List scheduled messages

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

With readOnlyHint=true, the safety profile is already exposed. The description adds useful behavioral context: messages are 'pending', 'timed', and returned 'soonest first'. It does not describe return format, pagination, or the effect of guild filtering, but for a simple read-only list tool this is acceptable. No contradiction with annotations.

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 two short sentences, front-loaded with the essential purpose, and includes a useful clarification about events. There is zero wasted text; every clause serves a purpose.

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 one optional parameter and no output schema, the description sufficiently covers what the tool does and how it relates to schedule_message. It could explicitly mention the guild parameter's role, but since the schema already covers it, this is not a major gap. The mention of 'soonest first' conveys ordering behavior.

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%: the only parameter 'guild' is described in the schema as 'Guild (server) name or ID. Omit to use the default guild.' The tool description adds no additional meaning about this parameter, so the baseline of 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 clearly states the tool lists 'pending timed messages waiting to send' and specifies ordering ('soonest first'), which precisely defines the tool's function. It also explicitly distinguishes from sibling 'list_events' by noting these are not Discord community events, making the purpose 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 provides clear context for when to use this tool: to view messages queued via schedule_message. It explicitly names the alternative list_events for community events, effectively telling the agent when not to use the tool. However, it does not cover all possible alternatives (e.g., list_messages for regular messages) or provide extensive usage scenarios.

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