apple_messages_list_chats

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds real value beyond them by disclosing the hard platform limitation that message bodies/history are unavailable, which prevents an agent from mis-planning a follow-up read.

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 read-only posture and the returned resource, with no filler. The limitation caveat is placed immediately after the purpose so it is read before the agent commits.

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 does reasonably well by naming the returned fields, and it covers the key capability limit. It still omits pagination behavior (limit default 20, max 100) and the meaning of accountId, which an agent needs to page or scope correctly.

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% for all three parameters, so limit, offset, and accountId are undocumented in both places. The description never mentions pagination or what accountId refers to (presumably an id from apple_messages_list_accounts), leaving the schema gap entirely uncompensated.

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?

States a specific verb and resource (list Messages chats) and enumerates what is returned: chat metadata and participant handles. It also distinguishes itself from apple_messages_send and apple_messages_list_accounts by scoping to chats rather than sending or accounts.

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 sentence 'Apple scripting does not expose message history' implicitly tells the agent this is the ceiling of what Messages data is reachable, which is useful routing context. However, it never names a sibling alternative or states when to prefer this over apple_messages_list_accounts, so usage is only implied.

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