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

With no annotations, the description carries the full behavioral burden and does disclose the returned rate components: lodging, local and proportional meals, incidentals, and maximum per diem per season. It does not mention pagination behavior, the verification_url option, or explicitly state that the operation is read-only, leaving some behavioral context to the schema or inference.

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 front-loaded with the core purpose and return contents, then moves efficiently into filter and date/year semantics. It is appropriately sized, with only minor redundancy between the opening 'Get perdiem OCONUS' and the following expansion.

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?

Because there is no output schema, the description usefully explains the return values, including lodging, meal rates, incidentals, and maximum per diem. It is complete enough for the main call pattern, though it omits pagination and verification_url details that would make it fully self-contained for all seven parameters.

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 description adds useful meaning for the required OCONUS ISO code and for the q, date, and year filters, including the fiscal-year boundary. However, with schema description coverage at 71%, it does not compensate for undocumented parameters such as limit and offset, and it only lightly overlaps with the already-described verification_url.

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 verb and resource: get DoD per diem outside the continental U.S., covering foreign countries and selected U.S. territories. It distinguishes itself from CONUS per diem by explicitly saying 'outside the continental U.S.', but it does not name the closest sibling tools such as get_dtmo_perdiem_conus or search_dtmo_perdiem.

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?

Usage is implied by the OCONUS scope and by the notes that 'date' selects rates in force on that day and 'year' selects a fiscal year, with both omitted for the current fiscal year. However, there is no explicit guidance on when to choose this tool over sibling tools like search_dtmo_perdiem or get_dtmo_perdiem_conus.

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