compare_countries

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

Annotations already cover the safety profile (readOnlyHint true, openWorldHint false), but the description adds rich behavioral context: what gets computed (fees, funding, spread, withdrawals, fiat rails), how live modes fall back to bundled baselines on failure, and that live overrides are resolved once over the union of venues across selected countries.

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 very long and dense, packing many clauses and parenthetical lists into a few sentences. It is front-loaded with usage triggers, but several details (e.g., enumerated output components, fallback behavior) could be trimmed or structured more cleanly for an agent.

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 complex tool with 19 parameters, multiple modes, and no output schema, the description is unusually complete. It explains defaults, persona selection, country limits, live vs bundled modes, fallback behavior, and the kinds of results returned (per-country winner, cost gaps, availability matrix, narrative advice), leaving nothing critical for correct invocation.

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 19 parameters in detail. The description restates some defaults (persona, countries) and mentions overrides, but adds little semantic detail beyond what the schema provides, so the 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 states a specific verb and resource: 'run ONE trader persona/profile through the FULL annual all-in stack ... across SEVERAL countries in a single call'. It clearly distinguishes this multi-country comparison from sibling tools like compare_total_cost or compare_exchange_fees by emphasizing cross-country residency effects and per-country winners.

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?

It gives explicit user intents ('同样的交易习惯在哪个国家最便宜/我要搬家或换居住地...'), defaults (active_spot_trader, 7 countries), and parameter overrides. However, it does not name alternative tools or state when not to use this tool, so it stops just short of a 5.

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