How to Audit AI Agent Transactions: A Practical Guide to Schema, Spend, and Compliance
Learn how to audit AI agent transactions with a shared audit schema, track spend, and ensure compliance in finance, healthcare, and support use cases.
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Spend Control
Budgets, guardrails, payment risk and reconciliation for agent spend.
Cost per Successful Task: Why Cheap-Per-Token Models Can Be More Expensive
Cost per successful task LLM: why cheap models can end up more expensive. Learn metrics, observability, and spend control strategies.
Audit Schema Implementation Guide: Transaction-Level Agent Auditing with @harpd/agent-transaction-audit-schema
Audit schema implementation guide for transaction-level agent auditing with @harpd/agent-transaction-audit-schema. Learn how to standardize AI agent audit trails, enforce spend control, and ensure compliance.
AI Agent Cost Observability: A Finance Guide to Spend Analytics and Control
AI agent cost observability guide for finance teams – spend analytics, budget tracking, and MCP tool metering
Building a Governance Framework for LLM Agent Spending
Learn how to build a governance framework for LLM agent spending to manage costs effectively and ensure compliance.
How to Implement AI Agent Payment Guardrails: A Practical Guide for SaaS Teams
Learn how to implement AI agent payment guardrails with budget policies, spend caps, and audit trails using open-source tools like x402 and Harpd.
How to Implement Budget Policies for LLM Agents
Learn how to implement budget policies for LLM agents to control costs effectively.
Agent budget control: a copy-paste policy template
A concrete, per-tier budget policy template for agent commerce — what to cap per call, per agent, per endpoint, per day, and how to escalate denials to a human without breaking the agent loop.
When an agent overpaid: three payment risk patterns and the controls that would have stopped them
Three anonymized case studies of agent payment failure patterns — the runaway loop, the wrong-decimals overcharge, and the silent facilitator divergence — and the exact controls that would have stopped each one.
Charging for MCP tools: a paid-tool starter you can ship today
How to turn any MCP tool into a paid tool with x402 — gate tool invocations behind HTTP 402, expose the same MCP schema, and bill per call in USDC. Plus the open-source starter repo that does this end-to-end.
The open-source example project: an agent that pays for its own data
Build self-sustaining AI agents with open-source tools. Tutorial on autonomous data purchase using @harpd/mcp-paid-tool-starter & Harpd Spend Control.
Agent transaction audit: a schema you can copy
An append-only schema for agent payment events that satisfies three auditors at once — finance, security, and compliance — without coupling to any specific payment protocol.
x402 vs Mastercard Agent Pay vs Google AP2: which agent payment protocol should you use?
Compare x402, Mastercard Agent Pay, and Google AP2 payment protocols for your business. Learn about scalability, fees, integration, and security to make an informed decision.
x402 in practice: charge-per-call from zero to first payment
An end-to-end x402 tutorial — set up a paid endpoint with HTTP 402, charge 0.01 USDC per call, observe every payment with the open-source SDK, and verify settlement onchain. No Harpd account required to follow along.