book_hold_slot

SERVERCaboo SOURCEhttps://getcaboo.com/mcp

Medium RISK CLASS

Category Write

Parameters 75 required

Recommended Rate-limitedsee the rule below

Registry record Grade C, identity unverified Pull the record →

This record as markdown: /tools/com-getcaboo-caboo/book-hold-slot.md

WHAT IT DOES

What book_hold_slot does on Caboo

AI agents use book_hold_slot to create or update resources in Caboo, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Caboo environment.

Parameter	Type	Required	Description
`slug`	string	Yes	The provider slug from search_providers or get_provider.
`slotId`	string	Yes	The slotId from book_get_availability the user chose.
`holdLabel`	string	Yes	The exact human-readable booking sentence from the chosen book_get_availability slot's holdLabel. It must describe this slug, serviceKey, and slotId; Caboo reje
`partySize`	integer	—	Number of people, when the user stated one for availability.
`serviceKey`	string	Yes	The service key from book_list_services.
`expiresNote`	string	Yes	Copy this exact value from the chosen availability slot's expiresNote: "held for ~10 minutes". It makes the approval card explain the short hold lifetime before
`idempotencyKey`	string	—	Optional retry key, accepted for forward compatibility. Holds are short-lived; re-holding a taken slot returns slot_already_claimed with alternatives.

Parameters from the server's own tool schema.

RISK

Why book_hold_slot is rated Medium

This tool creates a short-lived reservation hold, which is a reversible write operation — the hold self-expires in ~10 minutes and does not constitute a confirmed booking or financial commitment. It modifies availability state temporarily but is not irreversible (it expires automatically). No money is moved, no data is permanently deleted, and no code is executed.

From the tool's definition Hold one open time slot (a self-expiring reservation, about 10 minutes) and get back a confirmation URL

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs book_hold_slot safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Caboo, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For book_hold_slot, this is the rule to start with:

book_hold_slot Rate-limited

book_hold_slot stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "book_hold_slot": {
      "limits": [
        {
          "counter": "book_hold_slot_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Caboo, apply this rule, and every book_hold_slot call is checked against it from then on.

FAQ

Questions about book_hold_slot

What does the book_hold_slot tool do? +

Hold one open time slot (a self-expiring reservation, about 10 minutes) and get back a confirmation URL. The first argument, holdLabel, must be copied exactly from the chosen book_get_availability slot so the approval card describes the true booking details. Caboo validates holdLabel against slug, serviceKey, and slotId before creating any hold. Give the user ONLY the confirmUrl — Caboo's page collects their contact details and consent; never ask for name, email, or phone in chat. If the slot was just taken, the error includes alternative open times to offer instead. It is categorised as a Write tool in the Caboo MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

What parameters does book_hold_slot accept? +

book_hold_slot accepts 7 parameters: slug, slotId, holdLabel, partySize, serviceKey, expiresNote, idempotencyKey. Required: slug, slotId, holdLabel, serviceKey, expiresNote. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on book_hold_slot? +

Register the Caboo MCP server in PolicyLayer and add a rule for book_hold_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 Caboo. Nothing to install.

What risk level is book_hold_slot? +

book_hold_slot is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit book_hold_slot? +

Yes. Add a rate_limit block to the book_hold_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.

How do I block book_hold_slot completely? +

Set action: deny in the PolicyLayer policy for book_hold_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.

What MCP server provides book_hold_slot? +

book_hold_slot is provided by the Caboo MCP server (https://getcaboo.com/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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