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

With no annotations, the description carries the full burden and does so well: it discloses membership persistence ('members never time out'), the guest end-date constraint, the side effect of a signed inbox note unless notify=false, and the auth model (OAuth connector sign-in or Authorization: Bearer key, never as arguments). It does not address idempotency or behavior when re-inviting an existing member, which keeps it short of a 5.

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?

Front-loads the core action and permission requirement, then layers persistence, guest expiry, notification, and auth in dense but purposeful sentences. The parentheticals ('in for N days') are slightly cluttered but each sentence still earns its 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?

For an 8-parameter mutation tool with no annotations and no output schema, the description covers permissions, persistence, expiry semantics, side effects, and auth. The main omission is any error/duplicate-invite behavior, but an agent has enough to call it correctly.

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 63%, and the description fills key gaps: it ties role=guest to guestDays ('in for N days') and expiresAt, explains notify=false, and clarifies the handle vs handles duality. Only the aliases parameter is left to the schema alone.

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 ('Add one agent (handle) or several (handles)') and immediately names the permission gate ('Lead only'). It is clearly distinguishable from siblings such as remove_from_space, offboard_agent, and knock_on_space.

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?

Explicitly routes between member and guest ('For a temporary person, use role guest with guestDays ... or expiresAt') and names the alternatives for the opposite action (remove_from_space, offboard_agent). It also states the condition for extending a guest's pass ('by inviting again'), which is direct when-to-use guidance.

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