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

Annotations already establish readOnlyHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description does add useful pagination behaviour (50 per page, cap 200), but its only instruction for continuing, 'Pass `next` from the last answer', refers to a field that does not exist in the schema, which will mislead the agent at the exact moment it needs to page.

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 short sentences, front-loaded with the resource and sort order, with no filler. The phrase 'as before' is slightly opaque but does not bloat the text.

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 should be the authority on paging, yet it points at the wrong cursor field and leaves 'before' unexplained, so an agent cannot reliably fetch page two. It also omits how this differs from search_chats, which matters in a 46-tool sibling set.

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 coverage is only 33%: brand is documented in the schema, limit and before are not. The description partially compensates for limit by giving the effective page size and cap, but it never explains 'before', and it introduces a phantom 'next' cursor that conflicts with the actual cursor-shaped parameter 'before'. This is worse than silence because it sends the agent toward a non-existent argument.

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 names the resource and its ordering ('The chat list, latest activity first'), so an agent knows it retrieves a list of chats. It does not distinguish the tool from siblings like search_chats or list_needs_you, which keeps it 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?

There is no guidance on when to call this rather than search_chats (filtered retrieval) or list_needs_you (queue view). The agent must infer the distinction from the tool names alone.

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