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add_user_to_group

Adds a specified Microsoft 365 user to a group and grants access to group-connected SharePoint sites. Use it to manage group membership and permissions.

Instructions

Add a user to a group (also grants access to group-connected SharePoint sites)

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": {
      "user_id": "<user_id>",
      "group_id": "<group_id>"
    },
    "name": "add_user_to_group"
  }
}

Input Schema

Name	Required	Description	Default
`user_id`	Yes	The user ID or user principal name
`group_id`	Yes	The group ID

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Nov 2, 2026

TDQS

B3.3/5.0

Behavior3/5

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

With no annotations, the description carries the full burden, and it does disclose one meaningful side effect: the addition also grants access to group-connected SharePoint sites. However, it says nothing about required permissions, idempotency (behavior when the user is already a member), or error conditions for a mutation that changes access rights.

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?

A single sentence with the action front-loaded and the side effect parenthetically attached. No filler or redundancy.

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?

For an unannotated access-granting mutation, the description should cover permissions and idempotency; it only covers the SharePoint side effect. The simple two-parameter, fully documented schema keeps the gap moderate rather than severe.

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 both parameters are already documented as user_id (ID or UPN) and group_id. The description adds no additional meaning such as accepted formats, batch support, or whether group_id accepts names as well as IDs. Baseline 3 is correct when the schema does the work.

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?

States a specific verb and resource ("Add a user to a group") plus a scope note about the resulting access. An agent can distinguish it from remove_user_from_group by the verb, though no sibling is named explicitly.

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 when-to-use guidance, no prerequisites (must the group exist? must the user be an existing member?), and no mention of remove_user_from_group as the inverse operation. The tool name implies its purpose, but the description adds nothing about invocation context.

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