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

With no annotations, the description carries the full burden. It usefully discloses that CONUS returns five standard M&IE tiers, that oconus returns the generic total table, and that omitting date defaults to today. It does not mention whether this is purely read-only, how errors behave, or what the response shape looks like, so transparency is adequate but incomplete.

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 short and front-loaded with the core behavior. The leading 'M&IE meal breakdowns' is somewhat redundant with the tool name, but the remaining sentences are efficient and informative.

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?

There is no output schema, so the description must explain return content; it does so by naming the breakfast/lunch/dinner/incidental breakdown, the five CONUS tiers, and the oconus generic table. Defaults for date and region are also covered. Minor gaps remain around parameter 'total' and verification_url behavior, but the core lookup is 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?

Schema coverage is 100%, so the schema already documents all four parameters. The description adds meaning for region and date defaults, but does not explain the total or verification_url parameters beyond what the schema already provides. This meets the baseline for high schema coverage.

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 a specific resource and output: daily M&IE totals broken into breakfast, lunch, dinner and incidental expenses. It doesn't explicitly differentiate itself from close siblings like get_dtmo_perdiem_conus or get_dtmo_perdiem_oconus, but its purpose is still understandable without opening the 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 description gives useful parameter-selection guidance: CONUS is returned by default, and region=oconus selects the generic DTMO/DSSR table. However, it doesn't say when to use this tool instead of siblings such as get_dtmo_perdiem_conus or get_dtmo_perdiem_oconus, leaving usage implicit.

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