mcp-server-linear

update_issue_labels

Update labels on a Linear issue to categorize or reclassify it. Provide the issue ID and new label names.

Instructions

Update the labels of an existing issue in Linear

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": {
      "issueId": "<issueId>"
    },
    "name": "update_issue_labels"
  }
}

Input Schema

Name	Required	Description	Default
`labels`	No	issue labels
`issueId`	Yes	target issue id

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.15Jun 26, 2026

TDQS

B3.4/5.0

Behavior2/5

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

No annotations are provided, and the description does not disclose whether labels are replaced or appended, validation rules, permissions, or any side effects. This 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.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single sentence conveying the core purpose without unnecessary words. Efficient but could be slightly more structured with front-loaded key details.

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?

Given the tool's simplicity and full schema coverage, the description is adequate but lacks behavioral nuances essential for correct agent selection and invocation.

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 schema already describes both parameters. The description adds no additional meaning beyond the schema, but being at baseline 3 is appropriate.

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 clearly states the verb 'Update', the resource 'labels of an existing issue', and the context 'Linear'. This distinguishes it from sibling tools like 'update_issue' which deals with other fields.

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?

No explicit when-to-use or alternative guidance is provided. While it implies label-specific updates, it does not clarify when to use this vs. 'update_issue' or other field-specific tools.

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