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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description adds substantial value beyond them: what actually gets destroyed (the schedule, not the draft), that the call is safe to repeat, the refusal windows, the required `publish` scope (or admin), the Pro plan requirement, and that each publish counts against the monthly direct-post quota.

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?

The behavioral core is front-loaded before the plan/billing details, and nearly every sentence carries information. It is dense rather than padded, though the bracketed '[PUBLISHES to social accounts · `publish` scope]' header is slightly confusing on a cancel tool.

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, the description still conveys the outcome (post marked cancelled, draft preserved) and all preconditions (scope, plan, timing refusal), which is everything an agent needs to invoke it correctly.

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 the single `id` parameter is fully documented in the schema (convexPostId from publish, or posts[].id from content). The description adds no further syntax or format detail, so the baseline of 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+resource ('takes a SCHEDULED post off the platform schedule and marks it cancelled') and clarifies the resulting state ('the draft stays, so it can be published again'). This is clearly distinguishable from siblings like update_scheduled_post, delete_content, or publish.

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 concrete when-to-use context and exclusions: refused within 5 minutes of the slot, and when the platform will not remove it (some YouTube uploads), plus 'Confirm with the user first.' It does not explicitly name alternative tools for the blocked cases, so it stops short of 5.

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