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

Annotations already declare destructiveHint=true, readOnlyHint=false, openWorldHint=false and idempotentHint=false, and the description does not contradict them. It adds genuinely useful context beyond them: the state transition (scheduled → draft), that content survives, no LinkedIn side-effect, and the confirm gate. It never addresses re-invocation behavior, which matters given 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, front-loaded with the action and its effect, then constraints. Every clause carries information; the PostPen calendar analogy is the only slightly decorative element, but it usefully concretizes 'move to draft'.

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 no output schema and full annotation coverage, the description supplies the state transition, refusal condition, and the published-post restriction an agent needs. The only gap is behavior on repeat invocation, which the non-idempotent annotation flags but the description leaves unexplained.

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% and both params are documented there, including that id comes from list_posts status scheduled. The description restates the confirm requirement ('Refused unless confirm is true') but adds no syntax or edge-case detail beyond the schema, so baseline 3 applies.

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 ('moves a scheduled post ... back to Drafts') plus the exact effect ('clears its schedule time'), and explicitly carves out what it is not ('does not delete the post', 'does not call LinkedIn'). The calendar analogy pins down the semantics, so an agent can separate it from delete_draft and schedule_post without opening a schema.

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?

Gives clear preconditions: 'Refused unless confirm is true' and 'Published posts cannot be unscheduled', which tells the agent when the call will fail. It stops short of naming an alternative tool (e.g. delete_draft or publish_now) or describing what to do when the post is already published, so it falls below the explicit when-not/alternatives bar.

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