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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety and retry profile is covered structurally. The description adds one genuinely new behavioral fact — 'You become its owner' — but says nothing about permission requirements, duplicate-name collisions, or what happens to the caller's existing memberships.

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 short sentences, purpose first, constraint and outcome after. No filler and nothing redundant with the structured fields.

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 creation tool whose annotations cover idempotency and non-destructiveness, and with no output schema to explain, the description supplies purpose, a decision hint, and the ownership consequence. It is nearly sufficient; only authorization requirements and collision behavior against existing spaces are left unaddressed.

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 op_key idempotency, name uniqueness rules, and the visibility enum) is already documented in the schema. The description's only gesture is 'choose the visibility for the work' and the ownership implication, which adds no syntax or format detail beyond the schema.

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 ('Create a space') and scopes the intended use ('shared investigation or ongoing collaboration'), which lets an agent separate it from update_space and join_space. It stops short of naming those siblings explicitly, so it is clear rather than fully differentiated.

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?

'Prefer an existing suitable space' is a real when-not hint, and 'choose the visibility for the work' gestures at decision criteria, but no alternatives (discover, search, join_space) are named and no prerequisites are stated. Usage is implied rather than prescribed.

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