Redeem Cashu ecash tokens directly on a toll-booth server, avoiding the Lightning round-trip. Handles the two-step flow automatically (create invoice then redeem token). Only works with toll-booth servers.
Risk signalsAccepts URL/endpoint input (url) · Handles credentials or secrets (token)
Part of the 402 server.
Free to start. No card required.
AI agents use l402-redeem-cashu to create or modify resources in 402. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call l402-redeem-cashu repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach 402.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"l402-redeem-cashu": {
"limits": [
{
"counter": "l402-redeem-cashu_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full 402 policy for all 11 tools.
These attack patterns abuse exactly the kind of access l402-redeem-cashu gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Redeem Cashu ecash tokens directly on a toll-booth server, avoiding the Lightning round-trip. Handles the two-step flow automatically (create invoice then redeem token). Only works with toll-booth servers.. It is categorised as a Write tool in the 402 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the 402 MCP server in PolicyLayer and add a rule for l402-redeem-cashu: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches 402. Nothing to install.
l402-redeem-cashu is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the l402-redeem-cashu rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for l402-redeem-cashu. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
l402-redeem-cashu is provided by the 402 MCP server (402-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 11 402 tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.