recategorize_transaction

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

Annotations provide readOnlyHint=false and idempotentHint=true, so the description doesn't need to restate those. The description adds no extra behavioral context beyond the annotations, such as whether the change is reversible, whether it affects budget calculations, or whether it requires specific permissions. With annotations covering the basic safety profile, a 3 is appropriate.

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 a single, efficient sentence with no wasted words. It front-loads the action and resource clearly, making it easy for an agent to parse quickly.

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 two-parameter mutation tool with full schema coverage and annotations, the description is mostly adequate. However, it lacks guidance on how to determine valid category values (e.g., whether category accepts a name or ID, and how to resolve ambiguity), which could be important for correct invocation. The absence of an output schema is not a major issue given the simplicity.

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 100%, so the schema already documents both parameters (transaction_id and category). The description adds no additional meaning beyond what the schema provides, such as the format of category (name vs ID) or how to find valid categories. Baseline 3 is correct when the schema does the heavy lifting.

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 'Change the category of an existing transaction' clearly states the verb (change) and resource (category of an existing transaction), distinguishing it from sibling tools like create_transaction or update_transaction. It is concise and unambiguous, though it doesn't explicitly name a sibling alternative.

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 implies usage context: it is for modifying an existing transaction's category, not for creating or deleting transactions. However, it does not explicitly state when to use this tool versus update_transaction or other category-related tools, nor does it mention any prerequisites like the transaction existing or category validity.

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