x402 Wallet
NPM · @THREE-WS/X402-MCP · SCANNED SEP 20
Self-custodial x402 wallet for AI agents: pay any service in USDC or $THREE from your own key.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security90
- No malware found by supply-chain analysis.Pass
- CVE check failed: a known high-severity CVE affects uuid 8.3.2, reached via @solana/web3.js > jayson > uuid. A fixed version is available. View diagnostics → Fail
- No install/post-install scripts declared.Pass
- 54 of 217 dependencies flagged as unhealthy (2 deprecated). View diagnostics → Partial
Provenance & Transparency35
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- License check failed: the license (SEE LICENSE IN LICENSE) isn't a recognized OSI-approved license. See how to fix → Fail
- Actively maintained (last published 8 days ago).Pass
- Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability68
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 902 tokens (~225/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management80
- Stability observed for 24 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.Pass
- An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
How do I install the x402 Wallet MCP server?
x402 Wallet runs locally as an npm package, launched with npx -y @three-ws/x402-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · @three-ws/x402-mcp
claude mcp add nirholas-x402-mcp -- npx -y @three-ws/x402-mcp
{
"mcpServers": {
"nirholas-x402-mcp": {
"command": "npx",
"args": [
"-y",
"@three-ws/x402-mcp"
]
}
}
} {
"servers": {
"nirholas-x402-mcp": {
"command": "npx",
"args": [
"-y",
"@three-ws/x402-mcp"
]
}
}
} codex mcp add nirholas-x402-mcp -- npx -y @three-ws/x402-mcp
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"nirholas-x402-mcp": {
"type": "local",
"command": [
"npx",
"-y",
"@three-ws/x402-mcp"
],
"enabled": true
}
}
} openclaw mcp add nirholas-x402-mcp --command npx --arg -y --arg @three-ws/x402-mcp
mcp_servers:
nirholas-x402-mcp:
command: "npx"
args: ["-y", "@three-ws/x402-mcp"] {
"McpServers": {
"nirholas-x402-mcp": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@three-ws/x402-mcp"
]
}
}
} assistant mcp add nirholas-x402-mcp -t stdio -c npx -a -y @three-ws/x402-mcp
{
"mcpServers": {
"nirholas-x402-mcp": {
"command": "npx",
"args": [
"-y",
"@three-ws/x402-mcp"
]
}
}
} Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 19 Sept 26 −3
- Stability: pass → 0.77 functional
- 18 Sept 26 0
- Stability: 0.97 → pass security
- 17 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.
- 15 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.
- 13 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 80 to 83. That category is still filling its 30-day observation window: 24 days of observed history at the previous scan, 25 at this one. The score rises as the window fills, whether or not the server changes.
- 12 Sept 26 −3
- Stability: pass → 0.80 functional
- 11 Sept 26 0
- Stability: 0.97 → pass security
- 10 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 20 Sept 2026 · Analysed npm/@three-ws/x402-mcp@0.2.2
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Vulnerabilities 3 findings
| ID | CVE | Severity | Vector | Fix available |
|---|---|---|---|---|
| GHSA-3gc7-fjrx-p6mg | CVE-2025-3194 | high | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | no |
| GHSA-528h-pc64-c93x | CVE-2026-71429 | medium | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | yes |
| GHSA-w5hq-g745-h8pq | CVE-2026-41907 | high | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N | yes |
Background: What a vulnerability scan can and cannot prove →
Dependencies 217 packages
| Packages resolved | 217 |
|---|---|
| Deprecated | 2 |
| Stale | 52 |
| No linked repository | 1 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
find_services Find paid x402 services the agent can call ~160
Search the live x402 facilitator network (PayAI + Coinbase CDP bazaar) for paid services — HTTP APIs and MCP tools. Returns each match with its price, networks, and resource URL. Pass a resource into pay_and_call to use it. Read-only.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | Max results (default 25). |
| max_price_usdc | number | – | Only return services at or under this USDC price. |
| network | string | – | CAIP-2 network filter, e.g. "solana:*" or "eip155:8453". |
| query | string | yes | What you need, e.g. "weather", "image upscale", "token intel". |
| type | string | – | Service kind to search. |
No output schema declared.
No examples provided.
inspect_endpoint Inspect an x402 endpoint (price + requirements, no payment) ~103
Fetch an x402 endpoint and return its 402 payment requirements — every accepted scheme, network, asset, price and pay-to address — WITHOUT paying. If the endpoint is free, returns its result instead. No signer required. Use this to learn the cost before pay_and_call.
| Name | Type | Req | Description |
|---|---|---|---|
| body | object | – | JSON body for a POST probe. |
| method | string | – | HTTP method to probe with. |
| url | string | yes | The x402 endpoint URL to inspect. |
No output schema declared.
No examples provided.
pay_and_call Pay an x402 endpoint in USDC or $THREE and return its result ~403
Call a paid x402 endpoint and settle the payment automatically, then return the result. Two modes: • Self-custodial (default): signs with SOLANA_SECRET_KEY or `secret` arg — you hold the key. • Session-governed: pass `session_token` (a three.ws Payment Session token) — the platform wallet signs on your behalf; the session's budget, allowlist, and per-tx cap are enforced by the platform. No private key required. Supports Solana USDC and Base USDC sessions. Pay in USDC (default) or, when the endpoint advertises it, in $THREE (set token:"three"). Bounded by max_usd and the MAX_PAY_USD cap; refuses before any money moves if the price is over the cap. With REQUIRE_CONFIRM on, the call refuses until re-issued with confirm:true.
| Name | Type | Req | Description |
|---|---|---|---|
| body | object | – | JSON body for POST requests. |
| confirm | boolean | – | Must be true to execute when REQUIRE_CONFIRM is on. |
| idempotency_key | string | – | Deduplication key for this call. Recommended when using session_token to avoid double-charges on retries. |
| max_usd | number | – | Hard ceiling for THIS call in USD. Can only lower the MAX_PAY_USD cap, never raise it. |
| method | string | – | HTTP method. |
| secret | string | – | Per-call base58 signer override (defaults to SOLANA_SECRET_KEY). Ignored when session_token is set. |
| session_token | string | – | three.ws Payment Session token (pss_…). When provided, the platform wallet pays — no local key needed. Overrides `secret`. |
| token | string | – | Settlement token. "usdc" (default) or "three" — the $THREE platform token; the endpoint must advertise it. Ignored when session_token is set. |
| url | string | yes | The x402 endpoint to pay and call. |
No output schema declared.
No examples provided.
x402_wallet The agent's x402 spending wallet (address + balance) ~87
Show a Solana wallet's address and live SOL + USDC balance. With no `address`, derives the wallet from the configured signer (SOLANA_SECRET_KEY) — call this before pay_and_call to confirm there's USDC to spend. Read-only; never moves funds.
| Name | Type | Req | Description |
|---|---|---|---|
| address | string | – | Base58 Solana address to inspect. Omit to use the configured signer wallet. |
No output schema declared.
No examples provided.
What is the x402 Wallet MCP server?
x402 Wallet is an MCP server listed in the public MCP registry as io.github.nirholas/x402-mcp. Self-custodial x402 wallet for AI agents: pay any service in USDC or $THREE from your own key. This page covers its npm package (@three-ws/x402-mcp).
Is the x402 Wallet MCP server safe to use?
x402 Wallet scores 75 out of 100 on VerifyMCP. We recorded 3 known advisories against it as of 20 September 2026. It declares no install or post-install scripts. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the x402 Wallet MCP server expose?
x402 Wallet exposes 4 tools: x402_wallet, find_services, inspect_endpoint, pay_and_call. Their descriptions and schemas cost roughly 753 tokens of context every time the server is loaded.
Is the x402 Wallet MCP server still maintained?
x402 Wallet is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.