list_channel_messages

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

With no annotations, the description carries the full burden. It discloses the return format, pagination via next_page_token, the effect of include_body and include_raw, the default limit, and the Graph cap of 50. It also notes that card text feeds the snippet, which is a non-obvious behavior. No contradictions with annotations (none present).

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 efficiently structured with clear Args and Returns sections. Each parameter gets a single line, and the overall text is compact yet thorough. No redundant sentences; every clause adds information.

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?

The tool has no output schema, but the description fully specifies the return object shape and pagination. It covers all parameters, defaults, and constraints, and even clarifies a sibling tool for replies. It is complete for an agent to call it correctly without additional lookup.

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%, so the description fully compensates by explaining every parameter: team_id, channel_id, limit (with range and default), page_token, include_body (with detailed effect), and include_raw. It adds constraints and context far beyond the schema's bare type definitions.

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 clearly states the tool lists root messages in a channel, newest first, and explicitly distinguishes itself from replies by noting they are fetched separately. The verb 'list' and resource 'channel messages' are specific, and the sentence 'Replies are not included here' differentiates it from sibling tools like list_message_replies.

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?

It explicitly states when not to use it (for replies) and provides the alternative tool (list_message_replies). It also references how to obtain the channel_id (from list_channels), giving clear context on prerequisites. This meets the 'explicit when/when-not/alternatives' standard.

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