Spotinst MCP Server

by arnstarn

Overview Schema Source Related Servers Discussions Admin

Python

Remote

detach_instances

Detach and optionally terminate EC2 instances from an AWS Ocean cluster. Requires confirmation to execute.

Instructions

DESTRUCTIVE: Detach and optionally terminate instances from an AWS Ocean cluster. Requires confirm=true.

Args: cluster_id: The Ocean cluster ID (e.g. o-abc12345) instance_ids: Comma-separated EC2 instance IDs (e.g. i-abc123,i-def456) confirm: Must be true to execute. Safety guard. should_terminate: Terminate instances after detach (default: true) should_decrement_capacity: Reduce target capacity (default: true) account_id: Optional account ID. Defaults to SPOTINST_ACCOUNT_ID env var.

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": {
      "cluster_id": "<cluster_id>",
      "instance_ids": "<instance_ids>"
    },
    "name": "detach_instances"
  }
}

Input Schema

Name	Required	Description	Default
`cluster_id`	Yes
`instance_ids`	Yes
`confirm`	No
`should_terminate`	No
`should_decrement_capacity`	No
`account_id`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Mar 21, 2026

TDQS

A4/5.0

Behavior4/5

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

With no annotations, the description carries full burden. It discloses destructive behavior, requires confirmation, and explains defaults for termination and capacity decrement. It lacks details on error handling or side effects beyond termination.

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

Conciseness4/5

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

The description is well-structured with a bold header and bullet-pointed arguments, making it easy to scan. It could be slightly more concise by removing redundant phrasing like 'DESTRUCTIVE' repeated in context.

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

Completeness4/5

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

Given the complexity of 6 parameters and destructive nature, the description covers purpose, parameters, and safety. It does not address error conditions or prerequisites, but the output schema is present so return values are not required.

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 0%, so description must add meaning. It thoroughly explains each parameter: cluster_id, instance_ids (comma-separated), confirm (must be true), should_terminate (default true), should_decrement_capacity (default true), and account_id (optional, env var default). This provides significant value beyond the schema.

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

Purpose4/5

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

The description clearly states it detaches and optionally terminates instances from an AWS Ocean cluster, specifying the verb and resource. It distinguishes from siblings by using 'Ocean cluster' context, but does not explicitly differentiate from 'remove_instances' which may be similar.

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

Usage Guidelines3/5

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

The description highlights the destructive nature and the requirement for confirm=true as a safety guard, implying caution. However, it does not provide explicit guidance on when to use this tool versus alternatives like 'remove_instances' or when not to use it.

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