Agent skill

X402 Payments

Accept HTTP 402 cryptocurrency payments using Nethereum (.NET/C).

Install X402 Payments

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .claude/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .claude/skills/x402-payments && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .claude/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .agents/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .agents/skills/x402-payments && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .agents/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .cursor/skills/x402-payments && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .cursor/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/Nethereum/Nethereum.git --path plugins/nethereum-skills/skills/x402-payments

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .gemini/skills/x402-payments && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .gemini/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .github/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .github/skills/x402-payments && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .github/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add Nethereum/Nethereum --skill x402-payments -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install Nethereum/Nethereum x402-payments --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/Nethereum/Nethereum.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/plugins/nethereum-skills/skills/x402-payments .opencode/skills/x402-payments && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "x402-payments" agent skill from https://github.com/Nethereum/Nethereum/tree/master/plugins/nethereum-skills/skills/x402-payments into .opencode/skills/x402-payments/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "x402-payments", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: x402-payments
GitHub stars: 2.3k
Token cost: ~2.2k tokens
SKILL.md length: 479 words
Files: 1
Skills in repo: 71
Repo updated: Oct 5, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Accept HTTP 402 cryptocurrency payments using Nethereum (.NET/C).

The user asks about x402 protocol (version 2)
SKILL.md covers Client: Pay Automatically, Server: Protect Endpoints, Asset-Transfer Methods and Build EIP-3009 Authorizations…, plus 2 more sections
Calls dotnet; reaches facilitator.x402.org and mainnet.base.org
HTTP 402 payments

What it does

X402 Payments is an agent skill from Nethereum/Nethereum. Accept HTTP 402 cryptocurrency payments using Nethereum (.NET/C). Use this skill whenever the user asks about x402 protocol (version 2), HTTP 402 payments, pay-per-request APIs, EIP-3009 transfer authorization, Permit2 payments, USDC payments, crypto API monetization, payment middleware, or accepting cryptocurrency payments in ASP.NET with C or .NET.

Its SKILL.md is about 2.2k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Backend & APIs, covering Crypto and DeFi analysis and Authorization and RBAC. It works with x402, C#, .NET and ASP.NET Core. The repository describes itself as: Ethereum .Net cross platform integration library. The licence is MIT.

When your agent uses it

The user asks about x402 protocol (version 2)
HTTP 402 payments
Pay-per-request APIs
EIP-3009 transfer authorization

Example prompts

“/x402-payments”

What it can do on your machine

Read from SKILL.md and the folder at commit 229f278. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
- dotnet
From the folder's file list and the shell code blocks in SKILL.md.
Network
Hosts in commands or code, which the agent is likely to contact:
- facilitator.x402.org
- mainnet.base.org
Also links to:
- docs.nethereum.com
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

X402 Payments loads about 2.2k tokens when it runs. Until then it costs about 92 tokens; SKILL.md has 479 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~92
When it runs · the whole SKILL.md, loaded when a task matches: ~2.2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from Nethereum/Nethereum at commit 229f278, republished under its MIT licence (© Nethereum). 479 words, ~2,189 tokens.

Download SKILL.mdSave it as .claude/skills/x402-payments/SKILL.md (or your agent's skills folder).

name: x402-payments
description: Accept HTTP 402 cryptocurrency payments using Nethereum (.NET/C#). Use this skill whenever the user asks about x402 protocol (version 2), HTTP 402 payments, pay-per-request APIs, EIP-3009 transfer authorization, Permit2 payments, USDC payments, crypto API monetization, payment middleware, or accepting cryptocurrency payments in ASP.NET with C# or .NET.
user-invocable: true

x402: Crypto Payments (protocol v2)

The x402 protocol implements HTTP 402 (Payment Required) for pay-per-request APIs. A client pays with a signed authorization — off-chain (no gas) — and the server or a facilitator settles on-chain. Nethereum's Nethereum.X402 package provides X402HttpClient for automatic payments and X402Middleware for ASP.NET Core endpoint protection.

This library targets x402 version 2: payments carry x402Version = 2, the chosen requirement is echoed in the payload's accepted field, and networks use CAIP-2 identifiers (eip155:<chainId>, e.g. eip155:8453 for Base). The "exact" scheme supports two EVM asset-transfer methods: EIP-3009 (default) and Permit2.

NuGet: Nethereum.X402

bash

dotnet add package Nethereum.X402

The v2 wire uses three base64 headers: PAYMENT-REQUIRED (402 response), PAYMENT-SIGNATURE (request), PAYMENT-RESPONSE (200 response).

Client: Pay Automatically

X402HttpClient handles the full 402 flow — detect requirement, select one, sign it, retry with the payment header. The signing domain (token, chain id, name/version) is derived from the server's PaymentRequirements, so the client is not pre-configured with a token:

csharp

using Nethereum.X402.Client;

var options = new X402HttpClientOptions
{
    MaxAmount = "100000",           // Safety limit per request (USDC)
    PreferredNetwork = "eip155:8453",  // CAIP-2 (Base)
    PreferredScheme = "exact"
};

var x402Client = new X402HttpClient(httpClient, privateKey, options);
var response = await x402Client.GetAsync("https://api.example.com/premium/content");

// Check payment result from the PAYMENT-RESPONSE header
if (response.HasPaymentResponse())
{
    var txHash = response.GetTransactionHash();
    var payer = response.GetPayerAddress();
    var success = response.IsPaymentSuccessful();
}

Supports GetAsync, PostAsync, PutAsync, DeleteAsync, SendAsync. Throws X402PaymentExceedsMaximumException if the requested amount exceeds MaxAmount. The client automatically produces the right payload for the selected requirement's method (EIP-3009, or Permit2 when extra.assetTransferMethod == "permit2").

Manual Payment Flow

Construct with just the payer key and pass explicit PaymentRequirements:

csharp

var x402Client = new X402HttpClient(httpClient, privateKey);

var requirements = new PaymentRequirements
{
    Scheme = "exact",
    Network = "eip155:84532",   // Base Sepolia
    Amount = "1000000",         // $1.00 USDC (6 decimals), atomic units
    Asset = usdcAddress,
    PayTo = receiverAddress,
    MaxTimeoutSeconds = 60,
    Extra = new ExactSchemeExtra { Name = "USDC", Version = "2" }
};

var response = await x402Client.GetAsync("https://api.example.com/premium", requirements);

Server: Protect Endpoints

csharp

using Nethereum.X402.AspNetCore;
using Nethereum.X402.Server;
using Nethereum.X402.Models;

builder.Services.AddX402Services("https://facilitator.x402.org");

app.UseX402(options =>
{
    options.Routes.Add(new RoutePaymentConfig("/api/premium/*", new PaymentRequirements
    {
        Scheme = "exact",
        Network = "eip155:8453",
        Amount = "1000000",
        Asset = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        PayTo = "0xYourAddress",
        MaxTimeoutSeconds = 60,
        Extra = new ExactSchemeExtra { AssetTransferMethod = "eip3009", Name = "USDC", Version = "2" }
    }));
});

Self-Facilitated (No External Facilitator)

Settle on-chain directly. Only an RPC endpoint per chain id is configured (token/chain/domain come from each requirement):

csharp

using Nethereum.X402.Extensions;

var rpcByChainId = new Dictionary<int, string> { [8453] = "https://mainnet.base.org" };

// EIP-3009 only (facilitator pays gas):
builder.Services.AddX402TransferProcessor(facilitatorPrivateKey, rpcByChainId);

// EIP-3009 AND Permit2 (routes by payload shape) — recommended:
builder.Services.AddX402ExactProcessor(facilitatorPrivateKey, rpcByChainId);

// Receiver-submitted model (receiver pays gas):
builder.Services.AddX402ReceiveProcessor(receiverPrivateKey, rpcByChainId);

Each overload also accepts an IAccount (external signers/KMS) or an IServiceProvider factory.

Asset-Transfer Methods

Method	Processor	On-chain call
EIP-3009 (default)	`X402TransferWithAuthorisation3009Service`	`transferWithAuthorization`
EIP-3009 (receiver)	`X402ReceiveWithAuthorisation3009Service`	`receiveWithAuthorization`
Permit2	`X402ExactPermit2Service`	`x402ExactPermit2Proxy.settle`
dispatcher	`X402ExactSchemeProcessor`	routes by payload shape

All implement IX402PaymentProcessor (VerifyPaymentAsync, SettlePaymentAsync, GetSupportedAsync). A blockchain processor is constructed with a facilitator key (or IAccount) and a Dictionary<int, IClient> keyed by chain id.

Show full SKILL.md (192 more words)Show less

Permit2 Method

Permit2 works with any ERC-20 the payer has approved to the canonical Permit2 contract (no EIP-3009 support needed). A route opts in with extra.assetTransferMethod = "permit2"; the client signs a Permit2 PermitWitnessTransferFrom (spender = the x402ExactPermit2Proxy, witness = the recipient) and the facilitator settles via proxy.settle, which enforces that funds go only to that recipient:

csharp

options.Routes.Add(new RoutePaymentConfig("/api/premium-permit2", new PaymentRequirements
{
    Scheme = "exact",
    Network = "eip155:84532",
    Amount = "10000",
    Asset = usdcAddress,
    PayTo = receiverAddress,
    MaxTimeoutSeconds = 60,
    Extra = new ExactSchemeExtra { AssetTransferMethod = "permit2" }
}));

// Facilitator: X402ExactPermit2Service (or AddX402ExactProcessor to serve both methods)

The Permit2/proxy addresses are canonical constants (X402Permit2Addresses), the same on every EVM chain. The underlying Permit2 signing lives in Nethereum.Signer.EIP712/Nethereum.ABI, and the contract in Nethereum.Contracts (web3.Eth.GetPermit2Service()).

Build EIP-3009 Authorizations Directly

For custom flows:

csharp

using Nethereum.X402.Signers;

var builder = new TransferWithAuthorisationBuilder();
var signer = new TransferWithAuthorisationSigner();

var authorization = builder.BuildFromPaymentRequirements(requirements, payerAddress);
// Default window: validAfter = 10 min ago, validBefore = 1 hour from now

var signature = await signer.SignWithPrivateKeyAsync(
    authorization, "USD Coin", "2", chainId, usdcAddress, payerPrivateKey);

// Or sign with a Web3 account (hardware wallets, KMS)
var signature = await signer.SignWithWeb3Async(
    authorization, "USD Coin", "2", chainId, usdcAddress, web3, signerAddress);

Error Codes (`X402ErrorCodes`)

Code	Meaning
`invalid_exact_evm_insufficient_balance`	Payer doesn't have enough tokens
`invalid_exact_evm_signature`	EIP-3009 signature verification failed
`invalid_exact_evm_authorization_value`	Amount below the requirement
`invalid_exact_evm_recipient_mismatch`	Receiver mismatch
`invalid_exact_evm_nonce_already_used`	Nonce already used
`invalid_network` / `unsupported_payload_type`	Network/scheme not supported
`invalid_permit2_recipient_mismatch`	Permit2 witness recipient ≠ `PayTo`
`permit2_amount_mismatch` / `permit2_token_mismatch`	Permit2 amount/token mismatch
`permit2_allowance_required`	Payer hasn't approved Permit2 for the asset
`invalid_permit2_signature`	Permit2 signature verification failed

Supported Tokens

Any EIP-3009 token (for the eip3009 method) or any ERC-20 approved to Permit2 (for the permit2 method). Common USDC addresses:

Token	Network	Address
USDC	Ethereum	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48`
USDC	Base	`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`
USDC	Base Sepolia	`0x036CbD53842c5426634e7929541eC2318f3dCF7e`
USDC	Polygon	`0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359`
USDC	Arbitrum	`0xaf88d065e77c8cC2239327C5EDb3A432268e5831`
USDC	Optimism	`0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85`

For full documentation, see: https://docs.nethereum.com/docs/defi/guide-x402-payments

Files

Just SKILL.md in plugins/nethereum-skills/skills/x402-payments of Nethereum/Nethereum.

Open the folder on GitHubat commit 229f278

Compare with similar skills

X402 Payments next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

X402 Payments compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
X402 Payments this skillNethereum/Nethereum	2.3k	—	~2.2k	Automated safety check: Pass	MIT	4 days ago
Tsp Csharpquerylenshq/ef-querylens	225	—	~1.3k	Automated safety check: Pass	MIT	1 mo ago
Alchemy Agentic Gatewaymoonpay/skills	113	—	~2.1k	Automated safety check: Notes	MIT	29 days ago
Using Dotnetnovotnyllc/dotnet-artisan	233	—	~2.3k	Automated safety check: Warn	MIT	2 days ago
Dotnet Webapidotnet/skills	5.6k	2 repos	~5.5k	Automated safety check: Pass	MIT	today
C# and .NET DeveloperJeffallan/claude-skills	12k	—	~1.3k	Automated safety check: Pass	MIT	6 days ago

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Works with

Questions about X402 Payments

What does X402 Payments do?

Accept HTTP 402 cryptocurrency payments using Nethereum (.NET/C). X402 Payments is an agent skill from Nethereum/Nethereum.NET/C).

When should I use X402 Payments?

X402 Payments fits situations like: the user asks about x402 protocol (version 2); HTTP 402 payments; pay-per-request APIs; EIP-3009 transfer authorization.

How do I install X402 Payments in Claude Code?

Run `npx skills add Nethereum/Nethereum --skill x402-payments -a claude-code`. Or copy the skill folder (plugins/nethereum-skills/skills/x402-payments in Nethereum/Nethereum) into .claude/skills/x402-payments in your project. Claude Code loads it when a task matches its description.

How do I install X402 Payments in Codex?

Run `npx skills add Nethereum/Nethereum --skill x402-payments -a codex`. Or copy the skill folder (plugins/nethereum-skills/skills/x402-payments in Nethereum/Nethereum) into .agents/skills/x402-payments in your project. Codex loads it when a task matches its description.

Can I use X402 Payments in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add Nethereum/Nethereum --skill x402-payments -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/x402-payments, .gemini/skills/x402-payments, .github/skills/x402-payments and .opencode/skills/x402-payments in your project.

What does X402 Payments need to run?

Going by SKILL.md and its folder, X402 Payments needs the command-line tools its instructions call (dotnet).

Does X402 Payments access the network?

SKILL.md names 3 domains. In commands or code: facilitator.x402.org and mainnet.base.org; the agent is likely to contact these when it follows the instructions. As links in the text: docs.nethereum.com. This is read from the text; nothing was executed.

Is X402 Payments safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does X402 Payments use?

X402 Payments is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does X402 Payments use?

About 2.2k tokens (SKILL.md is roughly 8.8k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to X402 Payments?

Skills that share tags, products or a category with X402 Payments: Tsp Csharp (querylenshq/ef-querylens, 225 stars), Alchemy Agentic Gateway (moonpay/skills, 113 stars), Using Dotnet (novotnyllc/dotnet-artisan, 233 stars) and Dotnet Webapi (dotnet/skills, 5.6k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains X402 Payments?

Nethereum (a GitHub organization) maintains it in Nethereum/Nethereum, which has 2,260 GitHub stars. The repository holds 71 skills in this directory. The repository was last updated on October 5, 2026.

Source: Nethereum/Nethereum on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install X402 Payments

Facts

At a glance

What it does

When your agent uses it

Example prompts

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

x402: Crypto Payments (protocol v2)

Client: Pay Automatically

Manual Payment Flow

Server: Protect Endpoints

Self-Facilitated (No External Facilitator)

Asset-Transfer Methods

Permit2 Method

Build EIP-3009 Authorizations Directly

Error Codes (X402ErrorCodes)

Supported Tokens

Files

Compare with similar skills

Similar skills

More from Nethereum/Nethereum

Related

Questions about X402 Payments

Error Codes (`X402ErrorCodes`)