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

Annotations already declare destructiveHint: true, so the destructive nature is known. The description adds the eligibility constraint (draft/failed only), which is behavioral context beyond the annotation. It also reinforces permanence with 'permanently remove,' adding a nuance not present in the 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?

Two short sentences with zero redundancy. The action and constraint are front-loaded, and every word serves a purpose. It is efficient and easy to parse.

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 simple delete operation with one parameter, annotations cover destructiveness, an output schema exists, and the description provides the essential eligibility rule and usage trigger. Nothing needed for correct invocation is missing.

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 100% and the postId parameter is already described as 'The post ID to delete.' The tool description adds no additional semantic detail beyond that, 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?

The description states a specific verb ('delete') and resource ('post'), identifies the identifier (postId), and clarifies the scope by limiting eligible posts to draft and failed ones. This clearly distinguishes it from sibling tools like publish_post or update_post.

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 explicitly says 'Use this when the user wants to permanently remove a post,' which provides a direct usage condition. It also adds an eligibility constraint ('Only draft and failed posts can be deleted'), implicitly excluding published posts. However, it does not name alternative tools explicitly, so the guidance is clear but not exhaustive.

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