Spec Driven Development
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Description from the maker (original English)
Virtual Visa cards for AI agents. JIT card issuance, human-approved, MCP-native.
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.
PAYCLAW_API_KEY, PAYCLAW_API_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": {
"payclaw": {
"command": "npx",
"args": [
"-y",
"@payclaw/mcp-server"
],
"env": {
"PAYCLAW_API_KEY": "your-value",
"PAYCLAW_API_URL": "your-value"
}
}
}
}Run this in your terminal
claude mcp add payclaw --env PAYCLAW_API_KEY=your-value --env PAYCLAW_API_URL=your-value -- npx -y @payclaw/mcp-serverFill in the empty values before running it.
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"payclaw": {
"command": "npx",
"args": [
"-y",
"@payclaw/mcp-server"
],
"env": {
"PAYCLAW_API_KEY": "your-value",
"PAYCLAW_API_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": {
"payclaw": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@payclaw/mcp-server"
],
"env": {
"PAYCLAW_API_KEY": "your-value",
"PAYCLAW_API_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.
PAYCLAW_API_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 6, 2026
The registry name was verified with the GitHub account payclaw, 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: PAYCLAW_API_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 (0.1.4) reached the registry 8 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, debuff
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.
Let coding agents play, test and tune your 2D web game: live state, explained errors, replays, fuzz.
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.
Your agent isn't a bot. kya proves it — then lets it pay.
Your AI agent looks like a bot to every merchant on the internet. kya gives it two things:
Badge — Declares your agent as an authorized actor. The Universal Commerce Protocol "identity" token for a merchant handshake. Free. No card required.
Spend — Issues a single-use virtual Visa when your agent needs to pay. Human-approved. Self-destructs after use. Your real card never enters the chat.
If you're like 20% of Americans last year - you used an agent to shop. And you probably ran into a ton of login walls, workarounds, bumps?
So did we. So we created kya - the first MCP tool suite that works with the new Universal Commerce Protocol to easily handshake verified agents at supporting merchants (Shopify, Target, Walmart, Etsy... it's a lot). Badge for identity. Spend for payment.
🧪 Developer Sandbox is open. Real infrastructure, test money. Get sandbox access →
npx @kyalabs/mcp-server
OR add to your MCP client config (Claude Desktop, Cursor, or any MCP client):
{
"mcpServers": { "kyalabs": { "command": "npx", "args": ["@kyalabs/mcp-server"] } } }
That's it. Badge works immediately — no API key, no signup, no network calls on install.
The first time your agent calls kya_getAgentIdentity, it declares itself to the merchant and gets back a response with next_step guidance. One anonymous event is recorded. Your agent is now a declared, authorized actor.
Or install via ClawHub:
clawhub install payclaw-io
For cryptographic identity and virtual card issuance, add an API key:
"env": {
"KYA_API_KEY": "pk_live_your_key_here", "KYA_API_URL": "https://www.kyalabs.io" }
Get your API key at kyalabs.io/signup. API keys don't expire.
Without an API key, Badge uses device auth when a merchant requires verified identity — your agent shows a code and URL, you approve on your phone. This only happens when a merchant asks for it. We never ask for it ourselves. Sign up + API key means 1. you dont have to use phone OAuth every time and 2. you can track your agentic shopping (custom avatars included)
kya MCP requires Node.js 20 or newer. Node 18 is end-of-life and unsupported.
If you see engine or compatibility errors: node -v — install Node 20+ from nodejs.org or nvm install 20
First time your agent goes to a merchant with Badge, Badge generates an anonymous install ID — a random UUID stored locally at ~/.kya/install_id. It has no connection to you, your device, or any personal information.
Your agent gets back a declaration and a next_step guiding it to report its badge presentation at the merchant.
This is the default mode. It's how Badge works out of the box, for every user, forever.
When a merchant requires verified identity — their UCP manifest says required: true — your agent will ask you to approve a device flow. You visit a merchant-kya URL, enter the OAuth code from your agent, and prove you're a real person.
Badge issues a tokenized credential: an ES256-signed JWT, signed by kya's private key, verifiable locally by the merchant. Your agent is free to continue - no login, PII or anything needed.
| When | What | Why |
|---|---|---|
| On install | Nothing | We help agents shop. If they're not shopping, we don't need anything |
| On server start | Anonymous ping — Badge version and MCP client name. No identifiers stored on your machine | So we know Badge is actively running. If this number ever diverges from active agents, it tells us something is broken in the pipeline — not something about you |
| On first shopping trip | install_id (random UUID, stored locally at ~/.kya/install_id), merchant, agent_type, event_type, timestamp | Minimum viable signal to reduce agent friction at merchants |
| On verified identity | + hashed user token, intent scope (checkout, etc.) | Only required where login is traditionally required (i.e. checkout) to prove there's a real person authorizing the agent's next step |
| On Spend (card issuance) | + full transaction trail: intent, amount, merchant, audit log | Card network compliance, gated behind consent + MFA |
The server start ping contains no persistent identifiers — a new random session ID is generated each time and never saved to disk. You can disable it entirely:
"env": { "KYA_PING": "false" }
The install_id is a file we wrote to your disk. You can delete it (rm ~/.kya/install_id) and get a new one.
Full data practices: kyalabs.io/trust
Badge is a UCP (Universal Commerce Protocol) Credential Provider. Merchants who declare the kya identity extension signal to every UCP-compliant agent that authorized agents are preferred at their store.
When your agent encounters a UCP merchant with Badge installed, it presents a cryptographic badge automatically — no extra steps.
We believe the UCP is the future of commerce and are proud to support reduce friction for agents and users.
Without kya: Agent browses → bot detection fires → blocked. Even if it gets through, it can't check out without your real card number. You're stuck finishing manually.
With Badge: Agent declares itself as an authorized actor → merchants see a verified identity → agent gets through. No bypass. Just proof.
With Spend: Agent declares a purchase → you approve with a tap → kya issues a single-use virtual Visa locked to that merchant → agent checks out → card self-destructs. Your real card never enters the chat.
Your agent will recognize when it needs this. When it encounters a merchant that may challenge automated traffic, or when it's ready to check out, it tells you: "I need kya installed to complete this." You click Allow. Done.
See docs/tool-contract.md for the formal input/output contract.
| Tool | What It Does |
|---|---|
kya_getAgentIdentity | Declare identity → get verification token + next_step guidance (Badge) |
kya_reportBadgePresented | Record that you presented your badge at a merchant |
kya_reportBadgeOutcome | Report how the merchant responded (accepted, denied, inconclusive) |
kya_reportBadgeNotPresented | Report that you did not present your badge (abandoned, merchant didn't ask) |
kya_getCard | Declare purchase intent → get virtual Visa (Spend) |
kya_reportPurchase | Report transaction outcome → close the audit trail |
Every Badge tool call works immediately — no auth required. Events fire in both anonymous and verified modes.
Agent → kya_getAgentIdentity({ merchantUrl })
kya → browse_declared event fires automatically kya → verification token + next_step + checkoutPatch (if merchant supports UCP) Agent → merges checkoutPatch into checkout payload Agent → kya_reportBadgePresented({ merchantUrl, verification_token }) Agent → kya_reportBadgeOutcome (accepted | denied | inconclusive)
Agent → kya_getCard (merchant, amount, description)
User → approves via MFA kya → issues single-use virtual Visa Agent → uses card at checkout Agent → kya_reportPurchase (closes audit trail) Card → self-destructs
One task. One approval. One card. Done.
When enabled, kya checks back with your agent 7 seconds after each badge presentation to confirm whether the merchant accepted or denied. Results are logged to your dashboard so you can see when and which merchants are rejecting your agent.
"env": {
"KYA_EXTENDED_AUTH": "true" }
| Action | What Happens |
|---|---|
| Browse | Badge declaration — identity token issued |
| Search | Badge declaration — identity token issued |
| Checkout | Badge + Spend — MFA approval → single-use Visa issued |
Browsing requires declaration. Spending money requires declaration + stated intent + explicit human approval + an ephemeral card that self-destructs after one use.
| Give Agent Your Card | Crypto Wallet | kya | |
|---|---|---|---|
| Agent identity declared | No | No | Every session |
| Human approval per purchase | No | No | Every purchase |
| Card credential lifespan | Permanent | Permanent | Single use |
| Works at existing merchants | Yes | No | Yes — Visa rails |
| Your real card exposed | Yes | N/A | Never |
If you only need identity (no payment), use the lighter package:
npx @kyalabs/badge
| Capability | Description |
|---|---|
assurance_level | Every trip now carries a trust score (starter → elite) sourced from token introspection. Visible in your dashboard and included in all trip outcome events. |
| Merchant signal awareness | kya_getAgentIdentity now detects whether a merchant has active kya signal infrastructure (window.__kya_commerce, meta tags, llms.txt). Returned as merchant_signals in the identity result. |
| Anonymous-first | Badge works on install. No auth, no signup, no network on install. First kya_getAgentIdentity call fires browse_declared automatically. |
| Enrichment branching | Anonymous events fire without auth. Verified events include full user context. No silent gates. |
next_step field | Every identity response includes guidance for the agent's next action. Spend-aware when virtual cards are available. |
kya is KYA infrastructure. Every declaration creates a verified record of agentic commerce behavior — building the trust signal that merchants need to tell authorized agents from anonymous bots.
*Agents are not bots. kya labs proves it.* *Your real card never enters the chat.*