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

The description discloses the key behavioral constraint: the submitted ID list must be a complete permutation of existing block IDs. This goes beyond the annotations (which only say readOnly=false) and is consistent with the schema. It does not describe failure modes, authorization, or side effects, but with annotation support this is adequate.

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, with the purpose stated first and the constraint second. No redundant or filler content. Excellent structure.

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 tool is simple (two required params, no nesting) and has an output schema, so the description need not cover return values. It covers the essential operational constraint (complete permutation) and is sufficiently complete for selecting and invoking the tool.

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%, with both parameters (postId and orderedBlockIds) already described in the schema. The description restates the constraint on orderedBlockIds ('must contain every existing block id exactly once') but adds no additional meaning beyond the schema.

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 uses a specific verb ('Reorder') and resource ('blocks'), clearly distinguishing it from sibling tools like append_post_block, remove_post_block, and replace_post_block. The phrase 'by passing block IDs in the desired order' states the mechanism unambiguously.

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 provides clear context: it requires the full set of existing block IDs exactly once, implying a full reorder rather than a partial move. However, it does not explicitly name alternatives or exclude other block-manipulation tools, so it stops short of full usage guidance.

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