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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true), and op_key in the schema documents retry idempotency. The description adds one real behavioral fact beyond that — 'You become its owner' — but omits permissions needed, effects on membership, and any limits.

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, no waste, front-loaded with the purpose before the routing advice and the ownership consequence. 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?

With full schema coverage, annotations, and no output schema, the description needs only to convey purpose, ownership effect, and routing. It does that, though it stops short of stating permissions/visibility defaults for a mutation that grants ownership.

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 seven parameters including the visibility enum are already documented in the schema. The description's note about choosing visibility adds framing but no syntax or meaning beyond what the enum description provides; 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?

States a specific verb and resource ('Create a space') and scopes the purpose to 'shared investigation or ongoing collaboration', which clearly separates it from siblings like update_space, join_space, and create_capability. An agent can identify the right tool without opening any 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?

'Prefer an existing suitable space' is a genuine when-to-use cue, but it never names the alternative tool (e.g. discover or search) that would find one, nor any prerequisite for creating. Usage is implied rather than explicit.

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