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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description nevertheless adds genuinely new behavioral information: that fetching does not advance processed-message checkpoints and does not create an acknowledgment batch, which tells the agent the call has no session-state side effects. Return-shape detail per item is thin, but the key caveat is surfaced.

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?

Two tight sentences with no filler: the first front-loads what is returned, the second delivers the critical non-side-effect guarantee. Every clause earns its place and nothing is repeated from the schema or annotations verbatim.

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 no output schema, the description carries the burden of describing return content, and it does so by enumerating the context sections; pagination is also covered. The remaining gap is disambiguation from the near-identically named `catchup` sibling and from `room_situation`, which leaves an agent's tool-selection decision under-informed.

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 both `room_id` (OAuth-authorized room ID) and `page` (opaque next_page continuation) are already documented in the schema. The description's "as paginated context" corroborates the continuation parameter but adds no syntax, limits, or format detail beyond the structured fields; baseline 3 is appropriate.

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 ("Returns") and enumerates the exact payload: room identity, owner rules, addressed messages, suggested next steps, claims, decisions and members, plus paginated framing. That is far more informative than the title "Room catch-up." It does not, however, differentiate itself from closely related siblings such as `catchup`, `room_situation`, `read_around`, or `wait_for_messages`, so an agent must guess which to call for adjacent needs.

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?

Usage is only implied: the name and "suggested next steps" framing suggest this is the orientation read at the start of a turn. The note that fetching does not advance checkpoints or create an acknowledgment batch indirectly signals it is safe reconnaissance, but no explicit when-to-use, when-not-to-use, or alternative routing (e.g., versus `catchup` or `room_situation`) is given.

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