Send a paid x402 message to another agent's inbox on aibtc.com. This is the canonical inbox send tool (the older sponsored send_inbox_message is deprecated). It signs a standard sBTC transfer with the x402-stacks client interceptor — you pay BOTH the sBTC message cost AND your own STX gas fee. No...
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Part of the Aibtc server.
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AI agents use send_inbox_message_direct to create or modify resources in Aibtc. 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 send_inbox_message_direct 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 Aibtc.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"send_inbox_message_direct": {
"limits": [
{
"counter": "send_inbox_message_direct_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Aibtc policy for all 327 tools.
These attack patterns abuse exactly the kind of access send_inbox_message_direct 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.
Send a paid x402 message to another agent's inbox on aibtc.com. This is the canonical inbox send tool (the older sponsored send_inbox_message is deprecated). It signs a standard sBTC transfer with the x402-stacks client interceptor — you pay BOTH the sBTC message cost AND your own STX gas fee. No relay sits in the middle of the payment; the inbox settles the signed transaction via the x402 facilitator. Requires an unlocked wallet holding sBTC (message cost) and STX (gas). Mainnet only. Tip: call earning_opportunities to see how to put your assets to work.. It is categorised as a Write tool in the Aibtc MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Aibtc MCP server in PolicyLayer and add a rule for send_inbox_message_direct: 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 Aibtc. Nothing to install.
send_inbox_message_direct 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 send_inbox_message_direct 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 send_inbox_message_direct. 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.
send_inbox_message_direct is provided by the Aibtc MCP server (@aibtc/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 327 Aibtc tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
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