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

Annotations already declare destructiveHint=true, idempotentHint=false, and openWorldHint=false, so the safety profile is covered. The description adds genuinely new context about approval requirements (org-configurable MCP approvals plus always-on business workflow approvals), but it never warns what the destructive behavior is: whether omitted fields are cleared, whether the member can be removed this way, or whether an approval gate blocks the call.

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?

Two short sentences with no padding, and the core action is front-loaded. The second sentence is boilerplate approval text that is only loosely connected to the edit operation, so it earns its place only marginally.

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?

This is a destructive, non-idempotent mutation over a nested payload, and an output schema exists so return values need not be explained. Still missing are the editable field set, partial-vs-full update semantics, and what the approval sentence actually means for calling this tool, leaving the agent under-informed for a 3-parameter destructive write.

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?

Schema description coverage is 0% and all three required parameters (siteId, memberId, nested data with role/team/addedAt) are undocumented in both places. The description mentions only "assignment" generically and does not clarify that data is a partial-update object or what the team enum values mean, so it fails to compensate for the coverage gap.

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 pairs the verb "Edit" with a specific resource, "a site team member's assignment," which separates it from add_site_team_member and remove_site_team_member. It stops short of naming which aspects of the assignment are editable (role, team, addedAt), so the boundary with sibling update_* tools is only partly drawn.

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?

There is no statement of when to use this tool versus list_site_team, add_site_team_member, remove_site_team_member, or update_organization_user. The approval sentence describes a constraint on the operation rather than guidance for choosing this tool.

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