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

With no annotations, the description carries the full load and does well: it is clearly a non-mutating pre-check (not a submission), it discloses the return contents (per-document ok/missing/fail, blockers, score 0-100, fee, official sources), and it discloses the paid x402/$0.05 USDC-on-Base access model, which is essential for an agent to know before calling. It does not state data-retention or whether documents must actually be uploaded, which is why it falls short of 5.

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?

Four sentences, front-loaded with purpose, then usage, then return shape, then pricing. The pricing/value comparison sentence ('Agencies charge ~2,999 THB') is mildly promotional but does earn its place as a cost-justification cue for an agent deciding to spend USDC.

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 annotations and no output schema, so the description must supply everything — and it does describe return values and cost. For an 8-parameter tool the gaps are in the undocumented parameters and the absence of any note on what a 'fail' vs 'missing' distinction means in practice.

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 only 50%, and the description adds real meaning for the financial requirement ('500k THB') that contextualizes bank_balances_thb, plus mapping the tool to the DTV/METV enum. However, it says nothing about age, category, travel_date, passport_expiry or applying_from_thailand, and doesn't explain that 'documents' expects the enumerated doc keys.

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 ('Pre-check') and a specific resource ('Thailand DTV or METV application package') against a named authority checklist (MFA/embassy). It also names both supported visa types up front, so an agent knows exactly what is and isn't covered 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?

'Use when an agent helps a digital nomad, remote worker or tourist apply for a Thai visa' gives a clear triggering context. There are no sibling tools to route against, but no explicit when-not-to-use case (e.g. non-Thai visas, already-submitted applications) is stated.

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