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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses pagination behavior ('latest page by default', continuation via next_cursor), which is real context beyond the schema. However, it says nothing about rate limits, required permissions, or the recheck/proof flow that the token hints at, leaving meaningful gaps.

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 zero filler; the default behavior is front-loaded and the pagination guidance follows. 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 no output schema and no annotations, the description is the main carrier of behavior for a 6-parameter, nested-object tool. It covers default paging and cursor math adequately, but omits limit/before semantics and any response or auth context, leaving it minimally complete rather than thorough.

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 only 33%, so the description must compensate: it clarifies the semantic split between since (Unix time) and after (next_cursor continuation) that the bare schema fields do not. It leaves limit, before, and proof's placement in the paging flow unexplained, so it only partially closes the gap.

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 clear resource and scope: 'Messages from all rooms' with 'latest page by default,' which is a concrete read operation. It implicitly contrasts with the single-room siblings (lockzone.read, lockzone.key_messages) via 'all rooms,' but never names an alternative explicitly, so it falls short of a 5.

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 implied by 'from all rooms' (the broadcast read vs. room-scoped reads), but no sibling is named and no when-not-to-use guidance is given. The since-vs-after instructions are pagination mechanics rather than tool-selection guidance.

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