Transactions — Get

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

Annotations already establish read-only/non-destructive, so the bar is lower, yet the description still adds real domain context: split transactions return subtransactions, transfer_account_id flags transfers, and amounts are in milliunits. It doesn't cover not-found/error behavior, which would be the remaining useful addition.

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?

Four short, front-loaded sentences with the read marker first and zero filler. Each sentence contributes distinct information an agent needs.

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?

With an output schema present, return-value documentation is unnecessary, and the description covers the notable edge cases (splits, transfers, units). The gap is the undocumented plan_id, but otherwise complete for a simple getter.

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 must compensate, but it only indirectly gestures at transaction_id ('by ID') and says nothing at all about plan_id — its meaning, default, or whether it is required. The milliunits note describes values in the response, not the parameters.

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?

States a specific verb ('Get') and resource ('a single transaction by ID'), and the phrase 'single transaction' cleanly distinguishes it from the many transactions_list* siblings. An agent can pick this over transactions_list without opening any schema.

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 'by ID' framing clearly implies this is the tool to use when a transaction_id is already known, versus list/search tools for discovery. It never explicitly names alternatives or states when-not-to-use, so it stops short of a 5.

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