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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive call; the description adds genuinely useful context beyond that: the owner-only authorization requirement and the 7-day renewal behavior on expiry. It does not mention rate limiting or delivery-failure behavior for an email-sending operation.

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?

One sentence with zero waste: action, target population, side effect, and permission gate are all front-loaded before any secondary detail.

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 two-parameter mutation with no output schema, the description covers the action, eligibility, expiry renewal, and authorization. It stops short of describing the result (e.g., what a failed resend returns), but nothing essential to calling it correctly is missing.

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?

With 100% schema description coverage, the schema already documents both 'email' and 'company' including the slug-or-id format. The description adds no parameter-level syntax or format detail, so the baseline 3 applies.

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?

Specific verb (send again) + resource (invitation email) + precise scope: only people already invited to the company who have not yet joined. Distinguishable from siblings like add_member and remove_member without opening the schema.

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?

States the eligibility condition (person invited but not joined) and the permission prerequisite ('Company owners only'), which tells the agent when the call is valid. It does not name alternatives such as add_member when no invite exists, so it falls short of a 5.

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