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Adds mcpc x402 subcommands: init, import, list, remove, sign. Wallets stored in ~/.mcpc/wallets.json. Signing parses PAYMENT-REQUIRED headers and produces PAYMENT-SIGNATURE for x402 payment protocol.
Implement automatic x402 payment signing when calling paid MCP tools. The --x402 global flag enables auto-payment using the default wallet. Architecture: - Shared signer module (src/lib/x402/signer.ts) for EIP-3009 typed data signing - Fetch middleware (src/lib/x402/fetch-middleware.ts) wraps SDK's fetch with: - Proactive signing: reads _meta.x402 from cached tools list, signs before request - 402 fallback: if server returns HTTP 402, parses PAYMENT-REQUIRED header, signs, retries once - Bridge receives wallet credentials via IPC (set-x402-wallet message type) - Bridge maintains its own tools cache for proactive signing (populated on connect, updated via listChanged notifications) - Direct connections (withMcpClient) only support 402 fallback (no persistent tools cache) - customFetch option threaded through transports.ts -> factory.ts -> SDK transport Known issues and TODOs: - --x402 is currently a boolean flag (always uses 'default' wallet). Supporting --x402 [wallet-name] with optional value is blocked by Commander.js not being able to disambiguate optional option values from subcommands. Options considered: (a) pre-process args to convert '--x402 name' to '--x402=name' before Commander, (b) use separate --x402-wallet <name> option, (c) strip --x402 from Commander args and re-inject via closure. All approaches were prototyped but add significant complexity. For now --x402 uses the default wallet; named wallets can wait. - No unit tests yet for signer.ts and fetch-middleware.ts - No E2E test with the demo x402 server - Interactive shell does not support --x402 (only direct commands and sessions) - Direct connections don't have proactive signing (no tools cache), only 402 fallback - Pre-existing flaky test: sessions/bridge-resilience occasionally fails (unrelated)
Drop multi-wallet support (named wallets, --name options, defaultWallet)
in favor of a single wallet stored in ~/.mcpc/wallets.json with a
versioned format { version: 1, wallet?: WalletData }.
- Remove wallet names from WalletData, X402WalletCredentials, SessionData
- Replace SessionData.walletName with x402 boolean flag
- Simplify wallets.ts CRUD to operate on single wallet
- Rename 'list' command to 'info', remove --name from all x402 commands
- Update bridge IPC: --wallet <name> arg becomes --x402 boolean flag
- Update all callsites (bridge-manager, sessions, helpers, parser, CLI)
This avoids Commander.js optional-arg parsing complexity for --x402
[wallet-name] and matches the actual use case (one wallet per user).
Multi-wallet can be added later with --x402-wallet <name> if needed.
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Summary
Add x402 payment protocol support — automatic USDC payments for paid MCP tools on Base/Base Sepolia.
mcpc x402 init|import|info|remove|signfor wallet management--x402flag enables auto-payment on both direct and session connections_meta.x402from tools list) and 402 fallback (retry on HTTP 402)~/.mcpc/wallets.json(versioned format,0600perms)viemfor EIP-3009 signing, customfetchwrapper via SDK transportTested e2e against local x402 demo server (direct + bridge, paid + free tools). All existing tests pass except pre-existing flaky
bridge-resilience(parallel test pollution causes INVARIANT VIOLATION — unrelated to x402).