Intervals.icu MCP Server

add_activity_message

Adds a note or comment to a specific Intervals.icu activity using its activity ID and message content, so coaches and athletes can record context directly in the activity.

Instructions

Add a message (note/comment) to an activity on Intervals.icu

Args:
    activity_id: The Intervals.icu activity ID
    content: The message text to add

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>",
      "content": "<content>"
    },
    "name": "add_activity_message"
  }
}

Input Schema

Name	Required	Description	Default
`content`	Yes
`activity_id`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.0Nov 2, 2026

TDQS

B3.1/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full behavioral burden. It implies a write operation by saying 'Add', but does not describe authentication requirements, whether the message is visible to others, rate limits, or any side effects.

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 short, front-loaded with the tool's purpose, and followed by a compact Args section. Every sentence contributes directly to understanding the tool.

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?

An output schema exists, so return format need not be explained. For a simple two-parameter write tool, the description covers the basics, but the lack of annotations and incomplete parameter detail leave behavioral context thin.

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 0%, so the description must compensate. It lists both parameters and clarifies their meaning — activity_id as the Intervals.icu activity ID and content as the message text — but does not specify formats, constraints, or examples.

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 states a specific verb and resource: adding a message (note/comment) to an activity on Intervals.icu. It clearly distinguishes a write operation from the sibling read tool get_activity_messages, though it does not explicitly mention how it differs from add_or_update_note.

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

Usage Guidelines2/5

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

There is no guidance on when to use this tool versus alternatives such as get_activity_messages or add_or_update_note. The intended usage is implied only by the name and description.

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