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

Annotations only declare non-read-only, non-destructive, and closed-world; the description adds real behavioral context beyond them: the caller must own the Space, generic invitations require later owner approval, and no WorkOS organization is needed. It stops short of covering idempotency behavior or failure modes.

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 sentences, no filler, and the primary mode is front-loaded ahead of the conditional variant. All three sentences-worth of content earn their place.

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?

An output schema exists so return values need no explanation, and the ownership prerequisite is stated. But for a zero-coverage, three-parameter mutation tool the description leaves the parameter roles and idempotency semantics unexplained, which is a meaningful gap.

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 none of the three parameters have prose descriptions, so the description must carry the load. It only hints at contact_token via 'contact-token recipient' and never makes explicit that omitting it produces the generic invitation; idempotency_key — a required parameter — is never mentioned at all.

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 names a specific verb and resource (invite a member to a private Space) and splits it into two concrete modes: contact-token invitation and generic invitation with owner approval. It never names which sibling to use instead (e.g., private_space_approve_invitation or private_space_list_invitations), so differentiation from siblings is left to inference.

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 phrase 'a private Space you own' implies an ownership precondition, and the second clause implies that generic invitations are for recipients who request access. However, it never states explicitly when to pick one mode over the other, nor does it point at alternatives such as approve_invitation or accept_invitation.

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