Record a completed spend with optional outcome tracking. Call this AFTER paying for a service to track spending and build ROI history.
Part of the Zero Core Budget server.
Free to start. No card required.
AI agents invoke report_spend to trigger processes or run actions in Zero Core Budget. Execute operations can have side effects beyond the immediate call -- triggering builds, sending notifications, or starting workflows. Rate limits and argument validation are essential to prevent runaway execution.
report_spend can trigger processes with real-world consequences. An uncontrolled agent might start dozens of builds, send mass notifications, or kick off expensive compute jobs. PolicyLayer enforces rate limits and validates arguments to keep execution within safe bounds.
Execute tools trigger processes. Rate-limit and validate arguments to prevent unintended side effects.
{
"version": "1",
"default": "deny",
"tools": {
"report_spend": {
"limits": [
{
"counter": "report_spend_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}See the full Zero Core Budget policy for all 6 tools.
These attack patterns abuse exactly the kind of access report_spend gives an agent. Each links to the full case and the policy that stops it:
Other execute tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Record a completed spend with optional outcome tracking. Call this AFTER paying for a service to track spending and build ROI history.. It is categorised as a Execute tool in the Zero Core Budget MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Zero Core Budget MCP server in PolicyLayer and add a rule for report_spend: 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 Zero Core Budget. Nothing to install.
report_spend is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the report_spend 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 report_spend. 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.
report_spend is provided by the Zero Core Budget MCP server (@meltingpixels/zero-core-budget). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 6 Zero Core Budget 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.