List scheduled messages

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds real value beyond them by clarifying that scheduling happens client-side and this tool only reads back what is queued, preventing the agent from assuming it can schedule. It stops short of describing pagination or the return shape.

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?

Two tight sentences, front-loaded with what the tool returns and followed by the key behavioral clarification. No filler.

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 read-only list tool with annotations and no output schema, the description conveys what is returned and the read-only nature. However, with 0% schema coverage the parameters remain undocumented, leaving a real gap 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 description coverage is 0% for two parameters. The description only implicitly references the required 'chat' via 'in a chat' and never explains its accepted format (id, username, etc.), and 'limit' is not mentioned at all, so it fails to compensate for the coverage gap.

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?

States a specific verb (List) and resource (messages queued to be sent later), scoped to a chat and including the planned send time. The purpose is unambiguous and no sibling tool covers scheduled messages, though it doesn't explicitly contrast itself with any sibling.

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?

Usage is only implied: an agent can infer you call this to inspect queued messages, but there is no when-to-use statement, no exclusions, and no named alternative (e.g., send_message for actually queuing). The second sentence clarifies behavior rather than selection guidance.

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