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

With no annotations at all, the description carries the full burden of behavioral disclosure, but it only says 'Open (or update)' without explaining side effects, persistence, authorization requirements, or whether the operation is idempotent. The agent cannot anticipate what state changes will occur.

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?

The description is concise with no filler words, but it is under-specified rather than efficiently structured. The single sentence earns its place, yet it omits crucial context that could be conveyed in a few more sentences.

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?

Given the tool has 4 parameters, no annotations, no output schema, and zero schema description coverage, the description is grossly incomplete. It does not explain what a memory space is, what opening entails, how updates are determined, or what the result of the operation looks like.

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 0%, and the description adds no meaning to the parameters. It does not clarify what 'owner', 'name', 'kind', or 'description' mean in the context of a memory space, nor how they affect the open/update behavior.

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 states a specific verb ('Open') and resource ('memory space'), and parenthetically notes the update behavior. It is clear enough to identify the core action, though it does not differentiate from sibling tools like write_memory or search_memory.

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?

The description gives no guidance on when to use this tool versus alternatives such as write_memory, search_memory, or my_spaces. There is no mention of prerequisites, typical use cases, or conditions under which opening vs updating applies.

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