list_scheduled_messages

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

readOnlyHint=true already tells the agent this is a safe read. The word 'pending' adds one useful behavioral fact (only unsent messages are returned), but the description is silent on pagination despite a cursor parameter, and says nothing about result size or ordering.

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?

A single front-loaded sentence with no filler, which is good, but the brevity comes at the cost of under-specification for a two-parameter paginated tool. It is terse rather than genuinely economical.

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?

With no output schema, no annotations beyond readOnlyHint, and 0% schema description coverage, the description carries most of the burden and does not deliver: return shape, pagination behavior, and cursor usage are all missing.

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% and there are two parameters. The description covers only 'channel' (as an optional filter) and gives no format or ID semantics for it; 'cursor' is completely undocumented in both the schema and the description, leaving pagination unexplained.

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 noun phrase identifies the resource and scope ('your pending scheduled messages'), which lets an agent separate it from schedule_message and delete_scheduled_message. However, it lacks an explicit verb (list/retrieve) and never contrasts itself with the sibling tools, so the purpose is only implied rather than stated.

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?

'optionally for one channel' hints at one usage mode but gives no when-to-use context, no prerequisites, and no routing against alternatives like delete_scheduled_message or schedule_message. An agent must infer that this is the read counterpart to those tools.

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