users_inviteCreate a new user and send an invitation email to join. Assign an optional role to set their access level.
Create a user and send an invitation email
| Name | Required | Description | Default |
|---|---|---|---|
| Yes | User email address | ||
| role_id | No | Role ID to assign | |
| last_name | Yes | Last name | |
| first_name | Yes | First name |
Changes observed during successful MCP inspections.
v0.2.27Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true). The description does add one genuinely useful behavioral fact not in the annotations: an invitation email is dispatched as a side effect. It does not disclose whether the email send is reversible, what happens on duplicate emails, or whether the user is created in a pending state.
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?
A single sentence with zero filler, and the primary action is front-loaded before the side effect. It is efficient, though arguably under-specified for a tool with an irreversible email side effect.
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 mutation tool with an outward-facing side effect and no output schema. The description does not say whether the invite can be resent, whether the created user is pending until acceptance, whether role_id defaults, or what a duplicate invitation does — real gaps for an agent calling it.
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 100%, so all four parameters (email, first_name, last_name, role_id) are documented in the schema; baseline 3 applies. The description adds no parameter-level meaning, e.g., that role_id is optional or what role is assigned by default.
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?
States a specific verb pair ('Create a user') plus the notable side effect ('send an invitation email'), which cleanly separates it from users_list, users_get, users_delete, and even signup. It stops short of naming any sibling or clarifying how it differs from self-service signup, so it misses the top mark.
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 when-to-use guidance, no mention of prerequisites (e.g., admin role), and no alternative such as signup or users_create-equivalent is referenced. The agent must infer that this is the admin-initiated path from the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.