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Documentation Index

Fetch the complete documentation index at: https://agentcash.dev/docs/llms.txt

Use this file to discover all available pages before exploring further.

The primary use case for AgentCash is calling APIs that require payment. Endpoints may charge via x402 (on-chain USDC transfer) or MPP (signed off-chain payment intent); AgentCash handles both transparently. This guide covers the flow from your agent’s perspective.

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Basic usage

Ask your agent to fetch data from a premium endpoint:
Use AgentCash to fetch https://stableenrich.dev/api/company/lookup with body {"domain": "anthropic.com"}.
The agent calls the fetch tool (in MCP mode) or uses the CLI, which:
  1. Sends the request to the endpoint
  2. Receives a 402 Payment Required response listing accepted protocols (x402, mpp) and networks
  3. Picks a protocol your wallet supports and signs the payment proof
  4. Retries the request with the proof attached
  5. Returns the response data and payment info

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Checking the price first

If you want to know the cost before paying, ask your agent to check the endpoint:
Check the pricing for https://stableenrich.dev/api/company/lookup using AgentCash.
This probes the endpoint without making a payment. It returns the price, accepted methods, and input/output schema.

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Request options

The fetch command accepts standard HTTP options: 
URL:     https://example.com/api/endpoint
Method:  POST (default: GET)
Headers: {"Content-Type": "application/json"}
Body:    {"key": "value"}
Timeout: 30000 (milliseconds)
AgentCash sets Content-Type: application/json by default for requests with a body.

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Payment info in responses

Every paid request returns payment metadata alongside the response data:
  • amount: USDC paid
  • transaction: on-chain transaction hash
  • network: which chain the payment was made on

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Error handling

If a payment fails, AgentCash returns a clear error. Common issues:
ErrorCauseFix
Insufficient balanceNot enough USDC for the request priceFund your wallet
Payment verification failedOn-chain verification issueRetry the request
TimeoutEndpoint took too long to respondIncrease timeout or try again