Linear MCP Server

linear_create_project_milestone

Create a new project milestone by providing project ID, name, and optional details like description, target date, and sort order.

Instructions

Create a new project milestone

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": {
      "projectId": "<projectId>",
      "name": "<name>"
    },
    "name": "linear_create_project_milestone"
  }
}

Input Schema

Name	Required	Description
`projectId`	Yes	Project ID to create milestone for
`name`	Yes	Milestone name
`description`	No	Milestone description
`targetDate`	No	Target completion date (ISO format)
`sortOrder`	No	Sort order for the milestone

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.6.0Jun 20, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It only states 'create' without revealing side effects, idempotency, or error conditions, which is insufficient for a mutation 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 a single, clear sentence with no unnecessary words. It is front-loaded with the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has 5 parameters and no output schema, the description is very brief. It omits important context about how milestones relate to projects, default behavior, and return value. A more complete description would include expected outcomes or usage hints.

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 coverage is 100%, so the description does not need to explain parameters further. However, it adds no additional semantic value beyond the schema descriptions.

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 clearly states the action (create) and the resource (project milestone), distinguishing it from sibling tools like update and delete. However, it lacks context on what a project milestone represents in Linear.

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?

No guidance is provided on when to use this tool versus alternatives, or any prerequisites (e.g., existing project). The description offers no context for appropriate usage.

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