Compute Account Balances by Dimension

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

Annotations already indicate the tool is read-only, idempotent, and not destructive. The description adds behavioral details about including opening balances and outputting one row per dimension plus a total, which goes beyond what annotations 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?

Two sentences that are concise and front-loaded with the main action. Every sentence adds useful information without extraneous text.

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?

The tool has moderate complexity (4 params, no output schema) but strong annotations. The description explains the output structure and relation to sibling. It lacks edge-case or error-handling info, but for a read-only compute tool this is sufficient.

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 descriptions for all parameters. The description does not add parameter-specific details beyond the schema, but it provides context about the tool's operation (e.g., breakdown, total). Baseline 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: breaking down an account's balance per dimension with examples (e.g., bank sub-accounts). It distinguishes itself from the sibling tool 'compute_account_balance' by noting that the total row equals that tool's output.

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 when to use this tool (for a dimensional breakdown) versus the sibling for a total. It provides context on the output including opening balances, but does not explicitly state when not to use it or list alternatives beyond the one sibling.

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