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

Annotations indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=false. The description goes beyond annotations by explaining the side effect: recategorizing creates Category Rules for future similar transactions. This adds valuable behavioral context that annotations alone do not provide.

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 description is moderately long but well-structured: it starts with the core purpose, then explains the input format, then the behavioral side effect, and finally the return shape. Every sentence adds value, though it could be slightly more compact.

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?

Given that the tool has one parameter (an array), no output schema, and the description explains the return shape (`{ updated, results, errors }`), it is complete. It also differentiates from sibling tools and covers error handling for batches.

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 0%, so the description fully compensates by explaining that `items` is an array of objects with `transaction_id` and `category_id`, and specifies where to obtain these IDs from sibling tools. This adds essential meaning beyond the bare 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 clearly states the action ('Corrects the category of one or more transactions') and identifies the resource (transactions). It distinguishes from sibling tools like openfinance_list_transactions and openfinance_list_categories by indicating it is a write operation that modifies categorization.

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 when to use the tool ('fix miscategorized transactions and improve categorization accuracy going forward') and provides context for inputs (transaction_id from openfinance_list_transactions, category_id from openfinance_list_categories). It does not explicitly state when not to use it, but the guidance is clear and practical.

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