get_friend_msg_history

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

No annotations are provided, so the description carries the full burden. It only says 'Get', implying a read operation, but does not disclose ordering, pagination, whether it returns only messages from the specified user, or any rate limits. It also doesn't state what the response contains. For a read tool without annotations, this is a significant gap.

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?

The description is a single short sentence with no fluff, which is appropriately concise for the tool's simplicity. However, it could have incorporated useful context (like pagination hints) without becoming verbose. It is front-loaded with the core action, but the brevity leaves some expected context out.

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?

Given the lack of output schema, annotations, and the existence of closely related sibling tools, the description is incomplete. It does not explain the return format, how to paginate (e.g., using message_seq), or how this relates to get_group_msg_history. An agent would have to guess at expected behavior, which is inadequate for correct invocation.

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 100% for all three parameters (count, user_id, message_seq), so the schema already provides definitions. The description adds no additional meaning beyond the schema. Baseline 3 is appropriate because the schema handles the parameter documentation, and the description does not contradict or enrich it.

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 'Get friend message history' uses a clear verb+resource and distinguishes from group-focused siblings like get_group_msg_history and read_group_messages by explicitly stating 'friend'. It is not a tautology and the purpose is evident, though it could be more specific about scope (e.g., private one-on-one messages) but it's sufficient.

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 use this tool versus alternatives like get_group_msg_history or read_group_messages. It does not mention any preconditions, differences in message scope, or when to prefer one over the other. An agent has no clues to select this tool over similar ones beyond the name.

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