List message replies

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the behavioral detail of ordering ('most recent first'), which is not in annotations. This is valuable and does not contradict any annotation.

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, compact sentence with no filler. The main purpose is front-loaded, and every word earns its place. It is concise without sacrificing clarity.

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 list tool with fully documented parameters and safe read-only annotations, the description is complete. It does not explain return format, but that is not required since there is no output schema and the tool's behavior is straightforward. No missing information would prevent 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 description coverage is 100%, meaning all four parameters (top, team_id, channel_id, message_id) have their own descriptions in the input schema. The tool description does not add any parameter-specific information, but the schema already handles this. Baseline 3 is appropriate.

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 specific verb ('List'), a specific resource ('replies in a channel message's thread'), and an ordering detail ('most recent first'). It clearly distinguishes from siblings like list_channel_messages (which lists channel messages, not replies) and get_channel_message (single message). The purpose is unambiguous.

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 description implies when to use the tool: when you need replies to a specific message. However, it does not explicitly mention alternatives or exclusions (e.g., 'use list_channel_messages for channel-level messages'). The context is clear, but there is no explicit when-not guidance, so it stops short of a 5.

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