Intervals.icu MCP Server

get_activity_intervals

Retrieve interval-level performance data for an activity, including power, heart rate, cadence, speed, and environmental metrics, plus grouped intervals.

Instructions

Get interval data for a specific activity from Intervals.icu

This endpoint returns detailed metrics for each interval in an activity, including power, heart rate, cadence, speed, and environmental data. It also includes grouped intervals if applicable.

Args: activity_id: The Intervals.icu activity ID api_key: The Intervals.icu API key (optional, will use API_KEY from .env if not provided)

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": {
      "activity_id": "<activity_id>"
    },
    "name": "get_activity_intervals"
  }
}

Input Schema

Name	Required	Description	Default
`api_key`	No
`activity_id`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 6, 2026

TDQS

A4.3/5.0

Behavior4/5

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

With no annotations provided, the description carries the behavioral disclosure burden. It discloses what the endpoint returns (power, heart rate, cadence, speed, environmental data, grouped intervals) and the API-key fallback behavior, which is useful for correct invocation. It does not cover rate limits or error behavior, but these are less critical for a read-only retrieval 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 compact and front-loaded with the primary purpose, then gives return details and parameter guidance without repetition. Every sentence contributes meaningful invocation information.

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?

For a two-parameter retrieval tool with an output schema, the description covers purpose, parameter meaning, auth behavior, and the shape of returned data. It could be slightly more complete by stating explicit usage boundaries versus sibling activity endpoints, but nothing critical is missing for invoking it correctly.

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?

Input schema has 0% description coverage, but the Args section documents both parameters: activity_id is identified as the Intervals.icu activity ID and api_key is explained as optional with a .env fallback. This fully compensates for the empty schema property descriptions.

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 opening sentence names a specific action ('Get') and a distinct resource ('interval data for a specific activity'), which separates it from sibling tools like get_activity_streams or get_activity_raw. The following sentence reinforces the scope by listing the interval-level metrics returned.

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 conveys that the tool is for retrieving interval-level metrics and grouped intervals, so an agent can infer appropriate use. However, it does not explicitly state when to prefer this over alternatives or mention exclusions, leaving selection mostly to inference.

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