Get Channel Messages

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the dual list/single-read behavior, which is useful context, but it does not disclose pagination behavior, output shape, or any access requirements. No contradiction with annotations exists.

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 efficient sentence with the action verb front-loaded and no filler words. It is appropriately compact, though it could have been more informative without becoming bloated, which is why it does not reach 5.

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 tool has 7 parameters, 32 sibling tools, and no output schema, the description is minimally adequate. The schema covers parameters and annotations cover read-only/idempotent behavior, but the description leaves unclear when each mode applies and how this tool relates to similar ones like get_chat_messages or get_channel_message_replies.

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%, so parameters are fully documented in the input schema. The description only lightly gestures at messageId/replyId ('read one message or reply by ID') without adding format, precedence, or interaction details beyond the schema, so it does not elevate above the baseline.

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 names a specific verb ('List'/'read') and resource ('channel messages'), and clarifies three modes: list, read one message, read one reply. It is not a tautology, and the 'reply by ID' clause distinguishes it from a plain listing tool, though it does not explicitly contrast with siblings like get_channel_message_replies or get_chat_messages.

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?

No guidance is given on when to use this tool versus alternatives. It does not mention that get_channel_message_replies is better for reply threads, that search_messages is for searching, or that get_chat_messages covers direct messages instead of channels. The only implied guidance is 'read channel messages,' which is weak for a tool with many siblings.

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