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

Annotations already declare destructiveHint=true, idempotentHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavior: the 409 failure condition, the downstream side effect that scheduled posts are also cancelled on the publishing provider, and the cost ('Free'). It does not describe what happens to the row post-call, keeping it out of the top band.

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 post states, then the failure condition and side effect. No sentence is padding; even 'Free' carries cost information an agent may need.

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 rich annotations and a fully described single-parameter schema, the remaining burden on the description is behavioral, and it covers the error case, side effects, and cost. The only gap is the post-call state of the row (deleted vs. marked cancelled), which is minor for a cancel operation with no output schema.

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?

Only one parameter (postId) exists and schema description coverage is 100%, so the schema already documents it as a social post UUID. The description adds no format, sourcing, or lookup guidance beyond that, making the baseline 3 correct.

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 description states a specific verb (cancel/remove) and resource (social post) and enumerates the exact post states it handles: scheduled, draft, failed, cancelled. That state enumeration, plus the publishing exclusion, lets an agent distinguish it from siblings like retry_social_post or get_social_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?

It clearly states when the tool applies (scheduled/draft/failed/cancelled posts) and when it does not (posts already 'publishing' return 409). It stops short of naming an alternative for the publishing case or routing failed posts to retry_social_post, so it is strong context without explicit alternative routing.

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