Create a 15-minute HELD reservation. Return a confirmation_token the agent posts to /a2a/confirm to flip to CONFIRMED.
Part of the AdvocateMCP server.
Free to start. No card required.
AI agents use reserve_slot to create or modify resources in AdvocateMCP. 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 reserve_slot 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 AdvocateMCP.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"reserve_slot": {
"limits": [
{
"counter": "reserve_slot_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full AdvocateMCP policy for all 10 tools.
These attack patterns abuse exactly the kind of access reserve_slot 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.
Create a 15-minute HELD reservation. Return a confirmation_token the agent posts to /a2a/confirm to flip to CONFIRMED.. It is categorised as a Write tool in the AdvocateMCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Advocate MCP server in PolicyLayer and add a rule for reserve_slot: 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 AdvocateMCP. Nothing to install.
reserve_slot 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 reserve_slot 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 reserve_slot. 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.
reserve_slot is provided by the Advocate MCP server (https://api.advocatemcp.com/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 10 AdvocateMCP 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.