Nightscout MCP Server

insulin_sensitivity_check

Compare actual insulin sensitivity factor with profile settings to identify needed adjustments, using correction bolus and glucose data from at least 3 days.

Instructions

Analyze real-world insulin sensitivity by tracking correction boluses and their glucose impact. Compares actual ISF from data with profile ISF to detect if settings need adjustment. Requires at least 3 days with correction events.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "insulin_sensitivity_check"
  }
}

Input Schema

Name	Required	Description	Default
`days`	No	Days to analyze (default 7)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.4.0Sep 6, 2026

TDQS

A3.9/5.0

Behavior3/5

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

No annotations are provided, so the description carries the full burden. It discloses the analytical behavior and data requirement, but does not explicitly state that the tool is read-only or describe what the output looks like. The wording implies a diagnostic check, yet an agent might still wonder whether the tool modifies settings.

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?

Three tight sentences that front-load the purpose, then explain the comparison logic, and end with the key prerequisite. Every sentence earns its place with no redundant or vague wording.

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?

With no output schema and no annotations, the description should clarify the return value and safety profile. It covers the core purpose and constraint, but an agent is left without explicit information on what the tool returns (e.g., a recommendation, numeric values) or whether it is purely read-only, so completeness is moderate.

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

Parameters3/5

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

Schema description coverage is 100%, with the only parameter 'days' already documenting range and default. The description adds no additional parameter-level meaning beyond reaffirming the 3-day minimum, so the baseline score of 3 is appropriate.

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 specific verbs ('Analyze', 'Compares') and identifies the resource (real-world insulin sensitivity) and method (tracking correction boluses, comparing actual ISF with profile ISF). This clearly distinguishes it from siblings like carb_ratio_check or get_statistics, making the tool's purpose unambiguous.

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?

Provides a clear prerequisite ('Requires at least 3 days with correction events') and an implied use case (detecting if ISF settings need adjustment). However, it does not explicitly name alternative tools or state when not to use this tool, so it falls short of full routing guidance.

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