Transactions: get transaction by id_by_customer

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

The description reinforces the READ-ONLY nature already declared in annotations, stating '🟢 READ-ONLY — Fetches data. Makes no changes.' No contradictions with annotations.

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 concise, but includes some redundancy (e.g., repeating the tool title in bold). It front-loads the READ-ONLY indicator and effectively uses two short paragraphs.

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 read tool with one optional parameter and no output schema, the description adequately explains the return: 'The response includes an array of transaction data.' However, it could clarify what 'id_by_customer' represents.

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 a single parameter 'api_key' already well-described in the schema. The description adds no additional parameter insight beyond the schema, so baseline score of 3 is appropriate.

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 tool's purpose: 'Get a single transaction for a specified customer account by id_by_customer.' It distinguishes from the sibling 'transactions_get' which retrieves all transactions.

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 advises obtaining the 'id_by_customer' via another endpoint first: 'You can get the "id_by_customer" by using the "/transactions/get method".' This provides a prerequisite, though it doesn't explicitly cover when not to use the tool.

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