Scope the reused x402 payment signature to tools the server charges for - #368
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Follow-up to #365, which made the challenge-signed payment reach the retry by checking the cache before the tool metadata gate. That also attached the session signature to every tools/call, including free tools, handing a live authorization to calls that never asked for one. The cache now records which tools the server actually charged for (a payment-required tool result, or an HTTP 402 on a tools/call), and the signature is reused only for those. Session-level reuse across paid calls is unchanged — mcp.apify.com treats the signature as a prepaid token (#247). Also adds the CHANGELOG entry the fix was missing. Refs #365, #343, #247 Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01YFNAoYc88jVSqaj86VdTUJ
epistemedeus
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Aug 11, 2026
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Reviewed the result-challenge and HTTP 402 paths. The paymentRequiredTools scope closes cached-authorization spillover to free and unknown tools without reintroducing the retry failure from #365. The new tests cover those boundaries and preserve the documented prepaid-session reuse behavior. Looks good.
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Follow-up to #365 (thanks @epistemedeus — the diagnosis there was right and the fix is correct). Checking the cache before the tool-metadata gate also means the session's payment signature is now attached to every
tools/call, including free tools, handing a live authorization to calls that never asked for one. The cache now records which tools the server actually charged for, and reuses the signature only for those.X402PaymentCache.paymentRequiredToolsrecords a tool on a payment-required tool result (bridge) or an HTTP 402 on atools/call(middleware)_meta.x402or a previous charge; proactive signing still requires_meta.x402Refs #365, #343, #247
https://claude.ai/code/session_01YFNAoYc88jVSqaj86VdTUJ
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