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

Annotations cover the safety profile (readOnly, idempotent, openWorld, non-destructive), and the description adds substantial context beyond them: keyless auth, a hard 92-day window cap, and the important caveat that payments to private individuals arrive with the code masked by the Treasury. It also states what aggregation is returned (totals and top counterparties across the whole window, not just the returned rows), which prevents misreading the result.

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?

Front-loaded with source, scope and window before the field enumeration, and the sibling routing is placed last where it belongs. The row-field list is somewhat dense, but with no output schema it earns its place by explaining the return shape.

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?

No output schema exists, yet the description fully describes the return: per-row fields, totals and top counterparties, and the newest `limit` rows. Combined with annotations and a fully documented schema, an agent has everything needed to call it correctly.

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 description coverage is 100%, so the schema already documents all six parameters with examples (e.g. EDRPOU codes, comma-separation, defaults). The description adds only the 92-day window constraint, which the schema's date_from description already states, so 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?

States a specific verb+resource+source: treasury payments from spending.gov.ua, made by and/or to an EDRPOU within a date window. It enumerates the row shape (date, amount, payer, recipient, purpose, budget code, KEKV, contract) and names the sibling tools it is not (ua_spend_between, ua_spend_prozorro_link), so an agent can distinguish it without opening any 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?

Provides an explicit 'Use for:' list of concrete scenarios (who a city council or ministry paid, which public bodies paid a supplier, and what for) plus two named alternatives with the condition that selects each. No inference required.

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