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

Annotations already declare readOnly, idempotent, and non-destructive behavior, so the description only needs to add context beyond that. It adds the data source and unit, but does not disclose other operational traits such as default time range, ordering, or whether results are latest-only.

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 two short sentences with the key resource and scope front-loaded and the unit clarification placed immediately. No filler or redundant phrasing is present.

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 one-optional-parameter read-only tool, the description provides the data source, the specific account, and the unit of measurement. It does not document the response shape or date-range behavior, but the daily-series implication and available annotations make the tool callable without major gaps.

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 sole parameter 'limit' is already fully documented in the schema as 'Max rows to return,' giving 100% schema description coverage. The description adds no extra meaning about default behavior or maximum allowed values, so the baseline of 3 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 identifies the resource as the US Treasury's daily operating cash balance (Treasury General Account) and scopes it to data from the Daily Treasury Statement with values in millions of dollars. It is distinguishable from treasury_debt, treasury_auctions, and treasury_interest_rates, though it lacks an explicit action verb such as 'list' or 'get.'

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 does not state when to use this tool versus treasury_debt, treasury_auctions, treasury_exchange_rates, or treasury_interest_rates, nor does it describe exclusions or alternatives. The intended use must be inferred entirely from the resource name and noun-phrase description.

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