Polar MCP

Polar User Devices

polar_list_user_devices

Read-onlyIdempotent

List devices registered to a Polar user to review connected hardware and registration details. Requires the devices:read permission.

Instructions

List devices registered to the Polar user. Requires devices:read.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`page`	No	Polar page number.
`after`	No	Inclusive start date. Serialized as a Polar date or date-time according to the endpoint contract.
`limit`	No	Local page-size hint used for pagination safety.
`before`	No	Exclusive end date. Serialized as a Polar date or date-time according to the endpoint contract.
`features`	No	Optional Polar v4 feature flags. Values are validated per endpoint; feature ranges that require one day are hydrated safely.
`all_pages`	No	Fetch multiple pages up to max_pages.
`max_pages`	No	Maximum pages to fetch when all_pages is true.
`privacy_mode`	No	Optional per-call privacy override. Defaults to POLAR_PRIVACY_MODE or structured. raw returns upstream Polar 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

TableJSON Schema

Name	Required	Description	Default
`count`	Yes
`records`	Yes
`endpoint`	Yes
`has_more`	Yes
`next_page`	No
`privacy_mode`	Yes
`pages_fetched`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed7 schema fields changedv0.5.4Oct 4, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

changedInput schema / properties / after / description

Previous value: -"Only return Polar records after this time. Converted to Polar's inclusive from query parameter."New value: +"Inclusive start date. Serialized as a Polar date or date-time according to the endpoint contract."

changedInput schema / properties / before / description

Previous value: -"Only return Polar records before this time. Converted to Polar's exclusive to query parameter."New value: +"Exclusive end date. Serialized as a Polar date or date-time according to the endpoint contract."

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"
+}

addedInput schema / properties / features

Added value: +{
+  "description": "Optional Polar v4 feature flags. Values are validated per endpoint; feature ranges that require one day are hydrated safely.",
+  "items": {
+    "minLength": 1,
+    "type": "string"
+  },
+  "type": "array"
+}

changedInput schema / properties / privacy_mode / description

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

changedOutput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

First observedv0.3.6Jul 9, 2026

TDQS

A3.9/5.0

Behavior4/5

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

Annotations already declare readOnly, idempotent, non-destructive, and open-world, so the safety profile is covered. The description adds the concrete auth scope requirement ('Requires devices:read'), which is not derivable from the annotations. It doesn't mention pagination semantics or the privacy_mode escalation behavior, keeping it below 5.

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?

Two short sentences, front-loaded with the purpose and followed by the auth requirement. Every sentence earns its place with zero filler.

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?

For a read-only list tool with a rich 10-parameter schema, full annotations, and an output schema, the description is sufficient at minimum. However, it omits the pagination model (page/limit/all_pages) and the privacy_mode/explicit_user_intent escalation contract, which are non-trivial behaviors an agent should grasp before calling.

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 90%, so the schema itself already documents page, after, before, limit, features, all_pages, max_pages, privacy_mode, and explicit_user_intent well. The description adds no additional parameter meaning, so baseline 3 applies.

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?

States a specific verb ('List') and resource ('devices registered to the Polar user'), which cleanly distinguishes it from the many sibling list_* tools (activity, sleep, sports, etc.). No ambiguity about what is returned at a high level.

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 implies usage via the scope line ('devices registered to the Polar user') and the auth requirement, but it never states when to prefer this over siblings or any preconditions beyond the scope. Adequate but with clear gaps for an agent navigating 35+ sibling tools.

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

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