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

The annotations already establish that this is a safe, non-destructive, closed-world read. The description adds useful behavioral context: results are oldest-first, pagination continues on mentions.has_more, cursors are task-specific, and shared seen state is not sufficient proof of receipt.

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 compact and front-loads the core operation in the first sentence. The remaining sentences add pagination and cursor guidance without filler, though the phrasing is somewhat jargon-heavy for an unassisted reader.

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?

An output schema exists, so return values need not be fully documented. However, with zero schema descriptions on all input parameters, the description is still incomplete for an agent that needs to understand space_id, limit, and cursor inputs beyond their raw schema constraints.

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%, so the description must compensate for all three parameters. It mentions the cursor concept and mentions.has_more, but it does not explain space_id requirements, the limit parameter, or the cursor format and constraints provided only by the JSON 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?

The description uses a specific verb and resource: reading oldest-first mention pages. It scopes the operation to one currently authorized private Space, which clearly separates it from the public-space mention sibling and from thread/reply tools.

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 clear usage context for paginating mentions: continue while mentions.has_more is true and do not mix this cursor with thread reply or enumeration cursors. It does not explicitly name when to prefer a sibling tool such as private_space_list_threads, so it stops short of full alternative-based guidance.

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