ProvenPaid
Check an x402 endpoint before your agent pays it: challenge validity and on-chain payer evidence.
Installation
Ajoutez ceci à la configuration MCP de votre client (Claude Desktop : claude_desktop_config.json ; Cursor : .cursor/mcp.json ; VS Code et les autres utilisent la même forme « mcpServers »).
provenpaid-mcpclaude mcp add provenpaid -e 'PROVENPAID_WALLET_PRIVATE_KEY=<your provenpaid_wallet_private_key>' -e 'PROVENPAID_DAILY_LIMIT=<PROVENPAID_DAILY_LIMIT>' -e 'PROVENPAID_MAX_PRICE_USD=<PROVENPAID_MAX_PRICE_USD>' -- uvx provenpaid-mcp==0.2.0
{
"mcpServers": {
"provenpaid": {
"command": "uvx",
"args": [
"provenpaid-mcp==0.2.0"
],
"env": {
"PROVENPAID_WALLET_PRIVATE_KEY": "<your provenpaid_wallet_private_key>",
"PROVENPAID_DAILY_LIMIT": "<PROVENPAID_DAILY_LIMIT>",
"PROVENPAID_MAX_PRICE_USD": "<PROVENPAID_MAX_PRICE_USD>"
}
}
}
}
Variables d'environnement
PROVENPAID_WALLET_PRIVATE_KEYsecret Optional. Private key of a dedicated low-balance wallet holding USDC on Base, used only to sign payments after the 10 free checks. Not needed to try it.PROVENPAID_DAILY_LIMITMaximum paid checks per UTC day (default 20).PROVENPAID_MAX_PRICE_USDRefuse checks priced above this (default 0.01, hard ceiling 0.10).
Documentation
Tirée du README du projet sur GitHub, actualisée chaque semaine. Les liens ouvrent GitHub.
provenpaid-mcp
Give your agent a pre-payment check for paid x402 endpoints. Evidence before you pay.
ProvenPaid checks an x402 endpoint before your agent relies on it: is its payment challenge valid, and do real wallets actually pay it on-chain, come back, and how concentrated are payments? This MCP server exposes that check as a tool. The first 10 checks are free, with no wallet and no setup. After that it pays automatically, about $0.01 in USDC on Base per check, from a wallet you control.
Use it once before relying on an unfamiliar endpoint, not before every call.
Tools
| Tool | Cost | What it does |
|---|---|---|
check_x402_endpoint(url) | first 10 free, then about $0.01 | Validates the endpoint's x402 challenge and reports public on-chain evidence for its receiving address: distinct payers, repeat-payer share, payer concentration, coverage. |
provenpaid_methodology() | free | How each signal is computed, what is not verified, and when a check is charged. |
provenpaid_status() | free | Free checks left, paying wallet address, network, price cap and paid checks left today. |
You are not charged when the URL is invalid or unsafe, is not an x402 endpoint, or offers no payment option in USDC on Base. Results are evidence, not a verdict: ProvenPaid does not verify service quality or that an endpoint controls its receiving address.
Install
Requires Python 3.11+. With uv:
uvx provenpaid-mcp
or pip install provenpaid-mcp.
Try it free (no wallet)
{
"mcpServers": {
"provenpaid": { "command": "uvx", "args": ["provenpaid-mcp"] }
}
}
On first run it creates a local identity key (~/.provenpaid-mcp/identity.key, owner-only). The key holds no funds; it only lets ProvenPaid count your 10 free checks. Only checks that return evidence count.
Keep going after the free checks
Add a dedicated, low-balance wallet:
{
"mcpServers": {
"provenpaid": {
"command": "uvx",
"args": ["provenpaid-mcp"],
"env": {
"PROVENPAID_WALLET_PRIVATE_KEY": "0x...",
"PROVENPAID_DAILY_LIMIT": "20"
}
}
}
}
Wallet safety
- Use a dedicated wallet holding only a few dollars of USDC on Base. Never use a wallet with meaningful funds.
- The key stays on your machine, in memory only. It is never logged, returned by a tool, or sent anywhere; only signed payment authorizations leave the process.
- No ETH is needed: the payment facilitator pays network fees.
Guardrails enforced before anything is signed:
| Setting | Default | Meaning |
|---|---|---|
PROVENPAID_MAX_PRICE_USD | 0.01 | Refuse any check priced above this (hard ceiling 0.10). |
PROVENPAID_DAILY_LIMIT | 20 | Maximum paid checks per UTC day, persisted across restarts. |
PROVENPAID_NETWORK | eip155:8453 | Pay only on this network, only in its USDC. eip155:84532 for Base Sepolia testing. |
PROVENPAID_API_URL | https://api.provenpaid.com | Must be https. |
PROVENPAID_STATE_DIR | ~/.provenpaid-mcp | Where the daily counter is kept. |
How it works
The server calls GET https://api.provenpaid.com/v1/check?url=.... The API answers HTTP 402 with x402 payment requirements; the official x402 SDK signs a single-use USDC authorization within the guardrails above and retries. Settlement happens only when the check delivers evidence. Methodology: https://api.provenpaid.com/methodology
License
MIT
Questions fréquentes
Qu'est-ce que ProvenPaid ?
Check an x402 endpoint before your agent pays it: challenge validity and on-chain payer evidence.
Comment installer ProvenPaid ?
Il s'exécute sur votre machine. Dans Claude Code : claude mcp add provenpaid -e 'PROVENPAID_WALLET_PRIVATE_KEY=<your provenpaid_wallet_private_key>' -e 'PROVENPAID_DAILY_LIMIT=<PROVENPAID_DAILY_LIMIT>' -e 'PROVENPAID_MAX_PRICE_USD=<PROVENPAID_MAX_PRICE_USD>' -- uvx provenpaid-mcp==0.2.0. Pour les autres clients, collez la configuration JSON de cette page dans leurs réglages MCP.
Faut-il une clé API pour ProvenPaid ?
Oui. Il attend PROVENPAID_WALLET_PRIVATE_KEY, à renseigner dans sa configuration.
ProvenPaid est-il open source ?
Oui. Son code est sur GitHub sous licence MIT.
Qui maintient ProvenPaid ?
Il est publié par justinsmithphd. AI.tn le référence sans le maintenir ni le recommander.
Issu du registre MCP officiel. Être listé n'est pas une recommandation : vérifiez le code et les permissions d'un serveur avant de lui donner accès à vos données.