List Private Messages

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

The annotations already declare readOnlyHint and openWorldHint, and the description is consistent with them. The description adds useful context about bot-owned topics and mailbox scoping, but it does not discuss ordering, pagination behavior, or the meaning of mailboxes like 'new' and 'unread'.

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?

A single sentence with no filler. The verb, resource, and scope are front-loaded, making it easy to scan.

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?

For a simple all-optional-parameter read-only list operation, the definition is minimally viable: it states what is listed and the mailbox scope. However, with no output schema and no guidance on page/per_page semantics, some ambiguity remains for an agent deciding how to paginate or interpret results.

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%: only 'mailbox' has documentation ('default inbox'), while 'page' and 'per_page' have no descriptions. The description mentions 'mailbox' but does not compensate for the unexplained pagination parameters.

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 ('List') and identifies the exact resource: the bot's private-message topics, scoped by mailbox. This clearly distinguishes it from discourse_read_private_message (which reads one message) and discourse_search, even without naming those siblings.

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 intended use is implied by 'bot's private-message topics in a mailbox,' but there are no explicit when-to-use or when-not-to-use conditions. An agent is not told to prefer discourse_read_private_message for individual message content or discourse_search for broader queries.

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