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

Annotations provide basic safety hints (readOnlyHint=false, destructiveHint=false). The description adds the constraint that the ID list must include every existing block exactly once. However, it does not mention side effects like immediate persistence or whether the operation is reversible.

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 sentences, no redundant information, and front-loaded with the main action. Every word serves a purpose.

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?

The description covers the essential input constraints. Since an output schema exists, the lack of return value explanation is acceptable. However, some additional context about immediate effect or prerequisites would improve completeness.

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%, so both parameters are documented. The description restates the constraint from the schema ('must match the existing set exactly') without adding new meaning beyond what the schema already provides.

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 clearly states the action 'reorder blocks' and the resource 'post blocks', specifying that the ID list must contain every existing block exactly once, distinguishing it from sibling tools like remove_post_block and replace_post_block.

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?

The description explains what the tool does but does not explicitly state when to use it versus alternatives or when not to use it. It implicitly distinguishes from siblings but lacks direct guidance.

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