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add_site_permission

Assign read, write, or owner permissions to a user on a SharePoint site using site ID and user ID, enabling controlled access for Microsoft 365 site administration.

Instructions

Add a user permission to a SharePoint site

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": {
      "site_id": "<site_id>",
      "user_id": "<user_id>"
    },
    "name": "add_site_permission"
  }
}

Input Schema

Name	Required	Description	Default
`role`	No	The permission level: read, write, or owner	write
`site_id`	Yes	The site ID
`user_id`	Yes	The user ID to grant access

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Nov 2, 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 the full burden. It does not disclose the required admin permissions or what happens if the user already has a permission (overwrite, error, or duplicate). It also says nothing about the default 'write' role granting fairly broad access, or about the response format.

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, front-loaded sentence with no waste. It is short enough to border on under-specification.

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?

This is a permission-granting mutation with no annotations and no output schema. It needs more context on side effects, idempotency, prerequisites and the return value than the description provides.

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%, with an enum and a default for role, so the baseline is 3. The description adds nothing about parameter formats or where to obtain the IDs.

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?

"Add a user permission to a SharePoint site" gives a specific verb and resource, and it is clearly distinct from remove_site_permission and list_site_permissions. It does not say how it differs from add_user_to_group, which is another way to grant access.

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 grant direct site permissions versus adding a user to a group. It also omits prerequisites, such as getting site_id from list_sites or get_site_by_url, or user_id from search_user.

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