Assign a Linear issue to a specific user by issue ID and assignee ID, or unassign by passing null.
Assign an issue to a user
| Name | Required | Description | Default |
|---|---|---|---|
| issueId | Yes | ID or identifier of the issue to assign (e.g., ABC-123) | |
| assigneeId | Yes | ID of the user to assign the issue to, or null to unassign |
| Name | Required | Description | Default |
|---|---|---|---|
| issue | No | ||
| success | No |
Changes observed during successful MCP inspections.
v1.4.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false, and idempotentHint=true, covering the mutation and idempotency aspects. The description adds no extra behavioral context, such as that assignment overrides the current assignee or any side effects. It does not contradict the annotations, but it also does not go beyond them, so a 3 is appropriate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single, direct sentence with no wasted words. It is front-loaded with the action and objects, making it easy to parse quickly.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple two-parameter action, the description provides the essential purpose, and the schema handles parameter details. However, it omits any mention of prerequisites (e.g., issue existence, user membership) or the fact that it replaces the current assignee. Since an output schema exists, this is not fully inadequate but leaves some gaps.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema covers 100% of the parameters with clear descriptions, including the null option for unassigning. The description adds no additional meaning beyond what is already in the schema. Baseline 3 is assigned since the schema does the heavy lifting.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a clear action (assign), the resource (issue), and the target (user). It is specific and not a tautology. However, it does not explicitly differentiate from sibling tools like linear_updateIssue, which might also change assignment, so it loses a point for lacking that discrimination.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
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 vs. alternatives. The description does not mention that this is the dedicated tool for assignment or that other tools (e.g., linear_updateIssue) should be used for other issue modifications. It leaves the selection entirely to the agent's inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.