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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral context beyond that: publication is handled by an external scheduler polling every 60 seconds, which tells the agent the change is eventually applied rather than immediate. It does not contradict any annotation.

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?

Three short sentences, front-loaded with the action and its scope constraint. The future-time requirement is stated in the body and then again in the schema, a small redundancy, but there is no filler otherwise.

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 tool with full schema coverage and complete annotations, the description covers the key unknowns: draft applicability and the 60-second scheduler latency. It omits failure behavior (invalid/past timestamps, unknown post_id) and there is no output schema, so the response shape remains unstated, but that is a minor gap at this complexity.

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%, so both parameters are fully documented with UUID format and ISO 8601 timezone requirements already in the schema. The description only restates the future-time rule that the schema also states, adding no further meaning beyond the structured fields.

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 ('Change the scheduled time of a post') and clarifies the scope by noting it applies to both scheduled posts and drafts. It stops short of naming the adjacent siblings (schedule_post, update_post, cancel_scheduled) it should be distinguished from, so an agent must infer the boundary itself.

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 a clear applicability rule: use it for scheduled posts or to schedule a draft, with the constraint that the new time must be in the future. It lacks explicit exclusions or alternatives – nothing says whether to prefer update_post or schedule_post when a post has no schedule yet – so the routing is left partly to inference.

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