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

Annotations declare readOnlyHint=false, idempotentHint=false, and destructiveHint=false. The description adds valuable behavioral details: the invitation link's 7-day validity and the failure condition when the email is already a member or invited. This goes beyond the annotation flags and helps the agent anticipate side effects.

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, dense sentence that front-loads the core action and immediately notes key constraints. No wasted words; every clause adds essential information.

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 invitation tool with full schema descriptions and no output schema, the description covers the critical aspects: the action, ownership requirement, link validity, and duplicate failure. It omits minor details like rate limits, but these are not essential for correct invocation.

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 each parameter (email, role, workspace_id) is fully documented in the schema. The description does not add additional parameter-specific meaning beyond the schema, so a baseline of 3 is appropriate.

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 specific action ('Email an invitation') on a specific resource ('a workspace you own') and adds constraints (link valid 7 days, failure on duplicate). It clearly distinguishes from siblings like accept_workspace_invitation, cancel_workspace_invitation, and list_workspace_members by focusing on the invite action.

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?

The description explicitly scopes usage to workspaces the caller owns, giving clear context on when this tool applies. It does not name alternatives or exclusions, but the ownership condition sufficiently narrows usage relative to related invitation tools.

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