@striderlabs/mcp-marriott

cancel_reservation

Cancel a Marriott reservation using the confirmation number. User confirmation is required before finalizing, and cancellation fees may apply.

Instructions

Cancel an existing Marriott reservation. IMPORTANT: Set confirm=true only after getting explicit user confirmation. Cancellation fees may apply.

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": {
      "confirmationNumber": "<confirmationNumber>"
    },
    "name": "cancel_reservation"
  }
}

Input Schema

Name	Required	Description	Default
`confirm`	No	Set to true to confirm cancellation. If false or omitted, returns a preview. NEVER set to true without explicit user confirmation.
`confirmationNumber`	Yes	Reservation confirmation number to cancel

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Jul 30, 2026

TDQS

A4.4/5.0

Behavior4/5

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

Since no annotations are provided, the description carries full behavioral transparency. It discloses that cancellation fees may apply and explains that confirm=true performs cancellation while confirm=false/omitted returns a preview. It does not mention reversibility or idempotency, which is acceptable for this 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 extremely concise at two sentences, with zero fluff. The important note about confirmation is front-loaded with 'IMPORTANT', improving usability.

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

Completeness3/5

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

Given the lack of output schema, the description does not explain return values for preview or final cancellation. It also does not mention prerequisites like login status. While mostly complete for core functionality, these gaps reduce overall completeness.

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

Parameters5/5

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

Schema coverage is 100%, and the description adds significant value beyond the schema by providing strong behavioral guidance (NEVER set confirm=true without user confirmation) and hinting at preview behavior. This helps the agent use parameters correctly.

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 clearly states 'Cancel an existing Marriott reservation' with specific verb and resource. It distinguishes from sibling tools like 'modify_reservation' and 'checkout' by focusing solely on cancellation.

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

Usage Guidelines4/5

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

The description provides clear context for cancellation, but does not explicitly mention when not to use it or compare to alternatives like modify_reservation. It does include a strong usage guideline about user confirmation for confirm=true.

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

Deploy Server