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

Annotations already declare destructiveHint=true and openWorldHint=true, so the mutation risk is visible; the description adds meaningfully beyond that by flagging the authorization requirement and the concrete consequence that visibility changes 'can expose or remove its contents from public access'. It does not clarify whether omitted fields are preserved (partial vs. full update), which is the remaining gap.

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?

Three compact sentences, no redundancy: triggers first, behavioral consequence second, prerequisite last. Every clause 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 a 5-parameter mutation tool with no output schema and full schema coverage, the description covers purpose, triggers, prerequisites, and the public-exposure risk. The one omission is update semantics — whether unspecified fields remain unchanged — which an agent would want before calling.

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 all five parameters are already self-documenting; the description adds no syntax, format, or default information beyond what the schema states. Baseline 3 applies when the schema carries the load.

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 (update) and resource (Space) and enumerates the exact mutable facets: rename, description, visibility, publish state, and public slug. This lets an agent distinguish it from update-space-item or update-space-document 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?

It gives clear triggering conditions ('Use this when the user wants to rename a Space, edit its description, make it public/private...') and a prerequisite routing hint ('Requires numeric space_id from list-spaces'). It stops short of naming an explicit alternative or when-not condition, which keeps it below a 5.

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