero when any target is a trap or dead, so it drops into CI as a guard against shipping an agent pointed at a bad endpoint.
TESTNET risk 80 $0.01 355ms p99 https://x402.org/protected
x network-mainnet Only testnet networks offered (base-sepolia, solana-devnet). This endpoint cannot accept real value. ! schema-advertised No input or output schema. An agent has to pay before it can find out what it gets back.
node src/scan.ts --live 150 pulls every resource the public Bazaar facilitators publish and audits it. Results over 14,979 resources:
| catalog held by the top 3 payout addresses | 18.4%, receiving 1 call in 80 |
| publish no discovery tags | 40.9% — an agent searching by topic never finds them |
| pass every check | 56.8% |
| of the 150 busiest, live right now | 91.3% |
| of the busiest, genuinely dead | 2.0% |
Median price $0.01, range $0 to $1,000, 316,927 paid calls in 30 days.
The catalog is in better shape than the folklore suggests. What it is not is evenly distributed: three addresses list 2,750 resources between them and receive one call in eighty, which makes them roughly 15x over-represented relative to the demand they serve. Catalog size is not catalog depth.
An earlier version of this table claimed 89.8% of the catalog published no tags. That was wrong. The loader read extensions.bazaar.tags only, while most publishers put tags on the item root — the real figure is 40.9%.
The bug survived review because nothing asserted the *positive* count. A check that only ever counts what is missing cannot tell "publishers omit this" apart from "we are looking in the wrong place." test/catalog.test.ts now hand-counts tags across all three known locations in a captured 200-item slice of the live catalog and asserts the loader matches exactly, in both directions.
Built against live endpoints, not the spec alone:
{}. A parser that only reads the body marks the official reference endpoint as dead.eip155:84532, solana:EtWTRA…) where v1 sent friendly names. Both are live simultaneously.resource metadata to the payload root.x402Version the reference implementations all send, and some nest accepts[] one level deeper than documented. Both are parsed and reported as warnings rather than rejected.serviceName/tags on the ResourceInfo object, the CDP catalog flattens them onto the item root, and a minority nest them under extensions.bazaar. Read one location and you will undercount by half.aws:base network instead of a chain address. That is legitimate, but the funds go to the broker, so it is reported as a warning rather than scored as an invalid payout.The service sells its own check over x402. src/server/ implements the seller side of the v2 HTTP transport: PAYMENT-REQUIRED out, PAYMENT-SIGNATURE in, PAYMENT-RESPONSE back, in the authorization flow — verify, run the resource, then settle.
No private key is involved. A seller declares where settlement should land; the buyer signs and the facilitator broadcasts. The payout address is therefore public information and lives in deadchannel.config.json, where anyone can audit it, rather than in a dashboard where nobody can.
Settlement runs only after the probe produced a result, so a failure on our side costs the buyer nothing.
GET / service card, free
GET /health liveness, free GET /facilitator proves credentials are accepted, free, moves no money POST /probe the check, $0.005 in USDC on Base
GET /facilitator exists because a wrong credential otherwise stays invisible until someone tries to pay, and the first to discover it would be a customer.
The service is deployed at https://deadchannel.vercel.app, selling on Base mainnet at $0.005 per call and settling through the Coinbase facilitator.
First settled payment: 0x6ac4a22c, block 50230005, 20 Aug 2026. Gas was paid by the facilitator, not the buyer — in x402 the buyer only signs, so a wallet holding nothing but USDC can pay.
npm run validate re-runs the 25 preflight checks the Bazaar applies before it will index a resource, and reports whether the listing is currently active. It needs no key and moves no money.
resource : https://deadchannel.vercel.app/probe
valid : true accepted : accepted checks : 25/25 passed indexed : active=true
A second shop on the same payout address, selling company facts to agents.
POST /lookup $0.005 domain age, registrar, mail and DNS provider, DMARC, HTTPS
POST /dossier $0.02 every third-party vendor we can prove, with the proof
Live at https://hosaka-agents.vercel.app, settling on Base mainnet.
Profiles are assembled from four sources that need no key and no supplier: DNS over HTTPS, the RDAP registry, the TLS handshake and the homepage. Cost per profile is zero — the margin is in the assembly.
The interesting part is vendor detection. A company proves ownership to every SaaS product it buys by placing a DNS verification record, and authorises every sender it uses in its SPF record. Those two lists are a purchase history the company published itself. Every claim carries the record that proves it, so a buyer can check rather than trust.
The Bazaar's search ignores the query and ranks by unique payers, so a new shop is invisible there regardless of quality. MCP is the channel that works on day one — the agent is already in a client that speaks it.
{
"mcpServers": { "hosaka": { "command": "node", "args": ["/absolute/path/to/src/hosaka/mcp/server.ts"], "env": { "HOSAKA_PRIVATE_KEY": "0x…" } } } }
The buyer brings their own wallet: the key signs the payment locally and never leaves the machine. Without it the tools say what is missing instead of failing mid-conversation.
npm install # typescript only, for typechecking
npm test # 18 tests, no network required npm run typecheck
MIT