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

Annotations mark this non-read-only and non-idempotent, and the description supplies the missing reason: a $0.01 per-call charge in USDC on Solana via x402, settled only on retry with a payment payload. This is exactly the kind of hidden cost/side-effect context annotations alone cannot convey. It stops at 4 because failure modes and what happens if payment validation fails are not covered.

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 the purpose, then cost, then the payment mechanics — a sensible order. Three dense sentences with no filler, though the parenthetical payment instructions and HTTP endpoint are tightly packed and the HTTP URL is of limited use to an MCP caller.

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?

The commercial mechanics are complete, but with no output schema the description carries the burden of describing what a 'ranked lawful route' actually contains (route fields, licence verdict shape, ranking rationale) and it only gestures at this. An agent knows how to call it and what it costs, but not what it will receive.

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 0% and the single parameter 'need' is undocumented in the schema. The description only offers 'state a need', which hints at natural language but gives no format, length, example, or specificity guidance. For a 1-param tool with zero coverage, this is a real gap the description was positioned to fill.

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 and resource — 'state a need, get ranked lawful routes with licence verdicts' — which is clearly a routing/lookup service, distinct from siblings like atlas_record and atlas_changes. The phrase 'lawful routes' is somewhat opaque (routes of what, ranked by what criteria), so it stops short of a 5, but an agent can tell what class of operation this is.

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?

There is no explicit when-to-use vs when-not, and no mention of the atlas_* siblings, so alternative selection is left to inference. That said, the invocation path is unusually well spelled out — the two-step x402 challenge/retry flow and the HTTP equivalent endpoint — which is genuine procedural usage guidance even if the 'when' is missing.

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