Fitbit MCP

List Fitbit Devices

fitbit_list_devices

Read-onlyIdempotent

List devices connected to your Fitbit account. Use this to identify which trackers or smartwatches are linked and to attribute health data to the correct device.

Instructions

List devices connected to the authenticated Fitbit account. Requires settings scope.

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": "fitbit_list_devices"
  }
}

Input Schema

Name	Required	Description	Default
`privacy_mode`	No	Optional per-call privacy override. Defaults to FITBIT_PRIVACY_MODE or structured. raw returns upstream Fitbit JSON. summary removes GPS/map details.
`response_format`	No		markdown
`explicit_user_intent`	No	Required true when privacy_mode=raw or include_gps=true (agent escalation of redaction).

Output Schema

Name	Required	Description	Default
`data`	Yes
`endpoint`	Yes
`privacy_mode`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv0.4.11Jul 30, 2026

addedInput schema / properties / explicit_user_intent

Added value: +{
+  "description": "Required true when privacy_mode=raw or include_gps=true (agent escalation of redaction).",
+  "type": "boolean"
+}

changedInput schema / properties / privacy_mode / description

Previous value: -"Optional per-call privacy override. Defaults to FITBIT_PRIVACY_MODE or structured. raw returns upstream Fitbit JSON. summary minimizes sensitive health and profile details."New value: +"Optional per-call privacy override. Defaults to FITBIT_PRIVACY_MODE or structured. raw returns upstream Fitbit JSON. summary removes GPS/map details."

First observedv0.4.5May 26, 2026

TDQS

A4/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive nature. The description adds the authorization context ('settings scope'), which goes beyond annotations. No additional behavioral traits (e.g., return format) are described, but annotations cover safety well.

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 wasted words. It is front-loaded with the main purpose and efficiently states the requirement.

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 presence of an output schema and the simple nature of listing devices, the description is fairly complete. It lacks mention of potential nuances like pagination or device types, but these are likely handled by schema/output schema.

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 67% (2 out of 3 parameters have descriptions). The description does not add any parameter meaning beyond the schema; it remains at the baseline for moderate coverage.

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 explicitly states 'List devices connected to the authenticated Fitbit account,' which clearly identifies the action (list) and resource (devices). It distinguishes from sibling tools like fitbit_list_activities or fitbit_list_sleep, which target different data types.

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 mentions a prerequisite ('Requires settings scope'), but does not specify when to use this tool versus alternatives or provide any exclusions. Usage is implied but not explicitly guided.

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