Add paid HTTP client command

[ai-virtual-b]

Summary

• Add acp http <url> as a generic HTTP caller for agents, separate from ACP job lifecycle commands.
• Default behavior is query-only: it sends one HTTP request and surfaces the response, including any 402 Payment Required.
• Add --pay to explicitly opt into paying supported x402/MPP challenges with the active ACP agent wallet and retrying the request.
• Support --protocol auto|x402|mpp, custom methods/headers, raw/file/JSON request bodies, response headers, output files, and JSON output.
• Use official x402 client primitives for x402 typed-data payment payloads and official mppx client primitives for MPP Tempo push-mode credentials.

CLI Workflow

1. Query an endpoint without paying

acp http https://api.example.com/paid-resource

This makes a single request. If the endpoint is paid, the CLI returns the 402 response to the agent. No wallet signing, payment submission, retry, or saved payment state happens.

For JSON POST:

acp http -X POST --json-body '{"prompt":"hello"}' https://api.example.com/jobs

2. Decide whether to pay

The agent inspects the 402 response from step 1 and decides whether the price/protocol is acceptable.

If the agent decides not to pay, the workflow stops after step 1.

3. Pay and retry explicitly

acp http --pay https://api.example.com/paid-resource

This is a new CLI invocation. It does not reuse hidden state from the query command.

Internal flow for this --pay command:

1. CLI sends the request.
2. Endpoint returns a fresh 402 with x402 or MPP challenge details.
3. CLI parses the challenge.
4. CLI uses the active ACP agent wallet/signer to create the protocol payment credential.
5. CLI retries the same request with the payment header.
6. Endpoint returns the paid response.

For JSON POST:

acp http --pay -X POST --json-body '{"prompt":"hello"}' https://api.example.com/jobs

4. Force a protocol when the agent already knows it

acp http --protocol x402 https://api.example.com/x402-endpoint
acp http --protocol mpp https://api.example.com/mpp-endpoint

To pay:

acp http --pay --protocol x402 https://api.example.com/x402-endpoint
acp http --pay --protocol mpp https://api.example.com/mpp-endpoint

--protocol auto is the default. In query mode, auto/MPP requests include Accept-Payment: tempo/charge so MPP endpoints can return useful challenge details, but the CLI still does not pay unless --pay is present.

Payment Details

• x402: parses x402 payment requirements from the 402, creates a payment payload through the x402 client, signs EIP-712 typed data using the active ACP agent wallet signer, then retries with the x402 payment header.
• MPP: parses the MPP WWW-Authenticate: Payment ... challenge, creates an MPP credential through mppx, uses ACP wallet adapter calls for Tempo push-mode payment, then retries with the MPP Authorization credential.
• No separate wallet/private key/SDK install is required for the caller beyond the configured ACP CLI agent wallet.

Tests

• npx tsc --noEmit
• npm run acp -- http --help
• No-pay non-402 POST smoke test: request count = 1
• No-pay 402 smoke test: returns status 402, request count = 1, no retry
• --json HTTP 500 smoke test: exits with code 1

Notes

• This PR does not fully prove live x402/MPP settlement end-to-end; that still requires funded wallets, supported chains, and real paid endpoints.
• npm run build may fail in this local sandbox because TypeScript cannot create dist; npx tsc --noEmit passes.

[ai-virtual-b]

Bugbot follow-up fixes pushed in 41efadb:

• Cached MPP viem client instances per chain so sendCalls/getCallsStatus share sentCalls state.
• Reworked auto mode to reuse the first 402 response for x402/MPP credential creation instead of invoking wrappers that issue another unpaid probe.

Validation after the change:

• npx tsc --noEmit
• npm run acp -- http --help
• local non-402 POST smoke test confirmed request count remains 1
• local --json HTTP 500 smoke test exits with code 1

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[ai-virtual-b]

Latest Bugbot finding fixed in 8902193:

• Auto-mode probes now include Accept-Payment: tempo/charge so MPP servers can return the same challenge shape as explicit --protocol mpp.
• The first 402 response is still reused, so this does not reintroduce the duplicate unpaid probe.

Validation:

• npx tsc --noEmit
• npm run acp -- http --help
• local auto-mode POST smoke test confirmed request count = 1 and Accept-Payment = tempo/charge
• local --json HTTP 500 smoke test exits with code 1

[ai-virtual-b]

Updated the CLI semantics in 4dc2124:

• acp http <url> now makes a single query request and surfaces the response, including 402 challenges. It does not sign/pay/retry.
• acp http --pay <url> opts into signing/paying supported x402/MPP challenges with the active agent wallet and retrying.
• Query mode still sends Accept-Payment: tempo/charge for auto/MPP discovery so MPP endpoints can return useful 402 challenge details.

Validation:

• npx tsc --noEmit
• npm run acp -- http --help
• no-pay non-402 POST: request count = 1
• no-pay 402: returned status 402, request count = 1, no retry
• JSON HTTP 500 still exits with code 1