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

Annotations declare destructive/idempotent/openWorld but say nothing about semantics. The description adds real behavioral content: ban prevents rejoining, add lifts an existing ban, and the caller can leave by acting on their own ID even for hidden or blocking spaces. It still omits rate limits, permission requirements beyond ownership, and effects on the member's existing content.

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?

A single front-loaded sentence covering the full operation set and the ownership/hidden-space qualifiers. No filler, nothing redundant.

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?

With no output schema needed and annotations already carrying the safety profile, the description supplies what an agent needs to call correctly: the ownership precondition, the action outcomes, and the self-leave pathway for hidden/blocking spaces.

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 every parameter (including the action enum semantics and the self-ID leave case) is already documented in the schema. The description restates the action semantics without adding format, ordering, or edge-case detail beyond what is structured. 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?

The description names specific verbs (add, remove, ban, leave) against a specific resource (a member of a space), and states the ownership precondition. It never names the closely related siblings (invite, join_space, block, moderate) that overlap with 'add' and 'ban', so the agent must infer the boundary.

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?

'A space you own' establishes a prerequisite, and 'or leave a space, including one that is hidden or blocks you' hints at a use case. But there is no guidance on when to use this versus invite to add a member or block/moderate to restrict one, nor any exclusion rules.

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