GoHighLevel MCP

ghl_create_block_slot

Block a time slot on a calendar to prevent bookings during that period. Manage availability in GoHighLevel.

Instructions

Block a time slot on a calendar (prevents bookings during that period).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "calendarId": "<calendarId>",
      "startTime": "<startTime>",
      "endTime": "<endTime>"
    },
    "name": "ghl_create_block_slot"
  }
}

Input Schema

Name	Required	Description
`title`	No
`endTime`	Yes	ISO 8601 end time
`startTime`	Yes	ISO 8601 start time
`calendarId`	Yes
`assignedUserId`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.4Aug 2, 2026

TDQS

B3.1/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full responsibility for disclosing behavior. It only mentions that blocking prevents bookings, but does not discuss side effects, permissions, reversibility, or what the response will be; this is insufficient for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence with no filler, directly stating the action and its purpose. It is well-structured and front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool has 5 parameters, 3 required, no annotations, and no output schema. The description is too sparse to fully explain the tool's behavior and parameters, especially given the weak schema coverage. It leaves the agent with insufficient context to invoke it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description does not mention any parameters or add meaning beyond the input schema. Schema coverage is only 40% (only startTime and endTime have descriptions), leaving calendarId, title, and assignedUserId unexplained in both the schema and the description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb 'block' and clearly identifies the resource as 'a time slot on a calendar.' It also explains the effect ('prevents bookings during that period'), which distinguishes it from appointment creation or event deletion tools in the sibling list.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like ghl_create_appointment or ghl_get_free_slots. There is no mention of appropriate scenarios, prerequisites, or exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server