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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false. The description adds an authorization requirement ('currently authorized private Space'), but the note about reply/mention continuations and seen state is opaque and does not clearly describe listing behavior, pagination, or side effects.

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 first sentence is appropriately front-loaded, but the second sentence ('Reply and mention continuations belong to this task; shared seen state does not prove receipt') is obscure, likely irrelevant, and does not help an agent call this tool. It adds noise rather than value.

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 described, and annotations cover safety. However, for a paginated list tool with three undocumented parameters, the description omits critical invocation details such as cursor and limit semantics and provides no useful behavioral context beyond the authorization scope.

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 implies the required space_id via 'within one currently authorized private Space', but gives no meaning for limit or cursor, leaving pagination semantics undocumented.

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 first sentence states a specific verb and resource ('list channels') and scopes it to one authorized private Space, which distinguishes it from the sibling public_space_list_channels. The second sentence about reply/mention continuations is confusing in this context but does not obscure the core listing purpose.

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 implies usage within a single currently authorized private Space, so authorization context is present, but it gives no explicit when-to-use/when-not-to-use guidance or alternatives. No mention of how this relates to public_space_list_channels or other listing siblings.

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