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

Annotations declare mutation/destructive/openWorld traits; the description goes further by disclosing the failure mode ('past that the invite is payment_required') and a gating condition (owner email must be verified). It omits idempotency behavior (duplicate invites) and whether the invite expires, which the non-idempotent hint makes relevant.

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?

Four compact sentences, front-loaded with the action, then roles, then prerequisites, then plan limits. No filler or restatement of the name.

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 roles, prerequisites, plan limits and the payment_required outcome, which is what an agent needs to call it correctly. Return/confirmation behavior and duplicate-invite handling are the only gaps.

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 coverage is 0%, so the description carries the burden, and it does explain all three role enum values with their actual permissions (ADMIN includes billing, SCHEDULER books appointments, DOCK_STAFF marks trucks). The email parameter is self-evident; only format/validation details are missing.

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 and resource ('Email someone an invitation to join the organization') and no sibling tool competes for this action, so an agent can route to it unambiguously.

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?

Gives a hard prerequisite ('Needs the owner's email confirmed first') and a plan constraint, which tells the agent when the call will succeed. It does not name alternatives or state when not to use it, but the prerequisites are explicit and actionable.

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