list_accounts

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

The description includes a 'Read-only' label, which is a behavioral trait. However, with no annotations, it does not disclose authentication needs, response format, or whether the list is paginated. The description is adequate but lacks depth.

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 sentence that is direct and concise with no unnecessary words. It front-loads the key action and information.

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 the lack of output schema and annotations, the description covers the core functionality but leaves out details like response structure or potential limits. For a simple list tool, this is minimally complete.

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?

The tool has 0 parameters, and the schema coverage is 100%. The description adds no parameter information, which is acceptable as there are none. Baseline score of 4 applies.

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 verb 'list' and the resource 'Mercury bank accounts,' specifying the data returned (balances, account/routing numbers, status). This distinguishes it from sibling tools like 'get_account' (single account) and 'list_transactions' (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 provides no guidance on when to use this tool versus alternatives such as 'get_account' for a single account. There is no mention of prerequisites, limitations, or context where it is appropriate.

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