Return the x402 payment challenge needed to top up credits for an existing agent endpoint. Accepts either a dashboard PAT with mcp:endpoints:write or mcp:* or a legacy endpoint API key.
Risk signalsHandles credentials or secrets (apiKey)
Part of the Singularity Layer MCP server.
Free to start. No card required.
AI agents use request_endpoint_topup_payment to create or modify resources in Singularity Layer MCP. 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 request_endpoint_topup_payment 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 Singularity Layer MCP.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"request_endpoint_topup_payment": {
"limits": [
{
"counter": "request_endpoint_topup_payment_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Singularity Layer MCP policy for all 38 tools.
These attack patterns abuse exactly the kind of access request_endpoint_topup_payment 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.
Return the x402 payment challenge needed to top up credits for an existing agent endpoint. Accepts either a dashboard PAT with mcp:endpoints:write or mcp:* or a legacy endpoint API key.. It is categorised as a Write tool in the Singularity Layer MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Singularity Layer MCP server in PolicyLayer and add a rule for request_endpoint_topup_payment: 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 Singularity Layer MCP. Nothing to install.
request_endpoint_topup_payment 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 request_endpoint_topup_payment 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 request_endpoint_topup_payment. 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.
request_endpoint_topup_payment is provided by the Singularity Layer MCP server (https://mcp.x402layer.cc/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 38 Singularity Layer MCP 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.