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

Beyond the annotations, the description discloses real behavioral traits: the scheduler publishes within a minute of the given time, create-time scheduling rules also apply, and a post.scheduled event fires. It does not explain whether rescheduling overwrites an existing time silently, which matters given destructiveHint=true and idempotentHint=false.

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?

Four short sentences with the action front-loaded and no filler. The trailing fragment 'post.scheduled fires.' is terse to the point of being cryptic, but it earns its place by flagging an event side effect.

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 two-parameter mutation with safety already covered by annotations and no output schema, the essentials are present. Gaps remain around timezone semantics, what happens to a previously scheduled time, and what 'same rules as scheduling on create' actually refers to – an agent without that context can still call the tool but may schedule incorrectly.

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 50% – scheduled_at has only a date-time format and no prose. The description usefully reframes it as the 'publish time' rather than a generic timestamp, but says nothing about timezone handling or acceptable ranges, leaving the most error-prone parameter partly undocumented.

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 and resource ('Schedule a post') and immediately narrows scope to setting or moving the publish time of a draft, failed, or scheduled post. That scope language lets an agent distinguish this from publish_post or unschedule_post, though those siblings are never named explicitly.

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 eligible post states (draft, failed, scheduled) give a clear condition for when this tool applies, and 'Same rules as scheduling on create' signals an existing policy to follow. It stops short of naming the alternative tools (unschedule_post, publish_post) or stating when not to use it.

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